Circuit board and display module

Abstract

The invention provides a circuit board and a display module. The circuit board comprises a substrate, and a plurality of voltage conversion units and a plurality of light-emitting driving units which are arranged on the substrate, and each voltage conversion unit comprises an input end and an output end and is configured to output a preset voltage; the light-emitting driving unit is connected to the output end of the voltage conversion unit and is configured to drive the light-emitting unit; wherein the plurality of voltage conversion units and the plurality of driving units are arranged in a one-to-one correspondence manner, and the voltage conversion units are arranged between the adjacent light-emitting driving units; the voltage conversion unit comprises a first inductor and a second inductor which are connected in parallel and are arranged in a staggered mode. According to the circuit board provided by the invention, the voltage conversion units are arranged between the adjacent light-emitting driving units, and the first inductors and the second inductors in the voltage conversion units are arranged in the staggered manner, so that components with relatively high heat can be arranged in a dispersed manner, and the heating addition influence between the components is improved.

Description

Technical Field

[0001] At least one embodiment of the present disclosure relates to a circuit board and a display module. Background Art

[0002] With the development of Light Emitting Diode (LED) technology, its application scope has been continuously expanding. In some liquid crystal screen devices, a constant current board can output a constant current to an LED backlight source, thereby ensuring the consistency of the brightness and chromaticity of each LED. Summary of the Invention

[0003] At least one embodiment of the present disclosure provides a circuit board, including: a substrate; a plurality of voltage conversion units and a plurality of light emitting driving units disposed on the substrate, the voltage conversion unit including an input end and an output end and being configured to output a preset voltage; the light emitting driving unit being connected to the output end of the voltage conversion unit and being configured to drive a light emitting unit; wherein, the plurality of voltage conversion units and the plurality of light emitting driving units are arranged in one-to-one correspondence, and a voltage conversion unit is disposed between adjacent light emitting driving units; the voltage conversion unit includes a first inductor and a second inductor connected in parallel, and the first inductor and the second inductor are arranged in a staggered manner.

[0004] For example, according to an embodiment of the present disclosure, the circuit board includes a first edge close to the voltage conversion unit in a first direction, the first direction being a direction from the voltage conversion unit to the light emitting driving unit; a first distance between the first inductor and the first edge in the first direction is a first distance, a second distance between the second inductor and the first edge in the first direction is a second distance, and the first distance is different from the second distance.

[0005] For example, according to an embodiment of the present disclosure, a difference between the first distance and the second distance is less than or equal to 1 / 2 of a width dimension of the first inductor in the first direction.

[0006] For example, according to an embodiment of the present disclosure, the plurality of voltage conversion units include a first voltage conversion unit and a second voltage conversion unit located on both sides of a first light-emitting driving unit in a first direction, where the first direction is the direction from the voltage conversion unit to the light-emitting driving unit; the first voltage conversion unit includes a first inductance module, and the second voltage conversion unit includes a second inductance module; the interval between the first inductance module and the second inductance module in the first direction is y, there is a non-overlapping part between the positive projection of the first inductance on a first reference plane and the positive projection of the second inductance on the first reference plane, the size of the non-overlapping part in the first direction is h, and the size of the light-emitting driving unit in the first direction is x, then: y = a × x + b × h, 2 < a < 4, 1 < b < 3; where the second direction intersects the first direction, and the first reference plane is a plane perpendicular to the second direction.

[0007] For example, according to an embodiment of the present disclosure, the plurality of voltage conversion units include a first voltage conversion unit and a second voltage conversion unit located on both sides of a first light-emitting driving unit. The first voltage conversion unit includes a first inductance module, a first capacitance module, and a first switching module, and the second voltage conversion unit includes a second inductance module; the interval between the first inductance module and the second inductance module in a first direction is y, the size of the first inductance module in the first direction is y1, the size of the first capacitance module in the first direction is y2, and the size of the first switching module in the first direction is y3, then: y = k × y1 + y3 + 2 × y2, 1 < k < 3; where the first direction is the direction from the voltage conversion unit to the light-emitting driving unit.

[0008] For example, according to an embodiment of the present disclosure, the plurality of voltage conversion units include a first voltage conversion unit and a second voltage conversion unit located on both sides of the first light-emitting driving unit. The first voltage conversion unit includes a first inductor module, a first capacitor module, and a first switch module. The first inductor module includes the first inductor and the second inductor connected in parallel with each other. The first inductor and the second inductor have a first interval in a second direction. The first capacitor module includes a first output capacitor module and a first input capacitor module connected in parallel with each other. The first output capacitor module and the first input capacitor module have a second interval in the second direction. The first switch module includes a first switch and a second switch connected in parallel with each other. The first switch and the second switch have a third interval in the second direction. The second voltage conversion unit includes a second capacitor module. The second capacitor module includes a second output capacitor module and a second input capacitor module connected in parallel with each other. The second output capacitor module and the second input capacitor module have a fourth interval in the second direction. At least one of the fourth interval and the first interval, the second interval, and the third interval has an overlapping portion on a second reference plane. The second reference plane is a plane perpendicular to a first direction. The first direction is a direction pointing from the voltage conversion unit to the light-emitting driving unit. The second direction is parallel to the substrate and intersects with the first direction.

[0009] For example, according to an embodiment of the present disclosure, the first interval, the second interval, the third interval, and the fourth interval have a common overlapping portion on the second reference plane.

[0010] For example, according to an embodiment of the present disclosure, a dimension of the common overlapping portion in the second direction is less than or equal to a dimension of the first interval in the second direction.

[0011] For example, according to an embodiment of the present disclosure, a ratio of the dimension of the common overlapping portion in the second direction to the dimension of the first interval in the second direction is 0.3 to 0.7.

[0012] For example, according to an embodiment of the present disclosure, the first interval, the second interval, the third interval, and the fourth interval are configured to satisfy at least one of the following conditions: the first interval is greater than or equal to 10 mm; the second interval is greater than or equal to 28 mm; the third interval is greater than or equal to 8 mm; the fourth interval is greater than or equal to 4 mm.

[0013] For example, according to an embodiment of the present disclosure, the second voltage conversion unit includes a second inductor module, and the second inductor module includes a third inductor and a fourth inductor that are oppositely arranged in a second direction; the second direction is parallel to the substrate and intersects the first direction; the first interval is configured to satisfy at least one of the following conditions: a first overlapping portion exists between the positive projection of the first interval on the second reference plane and the positive projection of the third inductor or the fourth inductor on the second reference plane; the dimension of the first overlapping portion in the second direction is greater than 1 / 3 of the dimension of the third inductor or the fourth inductor in the second direction; a third overlapping portion exists between the positive projection of the first interval on the second reference plane and the positive projection of the second input capacitor module on the second reference plane, and the dimension of the third overlapping portion in the second direction is greater than 1 / 3 of the dimension of the second input capacitor module in the second direction.

[0014] For example, according to an embodiment of the present disclosure, the dimension of the first interval in the second direction is the same as the spacing between the third inductor and the fourth inductor in the second direction.

[0015] For example, according to an embodiment of the present disclosure, the second interval is configured to satisfy at least one of the following conditions: the second voltage conversion unit includes a second inductor module, and at least partial overlap exists between the positive projection of the second interval on the second reference plane and the positive projection of the second inductor module on the second reference plane; an eighth overlapping portion exists between the positive projection of the second interval on the second reference plane and the positive projection of the second output capacitor module or the second input capacitor module on the second reference plane, and the dimension of the eighth overlapping portion in the second direction is greater than 2 / 3 of the dimension of the second output capacitor module or the second input capacitor module in the second direction.

[0016] For example, according to an embodiment of the present disclosure, the second voltage conversion unit includes a second inductor module, and the second inductor module includes a third inductor and a fourth inductor that are oppositely arranged in the second direction; the second interval is configured to satisfy at least one of the following conditions: the dimension of the second interval in the second direction is greater than the dimension of the first inductor or the second inductor in the second direction; a sixth overlapping portion exists between the positive projection of the second interval on the second reference plane and the positive projection of the first inductor or the second inductor on the second reference plane, and the dimension of the sixth overlapping portion in the second direction is greater than 1 / 3 of the dimension of the first inductor in the second direction; at least partial overlap exists between the positive projection of the second interval on the second reference plane and the positive projection of the third inductor on the second reference plane; complete overlap exists between the positive projection of the second interval on the second reference plane and the positive projection of the fourth inductor on the second reference plane.

[0017] For example, according to an embodiment of the present disclosure, the second voltage conversion unit includes a second inductor module, and the second inductor module includes a third inductor and a fourth inductor that are oppositely arranged in the second direction; the third interval is configured to satisfy at least one of the following conditions: a fourteenth overlapping portion exists between the positive projection of the third interval on the second reference plane and the positive projection of the third inductor or the fourth inductor on the second reference plane; a sixteenth overlapping portion exists between the positive projection of the third interval on the second reference plane and the positive projection of the second output capacitor module or the second input capacitor module on the second reference plane.

[0018] For example, according to an embodiment of the present disclosure, the size of the fourteenth overlapping portion in the second direction is greater than 1 / 2 of the size of the third inductor in the second direction; and / or, the size of the sixteenth overlapping portion in the second direction is greater than 1 / 3 of the size of the second output capacitor module or the second input capacitor module in the second direction.

[0019] For example, according to an embodiment of the present disclosure, the second voltage conversion unit includes a second inductor module; there is a non-overlapping portion between the positive projection of the first inductor module on the second reference plane and the positive projection of the second inductor module on the second reference plane.

[0020] For example, according to an embodiment of the present disclosure, the voltage conversion unit includes an inductor module, a diode module, a switch module, an output capacitor module, and an input capacitor module; the inductor module includes the first inductor and the second inductor; the inductor module is connected between the input end of the voltage conversion unit and the positive electrode of the diode module; the negative electrode of the diode module is connected to the output end of the voltage conversion unit; the switch module includes a control end, an input end, and an output end, and the control end of the switch module is configured to receive a control signal for controlling conduction or cut-off between the input end and the output end of the switch module. One of the input end and the output end of the switch module is connected between the inductor module and the diode module, and the other of the input end and the output end of the switch module is connected to the ground terminal; the first pole of the output capacitor module is connected to the negative electrode of the diode module, and the second pole of the output capacitor module is connected to the ground terminal; the input capacitor module is connected between the input end and the ground terminal.

[0021] For example, according to an embodiment of the present disclosure, the substrate includes a first edge and a second edge disposed opposite to each other in the first direction. In each of the driving structures, the first direction is the direction from the voltage conversion unit to the light-emitting driving unit. At least in the voltage conversion unit closest to the first edge of the substrate, the inductance module is disposed on a side of the voltage conversion unit away from the light-emitting driving unit in the first direction; the output capacitance module is disposed on a side of the voltage conversion unit close to the light-emitting driving unit in the first direction; the input capacitance module and the output capacitance module are disposed opposite to each other in a second direction, and the second direction is parallel to the substrate and intersects with the first direction; the diode module is closer to a third edge of the substrate than the inductance module and the output capacitance module, and the third edge connects the first edge and the second edge; the switching module is disposed between the inductance module and the output capacitance module.

[0022] For example, according to an embodiment of the present disclosure, the circuit board is configured to satisfy at least one of the following conditions: the switching module includes at least a first switching element and a second switching element connected in parallel; the distance between the first switching element and the second switching element in the second direction is greater than or equal to 8 mm; the output capacitance module includes at least a first output capacitance module and a second output capacitance module connected in parallel; the distance between the first output capacitance module and the second output capacitance module in the first direction is greater than or equal to 2 mm; in the voltage conversion unit closest to the first edge of the substrate, the distance between the inductance module and the outer periphery of the substrate in the first direction is greater than or equal to 5 mm; the diode module includes a first diode and a second diode connected in parallel, and the distance between the first diode and the second diode in the first direction is greater than or equal to 9 mm; wherein, the first direction is the direction from the voltage conversion unit to the light-emitting driving unit, and the second direction is parallel to the substrate and intersects with the first direction.

[0023] For example, according to an embodiment of the present disclosure, the voltage conversion unit is configured to satisfy at least one of the following conditions: the distance between the inductance module and the switch module in the first direction is greater than or equal to 10 millimeters; the distance between the inductance module and the diode module in the second direction is greater than or equal to 12 millimeters; the distance between the inductance module and the output capacitance module in the first direction is greater than or equal to 15 millimeters; the distance between the inductance module and the input capacitance module in the first direction is greater than or equal to 29 millimeters; the distance between the diode module and the switch module in the second direction is greater than or equal to 10 millimeters; the distance between the diode module and the output capacitance module in the first direction is greater than or equal to 4 millimeters; the distance between the switch module and the output capacitance module in the second direction is greater than or equal to 3 millimeters; the distance between the switch module and the input capacitance module in the first direction is greater than or equal to 6 millimeters; the distance between the switch module and the input capacitance module in the second direction is greater than or equal to 2 millimeters.

[0024] For example, according to an embodiment of the present disclosure, the diode module includes a Schottky diode; and / or, the switch module includes a transistor.

[0025] For example, according to an embodiment of the present disclosure, a plurality of voltage conversion units are provided, and a plurality of light-emitting driving units are provided; the plurality of voltage conversion units and the plurality of light-emitting driving units are arranged in one-to-one correspondence, and the corresponding voltage conversion unit and the light-emitting driving unit are connected to form a plurality of driving structures; the plurality of driving structures are arranged in sequence along a first direction, and the plurality of light-emitting driving units and the plurality of voltage conversion units are alternately arranged along the first direction; the plurality of driving structures include a first driving structure and a second driving structure, the first driving structure includes a first voltage conversion unit and a first light-emitting driving unit, and the second driving structure includes a second voltage conversion unit and a second light-emitting driving unit; the first driving structure and the second driving structure are configured to satisfy at least one of the following conditions: there is a non-overlapping portion between the orthographic projection of the first voltage conversion unit on a second reference plane and the orthographic projection of the second voltage conversion unit on a plane perpendicular to the first direction; the second reference plane is a plane perpendicular to the first direction; there is a non-overlapping portion between the orthographic projection of the first light-emitting driving unit on the second reference plane and the orthographic projection of the second light-emitting driving unit on the second reference plane; there is a non-overlapping portion between the orthographic projection of the first voltage conversion unit on the second reference plane and the orthographic projection of the first light-emitting driving unit on the second reference plane; there is a non-overlapping portion between the orthographic projection of the first voltage conversion unit on the second reference plane and the orthographic projection of the second light-emitting driving unit on the second reference plane; there is a non-overlapping portion between the orthographic projection of the second voltage conversion unit on the second reference plane and the orthographic projection of the second light-emitting driving unit on the second reference plane; there is a non-overlapping portion between the orthographic projection of the second voltage conversion unit on the second reference plane and the orthographic projection of the first light-emitting driving unit on the second reference plane.

[0026] For example, according to an embodiment of the present disclosure, the first voltage conversion unit includes a first diode module and a first input capacitor module, and the first light-emitting driving unit includes a first switching tube module and a first driving module; the second voltage conversion unit includes a second output capacitor module and a second inductor module, and the second light-emitting driving unit includes a second switching tube module and a second driving module; the first driving structure and the second driving structure are configured to satisfy at least one of the following conditions: a first non-overlapping portion exists between the orthographic projection of the first diode module on the second reference plane and the orthographic projection of the second output capacitor module on the second reference plane; a second non-overlapping portion exists between the orthographic projection of the first input capacitor module on the second reference plane and the orthographic projection of the second inductor module on the second reference plane; a third non-overlapping portion exists between the orthographic projection of the first switching tube module on the second reference plane and the orthographic projection of the second switching tube module on the second reference plane; a fourth non-overlapping portion exists between the orthographic projection of the first driving module on the second reference plane and the orthographic projection of the second driving module on the second reference plane; a fifth non-overlapping portion exists between the orthographic projection of the first diode module on the second reference plane and the orthographic projection of the first switching tube module on the second reference plane; a sixth non-overlapping portion exists between the orthographic projection of the first input capacitor module on the second reference plane and the orthographic projection of the first driving module on the second reference plane; a seventh non-overlapping portion exists between the orthographic projection of the first diode module on the second reference plane and the orthographic projection of the second switching tube module on the second reference plane; an eighth non-overlapping portion exists between the orthographic projection of the first input capacitor module on the second reference plane and the orthographic projection of the second driving module on the second reference plane; a ninth non-overlapping portion exists between the orthographic projection of the first switching tube module on the second reference plane and the orthographic projection of the second output capacitor module on the second reference plane; a tenth non-overlapping portion exists between the orthographic projection of the first driving module on the second reference plane and the orthographic projection of the second inductor module on the second reference plane; an eleventh non-overlapping portion exists between the orthographic projection of the second output capacitor module on the second reference plane and the orthographic projection of the second switching tube module on the second reference plane; a twelfth non-overlapping portion exists between the orthographic projection of the second inductor module on the second reference plane and the orthographic projection of the second driving module on the second reference plane.

[0027] For example, according to an embodiment of the present disclosure, the substrate includes a first conductive layer and a first solder mask layer. The first conductive layer and the first solder mask layer are located on a side of the substrate where the light-emitting driving unit is provided. The first conductive layer is located on a side of the first solder mask layer away from the light-emitting driving unit; the voltage conversion unit includes an inductor module, a diode module, and a switch module. The inductor module includes the first inductor and the second inductor; a first opening exposing the first conductive layer is formed in the first solder mask layer; the first opening surrounds at least one of the inductor module, the diode module, and the switch module.

[0028] For example, according to an embodiment of the present disclosure, the first opening includes a first opening portion, a second opening portion, and a third opening portion that do not overlap each other; the first opening portion is located between the inductor module, the diode module, and the switch module, the second opening portion surrounds the inductor module, and the third opening portion surrounds the diode module; wherein, the area of the first opening portion is larger than the area of the second opening portion, and the area of the first opening portion is larger than the area of the third opening portion.

[0029] For example, according to an embodiment of the present disclosure, the area of the first opening portion is less than or equal to 800 square millimeters; the area of the second opening portion is greater than or equal to 320 square millimeters; the area of the third opening portion is greater than or equal to 90 square millimeters.

[0030] For example, according to an embodiment of the present disclosure, the substrate includes a second conductive layer and a second solder mask layer located on a side of the first conductive layer away from the first solder mask layer. The second conductive layer is located between the second solder mask layer and the first conductive layer; a second opening exposing the second conductive layer is formed in the second solder mask layer; the orthographic projection of the second opening on a third reference plane overlaps with the orthographic projection of the first opening on the third reference plane; the third reference plane is parallel to the substrate.

[0031] For example, according to an embodiment of the present disclosure, it further includes: a plurality of vias that penetrate at least the first conductive layer and the second conductive layer. The plurality of vias are arranged in an array; the orthographic projection of the first opening on the third reference plane covers at least a part of the orthographic projection of the vias on the third reference plane.

[0032] For example, according to an embodiment of the present disclosure, it further includes a shielding component; the shielding component is at least provided on opposite sides of the light-emitting driving unit in a first direction. The first direction is a direction from the voltage conversion unit to the light-emitting driving unit.

[0033] At least one embodiment of the present disclosure provides a display module, including: a backplane; a circuit board as described in any of the above embodiments, disposed on the backplane; a light-emitting unit, disposed on a side of the backplane away from the circuit board and connected to the driving structure; and a housing, covering the outside of the circuit board; wherein the housing includes a top wall and a bottom wall oppositely disposed in a first direction; the first direction is a direction from the voltage conversion unit to the light-emitting driving unit; the housing is configured to satisfy at least one of the following conditions: a first through hole is formed in the top wall, and the first through hole communicates the internal space and the external space of the housing; and a second through hole is formed in the bottom wall, and the second through hole communicates the internal space and the external space of the housing.

[0034] For example, according to an embodiment of the present disclosure, the housing further includes a side wall connecting the top wall and the bottom wall, and a third through hole is formed in the side wall; a positive projection of the third through hole on a third reference plane overlaps a positive projection of the driving structure on the third reference plane; the third reference plane is parallel to the substrate. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, the accompanying drawings of the embodiments will be briefly introduced below. Obviously, the accompanying drawings in the following description only relate to some embodiments of the present disclosure and do not limit the present disclosure.

[0036] Figure 1 A schematic diagram of a lamp board exemplified by the present disclosure.

[0037] Figure 2 A schematic diagram of the area division of a light-emitting unit exemplified by the present disclosure.

[0038] Figure 3 A schematic diagram of the main board driving architecture of a light-emitting unit exemplified by the present disclosure.

[0039] Figure 4 A schematic diagram of the secondary board driving architecture of a light-emitting unit exemplified by the present disclosure.

[0040] Figure 5 Another schematic diagram of a lamp board exemplified by the present disclosure.

[0041] Figure 6 Another schematic diagram of the area division of a light-emitting unit exemplified by the present disclosure.

[0042] Figure 7 Another schematic diagram of the main board driving architecture of a light-emitting unit exemplified by the present disclosure.

[0043] Figure 8 Another schematic diagram of the secondary board driving architecture of a light-emitting unit exemplified by the present disclosure.

[0044] Figure 9 Schematic diagram of a light-emitting unit driving circuit provided by this disclosure.

[0045] Figure 10A Schematic diagram of a circuit board provided by this disclosure.

[0046] Figure 10B is Figure 10A Partial schematic diagram of the shown circuit board.

[0047] Figure 11 Schematic diagram of another light-emitting unit driving circuit provided by this disclosure.

[0048] Figure 12A Schematic diagram of another circuit board provided by this disclosure.

[0049] Figure 12B is Figure 12A Partial schematic diagram of the shown circuit board.

[0050] Figure 13A Schematic diagram of the light-emitting unit driving circuit provided by at least one embodiment of this disclosure.

[0051] Figure 13B Schematic diagram of the principle of the voltage conversion unit in the light-emitting unit driving circuit provided by an example of this disclosure.

[0052] Figure 13C Schematic diagram of the principle of the voltage conversion unit in the light-emitting unit driving circuit provided by another example of this disclosure.

[0053] Figure 13D Schematic diagram of the principle of the control module in the voltage conversion unit provided by an example of this disclosure.

[0054] Figure 13E Equivalent circuit schematic diagram of the control module provided by an example of this disclosure.

[0055] Figure 13F Schematic diagram of the principle of the control module in the voltage conversion unit provided by another example of this disclosure.

[0056] Figure 13G Equivalent circuit schematic diagram of the control module provided by another example of this disclosure.

[0057] Figure 14 Schematic diagram of another light-emitting unit driving circuit provided by this disclosure.

[0058] Figure 15A Schematic diagram of one side surface of the circuit board provided by at least one embodiment of this disclosure.

[0059] Figure 15B Schematic diagram of the other side surface of the circuit board provided by at least one embodiment of the present disclosure.

[0060] Figure 15C is Figure 15A Partial schematic diagram of the shown circuit board.

[0061] Figure 15D is Figure 15A Planar schematic diagram of the shown circuit board.

[0062] Figure 16 Schematic diagram of the light-emitting unit driving circuit provided by another example of the present disclosure.

[0063] Figure 17A Schematic diagram of the circuit board provided by still another example of the present disclosure.

[0064] Figure 17B is Figure 17A Partial schematic diagram of the shown circuit board.

[0065] Figure 17C is Figure 17A Planar schematic diagram of the shown circuit board.

[0066] Figure 18 Schematic diagram of the light-emitting unit driving circuit provided by still another example of the present disclosure.

[0067] Figure 19 Schematic diagram of the housing provided by an example of the present disclosure. Detailed implementation manners

[0068] To make the objectives, technical solutions, and advantages of the embodiments of the present disclosure clearer, the technical solutions of the embodiments of the present disclosure will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present disclosure. Obviously, the described embodiments are some, but not all, of the embodiments of the present disclosure. All other embodiments obtained by those of ordinary skill in the art based on the described embodiments of the present disclosure without creative efforts shall fall within the scope of protection of the present disclosure.

[0069] Unless otherwise defined, the technical terms or scientific terms used in the present disclosure shall have the ordinary meanings understood by those of ordinary skill in the art to which the present disclosure pertains. The "first", "second", and similar terms used in the present disclosure do not denote any order, quantity, or importance, but are only used to distinguish different components. The terms such as "including" or "comprising" mean that the elements or items appearing before this term cover the elements or items listed after this term and their equivalents, without excluding other elements or items.

[0070] In the embodiments of the present disclosure, features such as "vertical", "parallel", and "identical" include the strictly defined features of "vertical", "parallel", "identical", etc., as well as cases with certain errors such as "substantially vertical", "substantially parallel", "substantially identical", etc. Considering the measurement and errors associated with the measurement of a specific quantity (i.e., the limitations of the measurement system), it means within the acceptable deviation range for a specific value determined by those of ordinary skill in the art. The "center" in the embodiments of the present disclosure may include a position strictly located at the geometric center and a position of a substantially center within a small area around the geometric center. For example, "substantially" can mean within one or more standard deviations, or within 10% or 5% of the value.

[0071] Currently, local dimming technology (Local Dimming, LD) has been widely used in the splicing screen bands on the market, while most commercial display advertising screens do not have the function of local dimming, and the brightness is generally lower than 1000 nit. Most of such products use an alternating current to direct current (AC / DC) converter to convert the 220v alternating voltage into a voltage matching the LED strip to achieve constant current drive of the LED strip. At the same time, the components of the AC / DC converter support high-power output, and the requirements for the package size and height of the components are relatively low.

[0072] In order to achieve the local dimming function of a display device such as a commercial display advertising screen while meeting the requirements of backlight brightness and wide-temperature operation, voltage conversion needs to be carried out through a direct current to direct current (DC / DC) converter, and at the same time, constant current output is controlled. In addition, higher requirements are also put forward for the package size and height of the components. Limited by size, cost, etc., the DC / DC converter often uses power MOSFETs (metal-oxide-semiconductor field effect transistors) with a smaller package, and often cannot add a heat sink. This causes the MOSFET to face the problem of overheating. On this basis, the temperature rise of the components is often too high, and it is difficult to improve the heat dissipation efficiency.

[0073] For example, local dimming technology can divide the entire light-emitting unit into multiple separately drivable light-emitting zones, and each light-emitting zone includes one or more LEDs. The drive current of the LEDs in the light-emitting zones corresponding to these parts is automatically adjusted according to the gray levels to be displayed in different parts of the display screen, so as to achieve separate adjustment of the brightness of each zone in the light-emitting unit, thereby improving the contrast of the display screen. Local dimming technology is usually only applicable to direct-lit light-emitting units, and multiple LEDs serving as light sources are, for example, evenly distributed across the entire backplane.

[0074] At least one embodiment of the present disclosure further provides a circuit board, including: a substrate, and a plurality of voltage conversion units and a plurality of light-emitting driving units disposed on the substrate. The voltage conversion unit includes an input end and an output end, and is configured to output a preset voltage; the light-emitting driving unit is connected to the output end of the voltage conversion unit and is configured to drive a light-emitting unit; wherein, the plurality of voltage conversion units and the plurality of driving units are arranged in one-to-one correspondence, and a voltage conversion unit is disposed between adjacent light-emitting driving units; the voltage conversion unit includes a first inductor and a second inductor connected in parallel, and the first inductor and the second inductor are arranged in a staggered manner. In the circuit board provided by the present disclosure, by disposing a voltage conversion unit between adjacent light-emitting driving units and arranging the first inductor and the second inductor in the voltage conversion unit in a staggered manner, components with higher heat can be dispersed, and the heating additive effect between components can be improved.

[0075] At least one embodiment of the present disclosure further provides a display module, including: a backplane; the circuit board according to any one of the above embodiments, disposed on the backplane; a light-emitting unit, disposed on a side of the backplane away from the circuit board and connected to the driving structure; and a housing, covering the outside of the circuit board; wherein, the housing includes a top wall and a bottom wall oppositely disposed in a first direction; the first direction is a direction from the voltage conversion unit to the light-emitting driving unit; the housing is configured to satisfy at least one of the following conditions: a first through hole is formed in the top wall, and the first through hole communicates the internal space and the external space of the housing; a second through hole is formed in the bottom wall, and the second through hole communicates the internal space and the external space of the housing. In the display module provided by at least one embodiment of the present disclosure, the first through hole formed in the top wall and the second through hole formed in the bottom wall can communicate the internal and external spaces of the housing, can dissipate heat from both sides of the circuit board in the first direction respectively, accelerate the heat exchange between the internal and external spaces of the housing, and improve the heat dissipation efficiency.

[0076] The circuit board, display module, and display device provided by the present disclosure will be described below with reference to the drawings and through some embodiments.

[0077] Figure 1 It is a schematic diagram of a lamp board exemplified by the present disclosure. Figure 2 It is a schematic diagram of the area division of a light-emitting unit exemplified by the present disclosure.

[0078] For example, Figure 1 Four lamp boards are shown. One light-emitting unit 10A is disposed on each lamp board, and the light-emitting units 10A on the four lamp boards are arranged in a two-row and two-column arrangement. For example, the area division schematic diagram of the light source LED 11A in each light-emitting unit 10A is as Figure 2As shown, the small squares in the figure represent an LED 11A, and the multiple regions outlined by the dashed lines represent the light-emitting partitions 12A. Each light-emitting unit 10A may include multiple light-emitting partitions 12A. It can be understood that Figure 2 shows 4 dashed boxes, but it does not mean that there are only 4 light-emitting partitions 12A on the light-emitting unit 10A. The other light-emitting partitions 12A on the light-emitting unit 10A are omitted. Each light-emitting partition 12A includes one or more LEDs 11A and can be controlled independently of other light-emitting partitions 12A. For example, the multiple LEDs 11A within each light-emitting partition 12A are linked, that is, the current passed through by the multiple LEDs 11A located within the same light-emitting partition 12A is the same, so that the light-emitting brightness is basically the same.

[0079] Such as Figure 2 shown, this light-emitting unit includes multiple light-emitting partitions 12A. For example, this light-emitting unit can be driven by a local dimming method. For example, Figure 2 shows a light-emitting unit including 12 light-emitting partitions 12A, and each light-emitting partition 12A includes 24 LEDs 11A, but the present disclosure does not limit this.

[0080] Figure 3 is a schematic diagram of the main board driving architecture of a light-emitting unit exemplified by the present disclosure. Figure 4 is a schematic diagram of the secondary board driving architecture of a light-emitting unit exemplified by the present disclosure.

[0081] Such as Figure 3 and Figure 4 shown, 2 constant current boards correspondingly control 4 light-emitting units 10A, and each constant current board controls 1 corresponding light-emitting unit 10A. Combining with some of the foregoing embodiments, the anode voltage of the 24 LEDs 11A in each light-emitting partition 12A requires approximately 72V at most.

[0082] For example, each constant current board is boosted by a boost converter and is constantly current-regulated by an LED driver. Among the 2 constant current boards, a micro control unit (MCU) is also provided on the main board. The micro control unit is used to control the LED driver to adjust the LED current and establish communication between the main board constant current board and another secondary board constant current board.

[0083] Such as Figure 3As shown, there are two boost converters 011, two buck converters 012 (Buck Converter), and two sets of LED drivers 013 on the main board 010. For example, the main board 010 includes input interfaces CN1 to CN2 and output interfaces CN4 to CN6. The input interface CN1 on the main board 010 can receive a 24V voltage and input the voltage to the two boost converters 011 and the two buck converters 012. For example, each boost converter 011 outputs a first drive signal (e.g., high voltage) to the anode of the LED in a corresponding light-emitting unit through the output interfaces CN5 to CN6. The two sets of LED drivers 013 output a second drive signal (e.g., low voltage) to the cathode of the LED in a corresponding light-emitting unit through the output interfaces CN5 and CN6 respectively. Thus, the LED in the light-emitting unit is applied with a corresponding drive voltage (e.g., the drive voltage is the difference voltage between the first drive signal and the second drive signal), so that the corresponding drive current flows through and emits light. The micro control unit 014 is used to control the LED driver 013 to drive the conduction or turn-off of each corresponding light-emitting partition 12A, and is also used to control the magnitude of the current during conduction, so as to realize the local dimming of the two light-emitting units 10A controlled by the main board 010. The buck converter 012a is used to step down the 24V high voltage input by the input interface CN1 to 12V low voltage to supply power to the LED driver 013, and the buck converter 012b is used to step down the 12V low voltage to 3.3V to supply power to the micro control unit 014.

[0084] As Figure 4 shown, there are two boost converters 021, one buck converter 022, and two sets of LED drivers 023 on the secondary board 020. For example, the secondary board 020 includes input interfaces CN1 and CN3, and also includes output interfaces CN5 and CN6. For example, the input interface CN1 on the secondary board 020 can receive a 24V voltage. The driving principle of driving the LED to emit light in the secondary board 020 is substantially the same as that of the main board 010, and the driving method of the aforementioned main board 010 can be referred to. For example, the micro control unit 014 on the main board 010 transmits the backlight data to the LED driver 023 through three sets of Serial Peripheral Interface (SPI). The first set of SPI1 is used to receive the local dimming data through the input interface CN2, and after processing, it is sent to the LED driver 013 on the main board 010 through the second set of SPI2, and at the same time, it is sent to the LED driver 023 of the secondary board 020 through the third set of SPI3 through the input interface CN3, so as to correspond to the LEDs in different partitions.

[0085] For example, the drive current output through output interfaces CN5 to CN6 can be obtained by a conventional algorithm in the art, and the opening time of output interfaces CN5 to CN6 can be obtained according to the backlight data to achieve local dimming. For example, the LED driver 023 can provide a switching control signal and an output control signal to output interfaces CN5 to CN6, thereby driving the LEDs in each backlight zone to emit light. For example, the aforementioned backlight data includes the width configuration parameter of the output control signal of output interfaces CN5 to CN6.

[0086] Figure 5 Another schematic diagram of a lamp board shown in this disclosure. Figure 6 Another schematic diagram of the area division of a light-emitting unit shown in this disclosure. Figure 7 Another schematic diagram of the main board drive architecture of a light-emitting unit shown in this disclosure. Figure 8 Another schematic diagram of the secondary board drive architecture of a light-emitting unit shown in this disclosure.

[0087] For example, Figure 5 shows that 6 light-emitting units 10A on 6 lamp boards are arranged in a three-row and two-column layout. For example, Figure 6 shows a light-emitting unit including 12 light-emitting zones 12A, and each light-emitting zone 12A includes 30 LEDs 11A. Similarly, this disclosure does not limit this. Combining with some of the foregoing embodiments, the anode voltage of the LED 11A string in each light-emitting zone 12A requires approximately 90V at most.

[0088] Such as Figure 7 and Figure 8 shown, 2 constant current boards correspondingly control 6 light-emitting units 10A, and each constant current board controls 3 light-emitting units. To achieve the control of 3 light-emitting units by each constant current board, as Figure 7 shown, 3 boost converters 011 and 3 groups of LED drivers 013 are provided on the main board 010. As Figure 8 shown, 3 boost converters 021 and 3 groups of LED drivers 023 are provided on the secondary board 020. For the specific driving principle of the light-emitting unit, reference can be made to the relevant description of driving 4 light-emitting units 10A above, and details will not be elaborated here.

[0089] Figure 9 A schematic diagram of a light-emitting unit drive circuit shown in this disclosure.

[0090] For example, such as Figure 9As shown, the light-emitting unit driving circuit 100 includes a voltage conversion unit 110 and a light-emitting driving unit 120. The voltage conversion unit 110 is configured to output a voltage. The light-emitting driving unit 120 is connected to the output end of the voltage conversion unit 110 and is configured to drive the light-emitting unit. The voltage conversion unit 110 includes an inductor module 111, a switching element 112, a diode module 113, an output capacitor 114, and an input capacitor 115. The inductor module 111 includes a first inductor L1 and a second inductor L2 connected in parallel. The diode module 113 includes a first diode D1 and a second diode D2 connected in parallel. The input capacitor 115 is used to reduce the impedance caused by the parasitic inductance on the trace to the current change. When the switching element 112 is closed, the inductor module 111 is grounded, the input voltage charges the inductor module 111, the diode module 113 is cut off, and the output capacitor 114 outputs a voltage to the light-emitting driving unit 120. When the switching element 112 is opened, the inductor module 111 discharges, the diode module 113 conducts, and the voltage across the output capacitor 114 increases. Thus, by adjusting the switching frequency and duty cycle of the switching element 112, the output voltage is regulated, thereby achieving step-up. For example, the voltage conversion unit 110 further includes a control chip 116 (Boost IC), which is configured to control the conduction and cut-off of the switching element 112.

[0091] For example, in combination with some of the foregoing examples, each light-emitting unit includes 12 light-emitting partitions, and each partition includes 24 or 30 series-connected LEDs. The light-emitting driving unit 120 includes a driving module 121 (for example, an LED driver) corresponding to 12 light-emitting partitions. For example, the light-emitting driving unit 120 further includes 12 switching tubes 122 connected between the driving module 121 and the light-emitting partitions to receive the driving signal of the driving module 121 and realize the conduction or cut-off between the driving module 121 and the light-emitting partitions.

[0092] Figure 10A It is a schematic diagram of a circuit board exemplified by the present disclosure. Figure 10B is Figure 10A A partial schematic diagram of the circuit board shown. It should be noted that, in order to more clearly show the layout of the components in the circuit board, Figure 10B only some of the components in the first driving structure are schematically shown.

[0093] For example, as Figure 10A shown, the circuit board includes a substrate 200 and as Figure 9The illustrated light-emitting unit driving circuit 100 is disposed on a substrate 200. Combining with some of the foregoing embodiments, taking the example of two light-emitting unit driving circuits 100 driving six light-emitting units, to achieve each light-emitting unit driving circuit 100 driving three light-emitting units, the light-emitting unit driving circuit 100 includes a first driving structure 101, a second driving structure 102, and a third driving structure 103. Each driving structure includes a voltage conversion unit 110 and a light-emitting driving unit 120 connected to each other, and is configured to drive a corresponding light-emitting unit.

[0094] In some usage scenarios, the circuit board is installed in the display panel, and the longitudinal direction of the substrate 200 of the circuit board can extend along an edge of the display panel. For example, it can extend along the short side of the display panel. For example, when the display panel is in a normal viewing state, the circuit board can be vertically placed relative to the ground. For example, the voltage conversion units 110 in the three driving structures are centrally arranged on one side of the substrate 200 along the first direction y, and the light-emitting driving units 120 are centrally arranged on the other side of the substrate 200 along the first direction y. The first direction y is parallel to the longitudinal direction of the substrate 200. For example, the first direction y is the direction pointing from the side where the light-emitting driving unit 120 is located to the side where the voltage conversion unit 110 is located. In this way, separating the high-voltage area where the voltage conversion unit 110 is located from the low-voltage area where the light-emitting driving unit 120 is located can effectively reduce the interference effect suffered during the transmission of logic signals. For example, when the circuit board is vertically placed relative to the ground, the three voltage conversion units 110 are located on the upper side of the substrate 200, and the three light-emitting driving units 120 are located on the lower side of the substrate 200.

[0095] For the convenience of routing arrangement, the light-emitting driving units 1201 of the first driving structure 101, the light-emitting driving units 1202 of the second driving structure 102, the light-emitting driving units 1203 of the third driving structure 103, the voltage conversion units 1103 of the third driving structure 103, the voltage conversion units 1102 of the second driving structure 102, and the voltage conversion units 1101 of the first driving structure 101 are arranged in sequence along the first direction y.

[0096] As Figure 10A shown and combined with Figure 10B, taking the voltage conversion unit 1101 in the first driving structure 101 as an example for illustration, the output capacitor 114 and the inductor module 111 are disposed on both sides of the substrate 200 opposite to each other along the second direction x. For example, in combination with the foregoing example, the output capacitor 114 on the circuit board is located on the side close to the output interfaces CN5 to CN7. In the inductor module 111, the first inductor L1 and the second inductor L2 are arranged at intervals along the second direction x, and the second direction x is parallel to the substrate 200 and intersects with the first direction y. For example, the second direction x is perpendicular to the first direction y. The distance d11 between the first inductor L1 and the second inductor L2 in the second direction x is less than or equal to 0.5 mm.

[0097] The diode module 113 is located on the side close to the output capacitor 114 between the output capacitor 114 and the inductor module 111, and the distance d12 between the diode module 113 and the output capacitor 114 in the second direction x is greater than or equal to 1.2 mm. In the diode module 113, the first diode D1 and the second diode D2 are arranged at intervals along the first direction y, and the distance d13 between the first diode D1 and the second diode D2 in the first direction y is less than or equal to 0.5 mm.

[0098] The switching element 112 is located between the inductor module 111 and the diode module 113. For example, the minimum distance d14 between the switching element 112 and the diode module 113 is less than or equal to 2 mm. For example, the minimum distance d15 between the switching element 112 and the inductor module 111 is less than or equal to 2 mm.

[0099] The input capacitor 115 and the inductor module 111 are arranged at intervals in the first direction y, and the distance d16 between the inductor module 111 and the input capacitor 115 in the first direction y is greater than or equal to 3 mm. For example, in combination with the foregoing example, the input capacitor 115 on the circuit board is located on the side close to the input interface CN1.

[0100] As Figure 10A shown, in the voltage conversion unit 1102 of the second driving structure 102 and the voltage conversion unit 1103 of the third driving structure 103, the arrangement of the components is basically the same as that of the voltage conversion unit 1101 of the first driving structure 101. Of course, the arrangement of the components in the voltage conversion unit of the second driving structure and the voltage conversion unit of the third driving structure may also be different from the arrangement of the components in the voltage conversion unit of the first driving structure, and can be adjusted according to actual needs. The present disclosure does not limit this. For example, the arrangement of the components in the light-emitting driving unit in the first driving structure, the second driving structure, and the third driving structure may be as Figure 10A shown to be exactly the same, or can be adjusted according to actual needs. The present disclosure does not limit this. It should be noted that, Figure 10AA schematic diagram of the main board of the circuit board is schematically shown. Referring to the component layout of the main board, the output capacitor and the input capacitor on the secondary board of the circuit board are correspondingly arranged on the side where the output interface on the secondary board is located and the side where the input interface on the secondary board is located. The layout of other components can be basically the same as that of the components on the main board.

[0101] After testing the foregoing embodiment in the maximum power state of the components for 2 hours, it is known that the temperature of the switching element 112 is 123.6 °C, the temperatures of the first inductor L1 and the second inductor L2 are 114.6 °C, and the temperatures of the first diode D1 and the second diode D2 are 111.5 °C. The temperature of the components is too high and it is difficult to dissipate heat.

[0102] Combined with the foregoing test results, when the components with high heat generation are relatively close to each other, their heat generation will have an additive effect, resulting in an increase in the temperature of the components. In response, the inventor adjusted the layout of the components in the voltage conversion unit. At the same time, considering that the temperature of the switching element is the highest, the inventor adjusted the circuit of the voltage conversion unit to improve the problem of excessive current in the switching element.

[0103] Figure 11 A schematic diagram of another light-emitting unit driving circuit exemplified by the present disclosure.

[0104] For example, as Figure 11 shown, the light-emitting unit driving circuit 300 includes a voltage conversion unit 310 and a light-emitting driving unit 320. The voltage conversion unit 310 is configured to output a voltage. The light-emitting driving unit 320 is connected to the output end of the voltage conversion unit 310 and is configured to drive the light-emitting unit. The voltage conversion unit 310 includes an inductor module 311, a switching module 312, a diode module 313, an output capacitor 314, and an input capacitor 315. The inductor module 311 includes a first inductor L1 and a second inductor L2 connected in parallel. The diode module 313 includes a first diode D1 and a second diode D2 connected in parallel. The switching module 312 includes a first switching element Q1 and a second switching element Q2 connected in parallel. For example, in combination with some of the foregoing examples, each light-emitting unit includes 12 light-emitting zones, and each zone includes 24 or 30 series-connected LEDs. The light-emitting driving unit 320 includes a driving module 321 that can correspond one-to-one with 12 light-emitting zones. For example, the light-emitting driving unit 320 further includes 12 switching tubes 322 connected between the driving module 321 and the light-emitting zones to receive the driving signal of the driving module 321 and realize the conduction or cut-off between the driving module 321 and the light-emitting zones.

[0105] Thus, in some embodiments according to the present disclosure, the second switching element Q2 is connected in parallel with the first switching element Q1. By reducing the current borne by a single switching element, the conduction loss is reduced, thereby reducing the temperature of the switching module 312. For the driving principles of the voltage conversion unit 310 and the light-emitting driving unit 320, and the centralized arrangement manner of the voltage conversion unit 310 and the light-emitting driving unit 320 in the three driving structures, reference can be made to the foregoing embodiments and will not be elaborated herein.

[0106] Figure 12A It is a schematic diagram of another circuit board exemplified by the present disclosure. Figure 12B is Figure 12A A partial schematic diagram of the illustrated circuit board. It should be noted that, in order to more clearly show the arrangement manner of the components in the circuit board, Figure 12B only some components in the first driving structure and the second driving structure are schematically shown.

[0107] Refer to Figure 12A , along the first direction y, the light-emitting driving units 3201 of the first driving structure 301, the light-emitting driving units 3202 of the second driving structure 302, the light-emitting driving units 3203 of the third driving structure 303, the voltage conversion unit 3103 of the third driving structure 303, the voltage conversion unit 3102 of the second driving structure 302, and the voltage conversion unit 3101 of the first driving structure 301 are arranged in sequence.

[0108] As Figure 12A shown and in combination with Figure 12B , taking the voltage conversion unit 3101 in the first driving structure 301 as an example for illustration, the output capacitor 314 and the input capacitor 315 are oppositely arranged on both sides of the substrate 400 along the second direction x, thereby improving the influence of the heat generated by the power devices on them. The second direction x is parallel to the substrate 400 and intersects with the first direction y. For example, the second direction x is perpendicular to the first direction y.

[0109] The inductor module 311 is arranged on the side close to the input capacitor 315 between the input capacitor 315 and the output capacitor 314. In the inductor module 311, the first inductor L1 and the second inductor L2 are arranged at intervals along the first direction y. The distance d31 between the first inductor L1 and the second inductor L2 in the first direction y is greater than or equal to 8 millimeters. It should be noted that, Figure 12A A schematic diagram of the main board of the circuit board is schematically shown. Referring to the arrangement manner of the components on the main board, on the sub-board of the circuit board, the output capacitor and the input capacitor are correspondingly arranged on the side where the output interface is located and the side where the input interface is located, and the arrangement manner of other components can be basically the same as that of the components on the main board. For example, the voltage conversion unit 310 further includes a control chip 316 configured to control the conduction and cut-off of the switching element 312.

[0110] The diode module 313 is located on one side of the output capacitor 314 close to the output capacitor 314 between the output capacitor 314 and the inductor module 311. In the diode module 313, the first diode D1 and the second diode D2 are arranged at intervals from each other along the first direction y, and the distance d32 between the first diode D1 and the second diode D2 in the first direction y is greater than or equal to 2.2 millimeters.

[0111] The switch module 312 is located between the inductor module 311 and the diode module 313. For example, the minimum distance d33 between the switching element and the diode module 313 is greater than or equal to 3 millimeters. For example, the minimum distance d34 between the switching element and the inductor module 311 is greater than or equal to 5 millimeters. In the switch module 312, the first switching element Q1 and the second switching element Q2 are arranged at intervals from each other in the second direction x, and the distance d35 between them is greater than or equal to 0.4 millimeters.

[0112] As Figure 12A shown, in the voltage conversion unit 3102 of the second driving structure 302 and the voltage conversion unit 3103 of the third driving structure 303, the arrangement of the components is basically the same as that of the voltage conversion unit 3101 of the first driving structure 301. Referring to Figure 12B , the distance d36 between the first inductor L1 in the first driving structure 301 and the second inductor L2' in the second driving structure 302 in the first direction y is also greater than 8 millimeters, so as to ensure sufficient heat dissipation of the inductor module 311. For example, referring to Figure 12A , in the voltage conversion unit 311 in the second driving structure 302, the arrangement of the switch module 312, the diode module 313 and the output capacitor 314 is the same as the arrangement in the first driving structure 301, and the input capacitors 315 in the first driving structure 302 and the second driving structure 302 are arranged along the first direction y. For example, the arrangement of the components in the voltage conversion unit 310 in the third driving structure 303 is substantially the same as the arrangement of the components in the second driving structure 302.

[0113] Of course, the arrangement of the components in the voltage conversion unit of the second driving structure and the voltage conversion unit of the third driving structure may also be exactly the same as the arrangement of the components in the voltage conversion unit of the first driving structure, and can also be adjusted according to actual needs. The present disclosure does not limit this. For example, the arrangement of the components in the light-emitting driving unit in the first driving structure, the second driving structure and the third driving structure may be the same, or may be slightly different as Figure 12A shown, and can be adjusted according to actual needs. The present disclosure does not limit this.

[0114] For example, the substrate 400 includes a first conductive layer 410 and a first solder mask layer 420. The first conductive layer 410 and the first solder mask layer 420 are located on the side of the substrate 400 where the light-emitting unit driving circuit 300 is provided. The first conductive layer 410 is located on the side of the first solder mask layer 420 away from the light-emitting unit driving circuit 300. A first opening 421 exposing the first conductive layer 410 is formed in the first solder mask layer 420. The first conductive layer 410 can be exposed through the first opening 421 formed in the first solder mask layer 420, thereby dissipating heat. Considering the layout of traces and components on the circuit board, there are slight differences in the first opening 421 in the regions where the first driving structure 301, the second driving structure 302, and the third driving structure 303 are located. In the present disclosure, the first opening 421 in the region where the first driving structure 301 is located is taken as an example for illustration.

[0115] The first opening 421 includes a first opening portion 4211, and the first opening portion 4211 is located between the inductor module 311, the diode module 313, and the switch module 312, so as to dissipate heat from the middle position of the components and improve the heat addition effect between the components. The area of the first opening portion 4211 is greater than or equal to 320 square millimeters.

[0116] The first opening 421 includes a second opening portion 4212, and the second opening portion 4212 is located on the side of the inductor module 311 away from the switch module 412 in the second direction x, so as to cooperate with the first opening portion 4211 to dissipate heat from the inductor module 311 together. The area of the second opening portion 4212 is greater than or equal to 75 square millimeters.

[0117] The first opening 421 includes a third opening portion 4213, and the third opening portion 4213 is located on the side of the diode module 313 facing the voltage conversion unit 310 of the second driving structure 302, so as to dissipate heat from the diode module 313. The area of the third opening portion 4213 is greater than or equal to 90 square millimeters.

[0118] On the side of the substrate 400 away from the first solder mask layer 420, there are also a second conductive layer and a second solder mask layer, and the second conductive layer is located between the second solder mask layer and the first conductive layer 410. A second opening exposing the second conductive layer is formed in the second solder mask layer, and the orthographic projection of the second opening on a plane parallel to the substrate 400 covers the orthographic projection of the first opening 421 on this plane. In this way, the openings on the opposite sides of the substrate 400 correspond to each other. While the components dissipate heat through the first opening 421, the side where the second opening is located dissipates heat through the second opening, improving the heat dissipation efficiency of the circuit board.

[0119] After testing the foregoing embodiments in the maximum power state of the components for 2 hours, it is known that in the switching module 312, the temperature of the first switching element Q1 close to the inductor module 311 is relatively higher, and the temperature is 101.8 °C. Due to the influence of heat rising, in the inductor module 311, the temperature of the second inductor L2 located higher is higher, and the temperature is 96.5 °C. In the diode module 313, the temperature of the second diode D2 located between the output capacitor 314 and the second switching element Q2 is relatively higher, and the temperature is 93.0 °C. Compared with the foregoing embodiments, the temperature of the improved switching module 312 drops by 21.8 °C, the temperature of the inductor module 311 drops by 18.1 °C, and the temperature of the diode module 313 drops by 18.5 °C.

[0120] Figure 13A Schematic diagram of the light-emitting unit driving circuit provided by at least one embodiment of the present disclosure.

[0121] Reference Figure 13A , at least one embodiment of the present disclosure provides a light-emitting unit driving circuit 500, including a voltage conversion unit 510 and a light-emitting driving unit 520. For example, the voltage conversion unit 510 is a DC-DC converter. For example, the voltage conversion unit 510 is a Boost boost circuit and can generate an output voltage higher than the input voltage. For example, the light-emitting driving unit 520 is an LED Driver. The voltage conversion unit 510 includes an input end and an output end and is configured to output a preset voltage. For example, the voltage conversion unit 510 adjusts the voltage to the preset voltage by controlling the duty cycle, so as to output the preset voltage from the output end of the voltage conversion unit 510. The light-emitting driving unit 520 is connected to the output end of the voltage conversion unit 510 and is configured to drive the light-emitting unit. The voltage conversion unit 510 outputs a preset voltage to the light-emitting driving unit 520, thereby adjusting the brightness of the light-emitting unit. For example, in combination with some of the foregoing examples, each light-emitting unit includes 12 light-emitting partitions, and each partition includes 24 or 30 series-connected LEDs. The light-emitting driving unit 520 includes a driving module 521 that can correspond to the 12 light-emitting partitions one by one. For example, the light-emitting driving unit 520 further includes 12 switching tubes 522 connected between the driving module 521 and the light-emitting partitions to receive the driving signal of the driving module 521 and realize the conduction or cut-off between the driving module 521 and the light-emitting partitions.

[0122] Such as Figure 13AAs shown, the voltage conversion unit 510 includes an inductor module 511, a diode module 513, a switch module 512, and an output capacitor module 514. For example, during the charging process, the switch module 512 is closed, the input voltage flows through the inductor module 511, the diode module 513 prevents the output capacitor module 514 from discharging to the ground, and the current on the inductor module 511 linearly increases to store energy in the inductor module 511. For example, during the discharging process, the switch module 512 is opened, the inductor module 511 discharges to charge the output capacitor module 514, and the voltage across the output capacitor module 514 increases, realizing the step-up of the voltage conversion unit 510. For example, the voltage conversion unit 510 further includes a control chip 516 configured to control the conduction and cutoff of the switching element 512.

[0123] As Figure 13A shown, the inductor module 511 is connected between the input end of the voltage conversion unit 510 and the positive electrode of the diode module 513, and the negative electrode of the diode module 513 is connected to the output end of the voltage conversion unit 510. For example, referring to Figure 13A , one end of the inductor module 511 close to the input end of the voltage conversion unit 510 is used to apply the input voltage Vin and is electrically connected to the input capacitor module 515. The other end of the inductor module 511 is electrically connected to one end of the switch module 512 (in combination with the following example, for example, one of the input end and the output end of the switch module 512), and the other end of the switch module 512 (in combination with the following example, for example, the other of the input end and the output end of the switch module 512) is used to apply the ground voltage GND. For example, the inductor module 511 is used to convert electrical energy into magnetic energy for storage when the switch module 512 is conducting, and when the switch module 512 is opened, the inductor module 511 converts the stored magnetic field into electrical energy. The electrical energy converted by the inductor module 511 is superimposed on the input voltage, and after filtering by the diode module 513 and the output capacitor module 514, a smooth DC voltage is output.

[0124] For example, the anode of the diode module 513 is electrically connected to one end of the switch module 512 (in combination with the following example, for example, one of the input end and the output end of the switch module 512); the cathode of the diode module 513 is electrically connected to the output end of the voltage conversion unit 510 and is connected to the output capacitor module 514. Thus, by controlling the conduction and cutoff of the switch module 512, the output voltage Vout of the voltage conversion unit 510 can be made higher than the input voltage Vin.

[0125] For example, the forward conduction direction of the diode module 513 is from the input end to the output capacitor module 514. For example, the diode module 513 plays an isolation role in the voltage conversion unit 510. When the switch module 512 is turned on, the positive voltage of the diode module 513 is higher than the negative voltage, and the diode module 513 is reversely cut off. The energy storage process of the inductor module 511 will not affect the power supply output of the output capacitor module 514, reducing the conduction loss of the switch module 512. When the switch module 512 is turned off, the energy obtained by superimposing the electric field energy converted by the inductor module 511 and the input voltage is supplied to the output end of the voltage conversion unit 510 through the diode module 513.

[0126] As Figure 13A shown, the switch module 512 includes a control end, an input end, and an output end. The control end of the switch module 512 is configured to receive a control signal, and the control signal is used to control the conduction or cut-off between the input end and the output end of the switch module 512. One of the input end and the output end of the switch module 512 is connected between the inductor module 511 and the diode module 513, and the other of the input end and the output end of the switch module 512 is connected to the ground end. For example, when the control end of the switch module 512 receives a conduction control signal, the input end and the output end of the switch module 512 are turned on, and the voltage conversion unit 510 starts the charging process, and the input voltage charges the inductor module 511. For example, when the control end of the switch module 512 receives a cut-off control signal, the input end and the output end of the switch module 512 are cut off, and the voltage conversion unit 510 starts the discharging process, and the energy stored in the inductor module 511 discharges through the diode module 513.

[0127] As Figure 13A shown, the first pole of the output capacitor module 514 is connected to the negative pole of the diode module 513, and the second pole of the output capacitor module 514 is connected to the ground end. The output capacitor module 514 can reduce the AC ripple coefficient and smooth the DC output. For example, the first pole of the output capacitor module 514 is the positive pole, and the second pole is the negative pole.

[0128] Figure 14 The figure is a schematic diagram of a light-emitting unit driving circuit provided by another example of the present disclosure.

[0129] As Figure 13A and Figure 14 shown, the switch module 512 includes at least a first switching element Q1 and a second switching element Q2 connected in parallel. For example, the switch module 512 includes a first switching element Q1, a second switching element Q2, and a third switching element Q3 connected in parallel. Combining with some of the foregoing embodiments, as in Figure 14As shown, when there is only one output capacitor in the output capacitor module 514, the heat generation of the switch module 512 is high, and it is difficult to reduce the temperature of each switching element. By the first switching element Q1, the second switching element Q2, and the third switching element Q3 connected in parallel, the current on a single switching element can be reduced, thereby reducing the conduction loss.

[0130] For example, the first switching element Q1, the second switching element Q2, and the third switching element Q3 are reserved in the voltage conversion unit 510. First, the first switching element Q1 and the second switching element Q2 are connected in parallel. When it is difficult to continue reducing the temperature after connecting two switching elements in parallel, the third switching element Q3 is then connected in parallel to continue reducing the temperature of each switching element.

[0131] For example, at least one of the first switching element Q1 and the second switching element Q2 is a transistor. It should be noted that the transistors used in the embodiments of the present disclosure can all be field effect transistors or other switching components with the same characteristics. In the embodiments of the present disclosure, field effect transistors are taken as examples for illustration.

[0132] Figure 13B It is a schematic diagram of the principle of the voltage conversion unit in the light-emitting unit driving circuit provided by an example of the present disclosure.

[0133] Reference Figure 13B , taking the switch module 512 as a field effect transistor (power MOSFET) as an example for illustration. For example, the voltage conversion unit 510 further includes a control module CTR (for example, the control module CTR is the Figure 13A control chip 516 shown) connected to the control terminal of the power MOSFET. The control module CTR is configured to provide a control signal capable of controlling the conduction and turn-off of the power MOSFET; the control signal includes a high-level signal and a low-level signal. The voltage value of the high-level signal in the control signal is 0.5 to 0.8 times the maximum rated value of the gate-source voltage of the power MOSFET.

[0134] In an example of the present disclosure, the high-level signal of the control signal provided by the control module CTR has a relatively high voltage value, which can enable the power MOSFET to maintain a higher gate-source voltage when conducting, thereby reducing the static loss of the power MOSFET, especially significantly reducing the conduction loss of the power MOSFET, and further greatly reducing the power consumption of the power MOSFET and the heat dissipation of the power MOSFET, avoiding excessive temperature rise of the power MOSFET and the voltage conversion unit. In this example, when the high-level signal of the control signal is applied to the control terminal of the power MOSFET, the gate-source voltage of the power MOSFET is basically equal to (without considering voltage drop) the voltage value of the high-level signal; the voltage value of the high-level signal of the control signal is set to 0.5 to 0.8 times the maximum rated value of the gate-source voltage of the power MOSFET, which can not only ensure the safety of the power MOSFET but also increase the gate-source voltage of the power MOSFET when conducting as much as possible. In this way, the voltage conversion unit can reduce the loss and heat generation of the power MOSFET while ensuring the safety of the power MOSFET.

[0135] For example, the power MOSFET loss mainly includes static loss and dynamic loss. Among them, the static loss includes conduction loss (also known as electrical conduction loss) and cut-off loss (also known as turn-off loss). The dynamic loss mainly includes switching loss, gate drive loss, built-in diode forward loss (also called freewheeling loss), internal diode reverse loss, etc. The zero-gate-voltage leakage current of the power MOSFET is small, so the cut-off loss is not the main loss factor of the power MOSFET. The total gate charge of the power MOSFET and the reverse recovery charge of the PN junction of the internal diode are also very small, so the gate drive loss and the internal diode reverse loss are not the main loss factors of the power MOSFET.

[0136] For example, the largest share of the power MOSFET loss lies in the conduction loss. By reducing the static impedance of the power MOSFET when conducting, the conduction loss of the power MOSFET can be reduced; at the same time, increasing the gate-source voltage of the power MOSFET when conducting can also reduce the turn-on loss of the power MOSFET. In this way, the voltage conversion unit 510 can reduce the loss of the power MOSFET and lower the temperature of the power MOSFET.

[0137] For example, the voltage value of the high-level signal in the control signal is 0.6 to 0.7 times the maximum rated value of the gate-source voltage of the power MOSFET. For example, when the maximum rated value of the gate-source voltage of the power MOSFET is 20V, the voltage value of the high-level signal in the control signal can be made 12 to 14V, so that the gate-source voltage of the power MOSFET when conducting is in the range of 12 to 14V.

[0138] For example, a control signal for controlling the on and off of the power MOSFET can be provided by the control module CTR; the control signal includes a high-level signal and a low-level signal. The voltage value of the high-level signal of the control signal output by the control module CTR is often relatively low, for example, generally between 4V and 8V. Although the high-level signal is sufficient to turn on the power MOSFET, due to the insufficient gate-source voltage of the power MOSFET, the power MOSFET will have a large on-resistance, resulting in a large on-loss of the power MOSFET and serious heating, and the temperature of the power MOSFET is relatively high. In the example of the present disclosure, on the premise of ensuring the safety of the power MOSFET, the gate-source voltage of the power MOSFET during conduction can be increased as much as possible. For example, the gate-source voltage of the power MOSFET during conduction can be increased to 12V to 14V, so as to achieve the purpose of reducing the on-loss of the power MOSFET, reducing the heating of the power MOSFET, and reducing the temperature of the power MOSFET.

[0139] It can be understood that in the above example, only the maximum rated value of the gate-source voltage of the power MOSFET is 20V as an example, and the gate-source voltage of the power MOSFET during conduction is exemplarily described. In other examples of the present disclosure, the maximum rated value of the gate-source voltage of the power MOSFET may not be 20V, for example, it may be 25V, 30V, etc. Further, the maximum rated value of the gate-source voltage of the power MOSFET can be obtained by querying the parameter manual of the power MOSFET.

[0140] The inventor found in the research that referring to Figure 13A and Figure 14 , on the basis of paralleling the first switching element Q1 and the second switching element Q2, further paralleling the third switching element Q3, the temperature change of each switching element is relatively small. It can be seen that in the voltage conversion unit 510 in the example of the present disclosure, the influence on the temperature of the switching module 512 mainly comes from the switching loss, and the influence of the on-loss is not significant. In addition, when the distance between the components with high heat generation is relatively small, the heat generation between the components will have an additive effect, which will also cause the temperature of the components to rise. Based on this, the switching module 512 only includes the first switching element Q1 and the second switching element Q2 connected in parallel. In this way, not only can the on-loss be reduced, but also the distance between the components can be increased, so as to reduce the temperature of the switching module 512 by increasing the distance and combining with reducing the on-loss.

[0141] For example, a switching component with a larger package can also be selected to reduce the temperature rise of the switching module 512, and the present disclosure does not limit this here. For example, the switching loss can also be reduced by selecting a switching component with a smaller switching loss. Although the cost will increase accordingly, the temperature of the switching module 512 can also be reduced, and the present disclosure does not limit this here.

[0142] As shown Figure 13A in FIG. 514, the output capacitance module 514 includes at least a first output capacitor C1 and a second output capacitor C2 connected in parallel. Since the output current of the voltage conversion unit 510 fluctuates continuously, the temperature of the output capacitance module 514 increases. By connecting the first output capacitor C1 and the second output capacitor C2 in parallel, the current on each component is reduced, thereby reducing the temperature of the first output capacitor C1 and the second output capacitor C2, increasing the service life of the capacitance module, and at the same time reducing the output voltage current ripple and improving the output stability.

[0143] For example, the inductance module 511 includes at least a first inductor L1 and a second inductor L2 connected in parallel. By connecting the first inductor L1 and the second inductor L2 in parallel, the current flowing through the first inductor L1 and the second inductor L2 can be reduced, thereby reducing the temperature of the inductance module 511. For example, an inductor component with a larger package can also be selected to reduce the temperature rise of the inductance module 511, which is not limited in this disclosure.

[0144] For example, the diode module 513 includes at least a first diode D1 and a second diode D2 connected in parallel. Connecting the first diode D1 and the second diode D2 in parallel can reduce the temperature of each component, thereby reducing the temperature of the diode module 513. For example, at least one of the first diode D1 and the second diode D2 is a Schottky diode. The Schottky diode has a high current density and a low forward voltage drop, that is, the Schottky diode consumes less power and generates less heat. For example, a diode component with a larger package can also be selected to reduce the temperature rise of the diode module 513, which is not limited in this disclosure.

[0145] Referring Figure 13B to FIG. 400, for example, the control module CTR is further configured such that when providing a sink current to the control terminal of the power MOSFET, the maximum value of the sink current is not less than 0.5 A, for example, between 1 A and 2 A. In this way, the control module CTR can provide a large sink current to the power MOSFET, thereby further reducing the turn-on loss of the power MOSFET and facilitating the reduction of the temperature of the power MOSFET. It can be understood that when the control module CTR provides a sink current to the control terminal of the power MOSFET, the magnitude of the sink current is dynamically variable rather than a constant current.

[0146] Referring Figure 13B to FIG. 403, the voltage conversion unit 510 may further include a gate resistor Rg. The first end of the gate resistor Rg is electrically connected to the output terminal of the control module CTR, and the second end of the gate resistor Rg is electrically connected to the control terminal of the power MOSFET. In this way, when the control module CTR loads a high-level signal to the control terminal of the power MOSFET, the gate resistor Rg can also control the sink current together to prevent the sink current from being too large instantaneously and damaging the power MOSFET.

[0147] Figure 13C Schematic diagram of the principle of the voltage conversion unit in the light-emitting unit driving circuit provided by another example of the present disclosure. Figure 13D Schematic diagram of the principle of the control module in the voltage conversion unit provided by an example of the present disclosure. Figure 13E Equivalent circuit diagram of the control module provided by an example of the present disclosure.

[0148] Reference Figure 13C Figure 13C , the voltage conversion unit 510 may further include a diode D'. The anode of the diode D' is electrically connected to the second end of the gate resistor Rg, and the cathode of the diode D' is electrically connected to the first end of the gate resistor Rg. When the control signal output by the control module CTR is a low-level signal, the control end of the power MOSFET can discharge through the diode D' and the gate resistor Rg; at this time, the diode D' conducts, so that the power MOSFET has a large extraction current, which can reduce the turn-off loss of the power MOSFET.

[0149] Reference Figure 13D Figure 13D , for example, the control module CTR may include a voltage stabilizing unit U1, and the voltage stabilizing unit U1 is configured to provide a driving voltage, and the driving voltage is not less than the voltage of the high-level signal in the control signal. The control module CTR can use the driving voltage to make the high-level signal of the output control signal have a higher voltage value, so as to achieve the purpose of increasing the gate-source voltage of the power MOSFET when it is turned on, and overcome the problem that the voltage value of the high-level signal of the control signal directly output by the control chip 516 is too low. For example, the voltage stabilizing unit U1 can output a driving voltage according to the input voltage Vin. In this way, the power supply on the driving circuit board can supply power to the inductor module 511 and the voltage stabilizing unit U1 at the same time, which is beneficial to simplifying the circuit of the driving circuit board and reducing the cost of the driving circuit board. Of course, in other examples of the present disclosure, the voltage stabilizing unit U1 can also generate a driving voltage using other power supply voltages.

[0150] For example, reference Figure 13E, the voltage stabilizing unit U1 includes a first switching element Q1, a voltage stabilizing diode ZD1, a first resistor R1, and a filtering sub-circuit C1. The first end of the first switching element Q1 is used to load the input voltage Vin, and the second end of the first switching element Q1 is electrically connected to the output end of the voltage stabilizing unit U1; a first resistor R1 is connected between the control end of the first switching element Q1 and the first end of the first switching element Q1, and the control end of the first switching element Q1 is electrically connected to the cathode of the voltage stabilizing diode ZD1, and the anode of the voltage stabilizing diode ZD1 is used to load the ground voltage GND; the filtering sub-circuit C1 is electrically connected to the output end of the voltage stabilizing unit U1. In this example, the first switching element Q1, the voltage stabilizing diode ZD1, and the first resistor R1 form a voltage regulator, and the filtering sub-circuit C1 can filter the output of the voltage regulator to filter out the AC components. An appropriate voltage stabilizing diode ZD1 can be selected according to the magnitude of the required driving voltage. For example, when the maximum rated value of the gate-source voltage of the power MOSFET is 20V and the derating factor used is 0.6 to 0.7, a voltage stabilizing diode ZD1 with a stable voltage of 12V to 14V can be selected. It can be understood that when selecting the first switching element Q1, the first resistor R1, and the voltage stabilizing diode ZD1, the specifications of the first switching element Q1, the first resistor R1, and the voltage stabilizing diode ZD1 (such as current specifications, power specifications, voltage specifications, etc.) can also be verified to avoid damage to the first switching element Q1, the first resistor R1, and the voltage stabilizing diode ZD1 during operation due to non-compliance with the requirements.

[0151] It can be understood that multiple different strategies can be adopted to use the voltage stabilizing unit U1 to generate a control signal and make the voltage value of the high-level signal of the control signal relatively high, and even make the control module CTR provide a large sinking current for the control end of the power MOSFET.

[0152] Reference Figure 13D and Figure 13E , for example, the control module CTR includes a driving chip DIC, a voltage stabilizing unit U1, an inverting unit U2, and a driving unit U3. The driving chip DIC is configured to provide an initial control signal, and the initial control signal includes a high-level signal and a low-level signal. The voltage stabilizing unit U1 is configured to provide a driving voltage, and the driving voltage is not less than the voltage of the high-level signal in the control signal. The inverting unit U2 includes a second resistor R2 and a second switching element Q2. The first end of the second resistor R2 is electrically connected to the output end of the voltage stabilizing unit U1, the second end of the second resistor R2 and the first end of the second switching element Q2 are electrically connected to the first node N1, and the second end of the second switching element Q2 is used to load the ground voltage GND.

[0153] The driving chip DIC has an output terminal GATE of the driving chip for outputting an initial control signal, and the control terminal of the second switching element Q2 is electrically connected to the output terminal of the driving chip. Thus, the control terminal of the second switching element Q2 can receive the initial control signal sent by the driving chip DIC. The second switching element Q2 is configured to conduct in response to a high-level signal in the initial control signal and turn off in response to a low-level signal in the initial control signal. When the second switching element Q2 conducts, the voltage of the first node N1 is pulled down to the ground voltage GND and is at a low level; when the second switching element Q2 turns off, the voltage of the first node N1 is pulled up by the voltage stabilizing unit U1 and is at a high level.

[0154] The first end of the driving unit U3 is electrically connected to the output terminal of the voltage stabilizing unit U1, and the second end of the driving unit U3 is used to load the ground voltage GND. The control terminal of the driving unit U3 is electrically connected to the first node N1, and the output terminal of the driving unit U3 is electrically connected to the control terminal of the power MOSFET. The driving unit U3 is configured to conduct between the first end of the driving unit U3 and the control terminal of the power MOSFET when the voltage of the first node N1 is at a low level (at this time, the driving unit U3 outputs a high-level signal of the control signal), and conduct between the second end of the driving unit U3 and the control terminal of the power MOSFET when the voltage of the first node N1 is at a high level (at this time, the driving unit U3 outputs a low-level signal of the control signal).

[0155] Thus, when the voltage of the first node N1 is at a low level, the driving voltage can be written into the control terminal of the power MOSFET (that is, provide a sink current to charge the control terminal of the power MOSFET), so that the power MOSFET conducts, and the power MOSFET has a large gate-source voltage when conducting. Moreover, since the driving voltage has a large voltage value, the driving unit U3 can provide a large sink current for the control terminal of the power MOSFET. Overall, when the initial control signal output by the driving chip DIC is a high-level signal, the control signal output by the driving unit U3 is a high-level signal. On the contrary, when the voltage of the first node N1 is at a high level, the ground voltage GND can be written into the control terminal of the power MOSFET through the driving unit U3 (that is, provide a source current to discharge the control terminal of the power MOSFET), thereby turning off the power MOSFET. During this process, the control terminal of the power MOSFET discharges, which is equivalent to the driving unit U3 providing a source current for the control terminal of the power MOSFET. Overall, when the initial control signal output by the driving chip DIC is a low-level signal, the control signal output by the driving unit U3 is a low-level signal. Thus, the control signal output by the driving unit U3 is synchronized with the initial control signal output by the driving chip DIC.

[0156] In this example, the inverting unit U2 and the driving unit U3 together constitute a level conversion sub-circuit, which converts the high-level voltage of the initial control signal output by the driving chip DIC into the gate driving voltage required by the power MOSFET; the driving unit U1 provides the sink current in the gate driving current required by the power MOSFET, and the gate driving current also includes the draw current (also referred to as the drain current).

[0157] Figure 13F Schematic diagram of the principle of the control module in the voltage conversion unit provided by another example of the present disclosure. Figure 13G Equivalent circuit schematic diagram of the control module provided by another example of the present disclosure.

[0158] Refer to Figure 13F and Figure 13G , for example, the control module CTR includes a driving chip DIC, a voltage stabilizing unit U1, and a driving unit U3. The voltage stabilizing unit U1 is configured to provide a driving voltage, and the driving voltage is not less than the voltage of the high-level signal in the control signal. The driving chip DIC is a control chip capable of utilizing an externally supplied voltage, and is configured to be able to output an initial control signal according to the driving voltage provided by the voltage stabilizing unit U1. The first end of the driving unit U3 is electrically connected to the output end of the voltage stabilizing unit U1, and the second end of the driving unit U3 is used to load the ground voltage GND; the control end of the driving unit U3 is configured to receive the initial control signal, and the output end of the driving unit U3 is electrically connected to the gate of the power MOSFET. The driving unit U3 is configured to make the electrical connection between the first end of the driving unit U3 and the power MOSFET conductive in response to the high-level signal in the initial control signal, and make the electrical connection between the second end of the driving unit U3 and the power MOSFET conductive in response to the low-level signal in the initial control signal.

[0159] In this example, the high-level signal of the initial control signal output by the driving chip DIC has a sufficiently high voltage value, so it is sufficient to directly drive the driving unit U3. Therefore, the control module CTR of this example does not need to be provided with an inverting unit U2, and thus the cost of the control module CTR can be reduced.

[0160] For example, refer to Figure 13F and Figure 13G, the driving unit U3 includes a third switching element Q3 and a fourth switching element Q4. The first end of the third switching element Q3 is electrically connected to the output end of the voltage stabilizing unit U1, and the first end of the fourth switching element Q4 is used to load the ground voltage GND; the control ends of the third switching element Q3 and the fourth switching element Q4 are configured to receive an initial control signal, and the second ends of the third switching element Q3 and the fourth switching element Q4 are electrically connected to the second node N2, and the second node N2 is electrically connected to the control end of the power MOSFET, for example, electrically connected to the control end of the power MOSFET through the gate resistor Rg. The third switching element Q3 is configured to conduct in response to a high-level signal in the initial control signal and cut off in response to a low-level signal in the initial control signal. The fourth switching element Q4 is configured to conduct in response to a low-level signal in the initial control signal and cut off in response to a high-level signal in the initial control signal.

[0161] For example, referring to Figure 13F and Figure 13G , the control module CTR includes a driving chip DIC and a voltage stabilizing unit U1. The voltage stabilizing unit U1 is configured to provide a driving voltage, and the driving voltage is not less than the voltage of the high-level signal in the control signal; the driving chip DIC is a control chip capable of using an externally injected voltage, and it is configured to output a control signal according to the driving voltage. In this example, the initial control signal output by the driving chip DIC can be directly loaded onto the control end of the power MOSFET as the control signal without the need to adjust the voltage or current by means of the driving unit U3.

[0162] Exemplarily, referring to Figure 13F and Figure 13G , the driving chip DIC has an externally injected voltage terminal VCC for loading the externally injected voltage and an output terminal GATE for outputting a control signal. The output end of the voltage stabilizing unit U1 can be electrically connected to the externally injected voltage terminal VCC, so that the driving voltage is loaded onto the driving chip DIC as the externally injected voltage. The driving chip DIC can output a control signal from the output terminal GATE according to the externally injected voltage instead of outputting a control signal according to an internal constant voltage, which makes the high-level signal of the control signal have a high voltage value. The output terminal GATE can be electrically connected to the control end of the power MOSFET, for example, electrically connected to the control end of the power MOSFET through the gate resistor Rg.

[0163] In this example, the driving chip DIC can generate a control signal according to the externally supplied voltage (driving voltage) provided by the voltage stabilizing unit U1. The high-level signal of this control signal has a relatively high voltage value, so the conduction loss at the control terminal of the power MOSFET can be greatly reduced. In particular, when the control requirements for the temperature rise of the DC-DC boost circuit are not very strict, the control module CTR in this example can omit the inverting unit U2 and the driving unit U3, thereby reducing the cost of the control module CTR.

[0164] It can be understood that, as Figures 13A to 13G shown in the light-emitting unit driving circuit, it can be applied to the circuit board in the present disclosure.

[0165] Figure 15A Schematic diagram of one side surface of the circuit board provided by at least one embodiment of the present disclosure. Figure 15B Schematic diagram of the other side surface of the circuit board provided by at least one embodiment of the present disclosure. Figure 15C is Figure 15A Partial schematic diagram of the circuit board shown. Figure 15D is Figure 15A Planar schematic diagram of the circuit board shown. Figure 16 Schematic diagram of the light-emitting unit driving circuit provided by another example of the present disclosure. It should be noted that, in order to more clearly show the arrangement of components in the circuit board, Figure 15C only some components in the first driving structure are schematically shown, Figure 15D only some components on the circuit board are schematically shown.

[0166] Referring to Figures 15A to 16 , at least one embodiment of the present disclosure further provides a circuit board, including a substrate 600 and a light-emitting unit driving circuit 500. The light-emitting unit driving circuit 500 is disposed on the substrate 600, and the light-emitting unit driving circuit 500 includes a voltage conversion unit 510 and a light-emitting driving unit 520. For example, the voltage conversion unit 510 is a DC-DC converter. For example, the voltage conversion unit 510 is a Boost boost circuit and can generate an output voltage higher than the input voltage. For example, the light-emitting driving unit 520 is an LED Driver. The voltage conversion unit 510 includes an input end and an output end, and is configured to output a preset voltage. The light-emitting driving unit 520 is connected to the output end of the voltage conversion unit 510 and is configured to drive the light-emitting unit. For example, the voltage conversion unit 510 adjusts the voltage to the preset voltage by controlling the duty cycle, so as to output the preset voltage from the output end of the voltage conversion unit 510. The light-emitting driving unit 520 is connected to the output end of the voltage conversion unit 510 and is configured to drive the light-emitting unit. The voltage conversion unit 510 outputs a preset voltage to the light-emitting driving unit 520, thereby adjusting the brightness of the light-emitting unit.

[0167] As Figure 15A and Figure 16 shown, a plurality of voltage conversion units 510 are provided, and a plurality of light emission driving units 520 are provided. The plurality of voltage conversion units 510 and the plurality of light emission driving units 520 are provided in one-to-one correspondence, and the corresponding voltage conversion unit 510 and light emission driving unit 520 are connected to each other to form a plurality of driving structures. For example, three voltage conversion units 510 are provided, and three light emission driving units 520 are provided. The corresponding voltage conversion unit 510 and light emission driving unit 520 are connected to form three driving structures.

[0168] For example, the voltage conversion units in the plurality of driving structures are centrally arranged on one side of the substrate, and the light emission driving units in the plurality of driving structures are centrally arranged on the other side of the substrate. In this way, the high-voltage area where the voltage conversion units are located is separated from the low-voltage area where the light emission driving units are located, and the interference effect received during the transmission of logic signals can be effectively reduced.

[0169] For example, the plurality of driving structures include three driving structures arranged in sequence along the longitudinal direction of the substrate. For example, the three driving structures are a first driving structure, a second driving structure, and a third driving structure, and the light emission driving units of the first driving structure, the light emission driving units of the second driving structure, and the light emission driving units of the third driving structure are arranged in sequence along the first direction. At the same time, for the convenience of routing layout, the voltage conversion units of the third driving structure, the voltage conversion units of the second driving structure, and the voltage conversion units of the first driving structure are arranged in sequence along the first direction.

[0170] In some usage scenarios of the circuit board, the surface of the substrate 600 is arranged at an angle with the ground. For example, the surface of the substrate 600 is perpendicular to the ground. For example, for the convenience of heat dissipation, the voltage conversion unit 510 is arranged on the side of the substrate 600 away from the ground.

[0171] As Figure 15A and Figure 16 shown, the plurality of driving structures are arranged in sequence along the first direction y, and the plurality of light emission driving units 520 and the plurality of voltage conversion units 510 are alternately arranged along the first direction y. The first direction y is parallel to the surface of the substrate 600. For example, the size of the substrate 600 in the first direction y is greater than the size of the substrate 600 in the second direction x. The second direction x intersects with the first direction y and is parallel to the surface of the substrate 600. For example, the first direction y is the longitudinal direction of the substrate 600, and the second direction x is the width direction of the substrate 600. For example, the second direction x is perpendicular to the first direction y.

[0172] For example, in the first direction y, three driving structures are arranged in sequence, so that the voltage conversion unit 510 and the light-emitting driving unit 520 are arranged alternately. For example, the multiple driving structures include a first driving structure 501, a second driving structure 502, and a third driving structure 503. The light-emitting driving unit 5201 in the first driving structure 501 is adjacent to the voltage conversion unit 5102 in the second driving structure 502, and the light-emitting driving unit 5202 in the second driving structure 502 is adjacent to the voltage conversion unit 3103 in the third driving structure 503. By arranging the voltage conversion unit 510 and the light-emitting driving unit 520 alternately, heat-generating components can be dispersed, improving the additive effect of heat generation between components. Moreover, considering that heat propagates upward away from the ground, resulting in a relatively higher overall temperature of the voltage conversion unit 510 located higher up, the dispersed arrangement can also reduce the additive effect of heat generation between components.

[0173] For example, the light-emitting unit includes a plurality of serially connected light-emitting diodes to form a plurality of light-emitting diode strings. The number of light-emitting diode strings is greater than the number of driving structures, and each driving structure is connected to two or more light-emitting diode strings among the plurality of light-emitting diode strings. For example, in combination Figure 6 and Figure 16 as shown, 30 light-emitting diodes are connected in series to form a light-emitting diode string, and each light-emitting unit includes 12 strings of light-emitting diode strings. The light-emitting driving unit 520 in each driving structure includes 12 driving modules 521, and each driving module 521 drives a corresponding string of light-emitting diode strings.

[0174] For example, the light-emitting driving unit 520 further includes 12 switching tubes 522 connected between the driving module 521 and the light-emitting partition to receive the driving signal of the driving module 521 and realize conduction or cut-off between the light-emitting driving unit 520 and the light-emitting partition. As Figure 15A shown, the 12 switching tubes 522 are arranged on the substrate 400 in a two-row and six-column manner, making it easy to dissipate heat. For example, the two rows of switching tubes 522 are staggered to increase the distance between adjacent two switching tubes 522.

[0175] For example, the circuit board further includes a shielding component, and the shielding component is at least arranged on the opposite sides of the light-emitting driving unit 520 in the first direction y. Arranging the shielding component at the critical position between the light-emitting driving unit 520 and the voltage conversion unit 510 can shield the signal interference of the voltage conversion unit 510 on the light-emitting driving unit 520. For example, the shielding component is an in-board ground trace in the conductive layer of the circuit board.

[0176] In a usage scenario, the circuit board is placed vertically for use, and heat convection will occur in the up-and-down direction relative to the ground, that is, hot air rises and cold air descends. In this case, the components in the lower part will continuously bake the components in the upper part. For example, the driving structure near the edge of the substrate 600 in the first direction y is the first driving structure 501. Considering the influence of the upward heat transfer, among the three driving structures, the temperature of the components in the first driving structure 501 is often relatively higher. Based on this, when adjusting the layout of the components in each driving structure, first adjust the components in the first driving structure 501.

[0177] For example, the substrate 600 includes a first edge a1 and a second edge a2 arranged opposite to each other in the first direction y. In each driving structure, taking the first driving structure 501 as an example for illustration, the voltage conversion unit 510 and the light-emitting driving unit 520 are arranged in the direction from the first edge a1 to the second edge a2. At least in the voltage conversion unit 510 closest to the first edge a1 of the substrate 600, the inductor module 511 is arranged on the side of the voltage conversion unit 510 away from the light-emitting driving unit 520 in the first direction y. The power of the inductor module 511 is relatively large and the temperature is relatively high. Arranging the inductor module 511 at a relatively more marginal position on the substrate 600 is conducive to the heat dissipation of the inductor module 511. For example, the first edge a1 and the second edge a2 are parallel to the second direction x, and the third edge a3 is parallel to the first direction y. For example, the sizes of the first edge a1 and the second edge a2 are both smaller than the size of the third edge a3.

[0178] For example, taking the first driving structure 501 as an example for illustration, the output capacitor module 514 is arranged on the side of the voltage conversion unit 510 close to the light-emitting driving unit 520 in the first direction y. Arranging the output capacitor module 514 opposite to the inductor module 511 can reduce the influence of the heat generation of the inductor module 511 on the output capacitor module 514 and lower the temperature of the output capacitor module 514.

[0179] For example, taking the first driving structure 501 as an example for illustration, the diode module 513 is closer to the third edge a3 of the substrate 600 than the inductor module 511 and the output capacitor module 514, and the third edge a3 connects the first edge a1 and the second edge a2. Arranging the diode module 513 on the side close to the third edge a3 of the substrate 600 can increase the distance between the diode module 513 and other power devices, thereby reducing the influence of the heat generation of the power devices on the diode module 513.

[0180] For example, taking the first driving structure 501 as an example for illustration, the switching module 512 is arranged between the inductor module 511 and the output capacitor module 514. There is a relatively open area between the relatively arranged inductor module 511 and output capacitor module 514. By arranging the switching module 512 between the inductor module 511 and the output capacitor module 514, a relatively large distance can be maintained between the inductor module 511, the switching module 512, and the output capacitor module 514, improving the influence of heat generation addition between the modules.

[0181] For example, taking the first driving structure 501 as an example for illustration, the light-emitting unit driving circuit 500 further includes an input capacitor module 515, and the input capacitor module 515 is connected between the input terminal and the ground terminal. Considering that there is often a long wire between the input power supply for powering the voltage conversion unit 510 and the input terminal of the light-emitting unit driving circuit 500, the parasitic inductance on the wire may impede the change of current. Therefore, the input capacitor module 515 is provided at the input terminal of the light-emitting unit driving circuit 500. When the switching module 512 of the voltage conversion unit 510 is turned on, the current suddenly increases, and the input capacitor module 515 is in a discharging state to assist in providing current. When the switching module 512 is closed, the current suddenly decreases to 0, and the input capacitor module 515 is in a charging state. The input capacitor module 515 and the output capacitor module 514 are arranged opposite to each other in the second direction x to form a heat conduction channel extending along the first direction y, and the second direction x is parallel to the substrate 600 and intersects with the first direction y. For example, the second direction x is perpendicular to the first direction y. That is to say, the input capacitor module 515 and the output capacitor module 514 are arranged opposite to each other on both sides of the substrate 600, which can reduce the influence caused by the heat generation of the power device. Through the heat conduction channel formed between the input capacitor module 515 and the output capacitor module 514, heat can easily rise. It should be noted that Figure 15A A schematic diagram of the main board of the circuit board is schematically shown, and the arrangement manner of the components on the sub-board can be basically the same as that of the components on the main board. For example, the output capacitor module on the sub-board of the circuit board is correspondingly arranged on the side close to the output interface, the input capacitor module on the sub-board is correspondingly arranged on the side close to the input interface, and the arrangement manners of other components are exactly the same as those of the components on the main board.

[0182] For example, the multiple driving structures include a first driving structure, a second driving structure, and a third driving structure. At least two of the first driving structure, the second driving structure, and the third driving structure have non-overlapping portions in the first direction. Refer to Figure 15A, there is a non-overlapping portion between the first driving structure 501 and the second driving structure 502 in the first direction y, and the second driving structure 502 is arranged in a misaligned manner relative to the first driving structure 501 in the second direction x. In this way, a heat dissipation space is formed due to the misaligned arrangement of the first driving structure 501 and the second driving structure 502. In the usage state where the circuit board is placed vertically, the heat dissipated by the relatively lower second driving structure 502 can flow upward through this heat dissipation space, reducing the obstruction during heat circulation.

[0183] In some examples, the multiple driving structures include a first driving structure 501 and a second driving structure 502. The first driving structure 501 includes a first voltage conversion unit 5101 and a first light-emitting driving unit 5201, and the second driving structure 502 includes a second voltage conversion unit 5102 and a second light-emitting driving unit 5202; the first driving structure 501 and the second driving structure 502 are configured to satisfy at least one of the following conditions: the orthographic projection of the first voltage conversion unit 5101 on a plane perpendicular to the first direction y and the orthographic projection of the second voltage conversion unit 5102 on a plane perpendicular to the first direction y have a non-overlapping portion; the orthographic projection of the first light-emitting driving unit 5201 on a plane perpendicular to the first direction y and the orthographic projection of the second light-emitting driving unit 5202 on a plane perpendicular to the first direction y have a non-overlapping portion; the orthographic projection of the first voltage conversion unit 5101 on a plane perpendicular to the first direction y and the orthographic projection of the first light-emitting driving unit 5201 on a plane perpendicular to the first direction y have a non-overlapping portion; the orthographic projection of the first voltage conversion unit 5101 on a plane perpendicular to the first direction y and the orthographic projection of the second light-emitting driving unit 5202 on a plane perpendicular to the first direction y have a non-overlapping portion; the orthographic projection of the second voltage conversion unit 5102 on a plane perpendicular to the first direction y and the orthographic projection of the second light-emitting driving unit 5202 on a plane perpendicular to the first direction y have a non-overlapping portion; and the orthographic projection of the second voltage conversion unit 5102 on a plane perpendicular to the first direction y and the orthographic projection of the first light-emitting driving unit 5201 on a plane perpendicular to the first direction y have a non-overlapping portion.

[0184] For example, the orthographic projection of the first voltage conversion unit 5101 on a plane perpendicular to the first direction y and the orthographic projection of the second voltage conversion unit 5102 on a plane perpendicular to the first direction y have a non-overlapping portion. For example, among at least two of the first driving structure, the second driving structure, and the third driving structure, the voltage conversion units have non-overlapping portions in the first direction. For example, refer to Figure 15A, there is a non-overlapping portion between the voltage conversion unit 5101 in the first driving structure 501 and the voltage conversion unit 5102 in the second driving structure 502 in the first direction y, and the voltage conversion unit 5102 is misaligned with respect to the voltage conversion unit 5101 in the second direction x.

[0185] Reference Figure 15A , for example, the first voltage conversion unit 5101 includes a first diode module 513 and a first input capacitor module 515, and the second voltage conversion unit 5102 includes a second output capacitor module 514' and a second inductor module 511'. There is a first non-overlapping portion between the orthographic projection of the first diode module 513 on a plane perpendicular to the first direction y and the orthographic projection of the second output capacitor module 514' on a plane perpendicular to the first direction y; there is a second non-overlapping portion between the orthographic projection of the first input capacitor module 515 on a plane perpendicular to the first direction y and the orthographic projection of the second inductor module 511' on a plane perpendicular to the first direction y. For example, the size of the first non-overlapping portion in the second direction x is greater than 10 mm; the second direction x is parallel to the substrate and intersects the first direction y; the size of the second non-overlapping portion in the second direction x is greater than 3 mm.

[0186] Reference Figure 15A , for example, one side edge of the diode module 513 (the first diode module) close to the third edge a3 is one side edge of the first voltage conversion unit 5101, and one side edge of the input capacitor module 515 (the first input capacitor module) far from the third edge a3 is the other side edge of the first voltage conversion unit 5101. For example, one side edge of the output capacitor module 514' (the second output capacitor module) close to the third edge a3 is one side edge of the second voltage conversion unit 5102, and one side edge of the inductor module 511' (the second inductor module) far from the third edge a3 is the other side edge of the second voltage conversion unit 5102. Thus, the misalignment distance between the first diode module 513 and the second output capacitor module 514' is also the misalignment distance between the first voltage conversion unit 5101 and the second voltage conversion unit 5102 on the side close to the third edge a3. Correspondingly, the misalignment distance between the first input capacitor module 515 and the second inductor 511' is also the misalignment distance between the first voltage conversion unit 5101 and the second voltage conversion unit 5102 on the side far from the third edge a3.

[0187] Such as Figure 15AAs shown, taking the first driving structure 501 and the second driving structure 502 as examples, the two boundaries of the first voltage conversion unit 5101 in the first driving structure 501 in the second direction x are respectively the boundary of the first diode module 513 and the boundary of the first input capacitance module 515. The two boundaries of the first light-emitting driving unit 5201 in the first driving structure 501 in the second direction x are respectively the boundary of the first switching tube module 522 and the boundary of the first driving module 521. In the second driving structure 502, the two boundaries of the second voltage conversion unit 5102 in the second direction x are respectively the boundary of the second output capacitance module 514' and the boundary of the second inductor 511'. The two boundaries of the second light-emitting driving unit 5202 in the second driving structure 502 in the second direction x are respectively the boundary of the second switching tube module 522' and the boundary of the second driving module 521'. Thus, according to the misalignment distance between the components, the misalignment distance between the voltage conversion units and the misalignment distance between the light-emitting driving units can be obtained.

[0188] For example, the multiple driving structures include a first driving structure 501 and a second driving structure 502. The first driving structure 501 includes a first voltage conversion unit 5101, and the first voltage conversion unit 5101 includes a first inductor module 511. The second driving structure 502 includes a second voltage conversion unit 5102, and the second voltage conversion unit 5102 includes a second inductor module 511'. There is a non-overlapping part between the orthographic projection of the first inductor module 511 on the plane perpendicular to the first direction y and the orthographic projection of the second inductor module 511' on the plane perpendicular to the first direction y. For example, the inductor module 511 in the voltage conversion unit 5101 and the inductor module 511' in the voltage conversion unit 5102 are arranged in a staggered manner. For example, the switching module 512 in the voltage conversion module 5101 and the switching module 512' in the voltage conversion unit 5102 are arranged in a staggered manner.

[0189] For example, in at least two of the first driving structure, the second driving structure, and the third driving structure, the orthographic projection of the diode module on the plane perpendicular to the first direction is at least partially non-overlapping. For example, the diode module 513 in the voltage conversion module 5101 and the diode module 513' in the voltage conversion unit 5102 are arranged in a staggered manner.

[0190] For example, there is a non-overlapping part between the orthographic projection of the first light-emitting driving unit 5201 on the plane perpendicular to the first direction y and the orthographic projection of the second light-emitting driving unit 5202 on the plane perpendicular to the first direction y. For example, in at least two of the first driving structure, the second driving structure, and the third driving structure, there is a non-overlapping part of the light-emitting driving units in the first direction. For example, refer to Figure 15A, there is a non-overlapping part between the light-emitting driving unit 5201 in the first driving structure 501 and the light-emitting driving unit 5202 in the second driving structure 502 in the first direction y, and the light-emitting driving unit 5202 is misaligned with respect to the light-emitting driving unit 5201 in the second direction x.

[0191] For example, the first light-emitting driving unit 5201 includes a first switching tube module 522 and a first driving module 521, and the second light-emitting driving unit 5202 includes a second switching tube module 522' and a second driving module 521'; for example, there is a third non-overlapping part between the orthographic projection of the first switching tube module 522 on a plane perpendicular to the first direction y and the orthographic projection of the second switching tube module 522' on a plane perpendicular to the first direction y; there is a fourth non-overlapping part between the orthographic projection of the first driving module 521 on a plane perpendicular to the first direction y and the orthographic projection of the second driving module 521' on a plane perpendicular to the first direction y. For example, the size of the third non-overlapping part in the second direction x is greater than 5 mm; the size of the fourth non-overlapping part in the second direction x is greater than 3 mm. For example, the switching tubes 522 in the light-emitting driving unit 5201 and the switching tubes 522' in the light-emitting driving unit 5202 are misaligned. For example, in combination with the foregoing example, the switching tubes 522 are arranged in two rows and six columns, and the adjacent two rows of switching tubes 522 are misaligned. For example, the switching tubes 522' are also arranged in two rows and six columns, and the adjacent two rows of switching tubes 522' are misaligned.

[0192] For example, there is a non-overlapping part between the orthographic projection of the first voltage conversion unit 5101 on a plane perpendicular to the first direction y and the orthographic projection of the first light-emitting driving unit 5201 on a plane perpendicular to the first direction y. For example, there is a non-overlapping part between the orthographic projection of the first voltage conversion unit 5101 on a plane perpendicular to the first direction y and the orthographic projection of the second light-emitting driving unit 5202 on a plane perpendicular to the first direction y. For example, there is a non-overlapping part between the orthographic projection of the second voltage conversion unit 5102 on a plane perpendicular to the first direction y and the orthographic projection of the second light-emitting driving unit 5202 on a plane perpendicular to the first direction y. For example, there is a non-overlapping part between the orthographic projection of the second voltage conversion unit 5102 on a plane perpendicular to the first direction y and the orthographic projection of the first light-emitting driving unit 5201 on a plane perpendicular to the first direction y. For example, in at least two of the first driving structure, the second driving structure and the third driving structure, at least one voltage conversion unit and at least one light-emitting driving unit have a non-overlapping part in the first direction. For example, refer to Figure 15A, there is a non - overlapping part between the light - emitting driving unit 5201 in the first driving structure 501 and the voltage conversion unit 5102 in the second driving structure 502 in the first direction y, and the voltage conversion unit 5102 is misaligned with respect to the light - emitting driving unit 5201 in the second direction x. For example, the switching transistor 522 in the light - emitting driving unit 5201 is misaligned with the output capacitor module 514' in the voltage conversion unit 5102.

[0193] For example, the two boundaries of the first voltage conversion unit 5101 in the first driving structure 501 in the second direction x are respectively the boundary of the first diode module 513 and the boundary of the first input capacitor module 515. The two boundaries of the first light - emitting driving unit 5201 in the first driving structure 501 in the second direction x are respectively the boundary of the first switching transistor module 522 and the boundary of the first driving module 521. In the second driving structure 502, the two boundaries of the second voltage conversion unit 5102 in the second direction x are respectively the boundary of the second output capacitor module 514' and the boundary of the second inductor 511'. The two boundaries of the second light - emitting driving unit 5202 in the second direction x are respectively the boundary of the second switching transistor module 522' and the boundary of the second driving module 521'. It can be understood that the misalignment relationship between the voltage conversion unit and the light - emitting driving unit is also the distance difference between the edges of each component.

[0194] For example, there is a fifth non - overlapping part between the positive projection of the first diode module 513 on the plane perpendicular to the first direction y and the positive projection of the first switching transistor module 522 on the plane perpendicular to the first direction y. For example, the size of the fifth non - overlapping part in the second direction x is greater than 6 mm.

[0195] For example, there is a sixth non - overlapping part between the positive projection of the first input capacitor module 515 on the plane perpendicular to the first direction y and the positive projection of the first driving module 521 on the plane perpendicular to the first direction y. For example, the size of the sixth non - overlapping part in the second direction x is greater than 11 mm.

[0196] For example, there is a seventh non - overlapping part between the positive projection of the first diode module 513 on the plane perpendicular to the first direction y and the positive projection of the second switching transistor module 522' on the plane perpendicular to the first direction y; for example, the size of the seventh non - overlapping part in the second direction x is greater than 11 mm.

[0197] For example, there is an eighth non - overlapping part between the positive projection of the first input capacitor module 515 on the plane perpendicular to the first direction y and the positive projection of the second driving module 521' on the plane perpendicular to the first direction y; for example, the size of the eighth non - overlapping part in the second direction x is greater than 7 mm.

[0198] For example, there is a ninth non-overlapping portion between the positive projection of the first switching transistor module 522 on a plane perpendicular to the first direction y and the positive projection of the second output capacitor module 514' on a plane perpendicular to the first direction y; for example, the dimension of the ninth non-overlapping portion in the second direction x is greater than 5 mm.

[0199] For example, there is a tenth non-overlapping portion between the positive projection of the first driving module 521 on a plane perpendicular to the first direction y and the positive projection of the second inductor module 511' on a plane perpendicular to the first direction y; for example, the dimension of the tenth non-overlapping portion in the second direction x is greater than 8 mm.

[0200] For example, there is an eleventh non-overlapping portion between the positive projection of the second output capacitor module 514' on a plane perpendicular to the first direction y and the positive projection of the second switching transistor module 522' on a plane perpendicular to the first direction y; for example, the dimension of the eleventh non-overlapping portion in the second direction x is greater than 0.5 mm.

[0201] For example, there is a twelfth non-overlapping portion between the positive projection of the second inductor module 511' on a plane perpendicular to the first direction y and the positive projection of the second driving module 521' on a plane perpendicular to the first direction y; for example, the dimension of the twelfth non-overlapping portion in the second direction x is greater than 4 mm.

[0202] For example, the substrate includes a first edge and a second edge disposed opposite to each other in the first direction, and the heat conduction channel points from the second edge to the first edge. Refer to Figure 15D , for example, as shown by the arrow, the heat conduction channel can guide heat from the second edge a2 to the first edge a1.

[0203] As Figure 15D shown, the intervals between components form the heat conduction channel. Figure 15D Schematically shown in Figure 15D, in addition to the intervals extending in the first direction, there are also a plurality of intervals extending in the second direction on the circuit board of the present disclosure, such as the intervals between adjacent two diodes. In this way, in addition to the heat rising along the first direction, the heat can also be dissipated to both sides of the circuit board through the intervals in the second direction. In addition, by providing the intervals extending in the second direction, the distance between components can also be increased, thereby providing a larger peripheral space for the heat dissipation of components and reducing the problem of heat addition caused by the overly dense distribution of components.

[0204] Combined with Figures 15A to 15D As shown, for example, the first inductor module 511 includes a first inductor and a second inductor arranged oppositely in the second direction x, and the second inductor module 511' includes a third inductor and a fourth inductor arranged oppositely in the second direction x; the second direction x is parallel to the substrate and intersects with the first direction y; the heat conduction channel includes a first interval located between the first inductor and the second inductor. For example, the first interval is greater than or equal to 10 millimeters. Refer to Figure 15D , the gray area between the first inductor L1 and the second inductor L2 shows the first interval extending in the first direction y. It should be noted that in Figure 15D , only the embodiment in which the first interval extends to the second switch module 512' is shown. However, the present disclosure is not limited thereto. Refer to Figure 15A and Figure 15D , the first interval can also continue to extend along the first direction y to the second edge a2 of the substrate 600.

[0205] Combined with Figures 15A to 15D As shown, for example, the positive projection of the first interval on the plane perpendicular to the first direction y and the positive projection of the third inductor on the plane perpendicular to the first direction y have a first overlapping part 01. For example, the positive projection of the first interval on the plane perpendicular to the first direction y and the positive projection of the fourth inductor on the plane perpendicular to the first direction y have a second overlapping part. For example, the size of the first overlapping part 01 in the second direction x is greater than 1 / 3 of the size of the third inductor in the second direction x. For example, the size of the first overlapping part 01 in the second direction x can be 10 millimeters, and the size of the third inductor in the second direction x can be 17 millimeters. Of course, the sizes of the first overlapping part 01 and the third inductor are not limited herein. For example, the size of the second overlapping part in the second direction x is greater than 1 / 3 of the size of the fourth inductor in the second direction x. For example, the fourth inductor can also overlap with the interval in the first direction y. For example, the size of the second overlapping part in the second direction x can also be 10 millimeters, and the size of the fourth inductor in the second direction x can be 17 millimeters. Of course, the sizes of the second overlapping part and the fourth inductor are not limited herein.

[0206] Combined with Figures 15A to 15DAs shown, for example, the distance between the first inductor and the second inductor in the second direction x is the same as the distance between the third inductor and the fourth inductor in the second direction x. For example, the distance between the first inductor and the second inductor is equal to 10 millimeters, and the distance between the third inductor and the fourth inductor is equal to 10 millimeters. In some other examples, the distance between the first inductor and the second inductor may also be different from the distance between the third inductor and the fourth inductor, and the present disclosure does not limit this.

[0207] For example, the plurality of driving structures further includes a third driving structure 503. The third driving structure 503 includes a third voltage conversion unit 5103, and the third voltage conversion unit 5103 includes a third inductor module; there is a non-overlapping portion between the first inductor module and the third inductor module in the first direction. For example, there is a non-overlapping portion between the second inductor module and the third inductor module in the first direction. It can be understood that the inductor modules in the first driving structure 501, the second driving structure 502, and the third driving structure 503 can be misaligned pairwise.

[0208] For example, the third inductor module includes a fifth inductor and a sixth inductor arranged opposite to each other in the second direction. The distance between the first inductor and the third inductor in the first direction is the same as the distance between the third inductor and the fifth inductor in the first direction. The distance between the second inductor and the fourth inductor in the first direction is the same as the distance between the fourth inductor and the sixth inductor in the first direction. It can be understood that in adjacent two driving structures, the distance between inductor module and inductor module can be set to be the same. In this way, the distribution of each driving structure on the circuit board can be made more uniform.

[0209] Combined with Figures 15A to 15D As shown, for example, the second voltage conversion unit 5102 includes a second output capacitor module 514' and a second input capacitor module 515' arranged opposite to each other in the second direction x; the positive projection of the first interval on the plane perpendicular to the first direction y and the positive projection of the second input capacitor module 515' on the plane perpendicular to the first direction y have a third overlapping portion 03. Thus, in the first direction y, at least a part of the second input capacitor module 515' overlaps with the first interval, and the heat of the input capacitor module can be better dissipated from the first interval. For example, the size of the third overlapping portion 03 in the second direction x is greater than 1 / 3 of the size of the second input capacitor module 515' in the second direction x. For example, in the second direction x, the size of the third overlapping portion 03 is 10 millimeters, and the size of the second input capacitor module 515' is 18 millimeters. Of course, the sizes of the third overlapping portion 03 and the second input capacitor module 515' are not limited herein.

[0210] Combined with Figures 15A to 15DAs shown, for example, the first voltage conversion unit 5101 includes a first switch module 512; the positive projection of the first interval on a plane perpendicular to the first direction y at least partially overlaps with the positive projection of the first switch module 512 on a plane perpendicular to the first direction y. In this way, when the heat dissipated by the first switch module 512 travels upward, the first interval overlapping with the first switch module 512 in the first direction y can reduce the blockage of heat dissipation.

[0211] For example, the second voltage conversion unit 5102 includes a second switch module, and the distance between the first switch module and the first inductor module in the first direction is the same as the distance between the second switch module and the second inductor module in the first direction. For example, the plurality of driving structures further includes a third driving structure 503, and the third driving structure 503 includes a third voltage conversion unit 5103; the third voltage conversion unit 5103 includes a third switch module; the distance between the first switch module and the second switch module in the first direction is the same as the distance between the second switch module and the third switch module in the first direction. In this way, by setting the same distance between the switch modules in adjacent two driving structures, the distribution of components on the circuit board can be made more uniform.

[0212] Combined with Figures 15A to 15D As shown, for example, the first switch module 512 includes a first switching element and a second switching element arranged at intervals along the second direction x. The positive projection of the first interval on a plane perpendicular to the first direction y has a fourth overlapping portion 04 with the positive projection of the first switching element on a plane perpendicular to the first direction y, so as to facilitate the heat of the first switching element to travel upward through the first interval and dissipate. For example, the positive projection of the first interval on a plane perpendicular to the first direction y has a fifth overlapping portion with the positive projection of the second switching element on a plane perpendicular to the first direction y, so as to facilitate the heat of the second switching element to travel upward through the first interval and dissipate.

[0213] Combined with Figures 15A to 15D As shown, for example, the size of the first interval in the second direction x is greater than the size of the first switching element in the second direction x, so as to facilitate the heat dissipation of the first switching element. For example, the size of the first interval in the second direction x is greater than the size of the second switching element in the second direction x, so as to facilitate the heat dissipation of the second switching element.

[0214] Combined with Figures 15A to 15DAs shown, for example, the size of the fourth overlapping portion 04 in the second direction x is greater than 1 / 2 of the size of the first switching element in the second direction x. For example, the size of the fourth overlapping portion 04 in the second direction x is 5 mm, and the size of the first switching element in the second direction x is 8 mm. For example, the size of the fifth overlapping portion in the second direction x is greater than 1 / 2 of the size of the second switching element in the second direction x. For example, the size of the fifth overlapping portion in the second direction x is 5 mm, and the size of the second switching element in the second direction x is 8 mm. Of course, the present disclosure does not limit the sizes of the first switching element, the second switching element, the fourth overlapping portion 04, or the fifth overlapping portion.

[0215] Combined with Figures 15A to 15D As shown, for example, the second voltage conversion unit 5102 includes a second switching module 512'. The positive projection of the first interval on a plane perpendicular to the first direction y and the positive projection of the second switching module 512' on a plane perpendicular to the first direction y at least partially overlap. In some usage scenarios of the circuit board, the second voltage conversion unit 5102 is located below the first voltage conversion unit 5101, and the first interval in the first voltage conversion unit 5101 and the second switching module 512' in the second voltage conversion unit 5102 overlap in the first direction y, which can facilitate the heat dissipation of the second switching module 512' upward.

[0216] Combined with Figures 15A to 15D As shown, for example, the second switching module 512' includes a third switching element and a fourth switching element arranged at intervals along the second direction x. For example, the positive projection of the first interval on a plane perpendicular to the first direction y and the positive projection of the third switching element on a plane perpendicular to the first direction y at least partially overlap, so that the heat of the third switching element can dissipate from the first interval. For example, the positive projection of the first interval on a plane perpendicular to the first direction y and the positive projection of the fourth switching element on a plane perpendicular to the first direction y at least partially overlap, so that the heat of the fourth switching element can dissipate from the first interval.

[0217] Combined with Figures 15A to 15D As shown, for example, the positive projection of the first interval on a plane perpendicular to the first direction y completely overlaps with the positive projection of the third switching element on a plane perpendicular to the first direction y, thereby improving the heat dissipation effect on the third switching element. For example, the positive projection of the first interval on a plane perpendicular to the first direction y completely overlaps with the positive projection of the fourth switching element on a plane perpendicular to the first direction y, thereby improving the heat dissipation effect on the fourth switching element.

[0218] Combined with Figures 15A to 15DAs shown, for example, the voltage conversion unit includes an inductor module, an output capacitor module, and an input capacitor module. The input capacitor module and the output capacitor module are arranged opposite to each other in the second direction, and the second direction is parallel to the substrate and intersects with the first direction. The first inductor module 511 includes a first inductor and a second inductor arranged opposite to each other in the second direction x, and the second direction x is parallel to the substrate and intersects with the first direction y; the first voltage conversion unit 5101 includes a first output capacitor module 514 and a first input capacitor module 515 arranged opposite to each other in the second direction x; the heat conduction channel includes a second gap located between the first output capacitor module 514 and the first input capacitor module 515. For example, the second gap is greater than or equal to 28 millimeters. Refer to Figure 15D , the gray area between the first output capacitor module 514 and the first input capacitor module 515 shows the second gap extending along the first direction y. It should be noted that in Figure 15D , only the embodiment where the second gap extends to the second switch module 512' is shown. However, the present disclosure is not limited thereto. Refer to Figure 15A and Figure 15D , the second gap can also continue to extend along the first direction y to the second edge a2 of the substrate 600.

[0219] Combined with Figures 15A to 15D shown, for example, the positive projection of the second gap on the plane perpendicular to the first direction y and the positive projection of the first inductor on the plane perpendicular to the first direction y have a sixth overlapping part 06, so as to dissipate heat from the first inductor through the second gap. For example, the positive projection of the second gap on the plane perpendicular to the first direction y and the positive projection of the second inductor on the plane perpendicular to the first direction y have a seventh overlapping part 07, so as to dissipate heat from the second inductor through the second gap.

[0220] Combined with Figures 15A to 15D shown, for example, the size of the second gap in the second direction x is greater than the size of the first inductor in the second direction x, so as to improve the heat dissipation effect on the first inductor. For example, the size of the second gap in the second direction x is greater than the size of the second inductor in the second direction x, so as to improve the heat dissipation effect on the second inductor.

[0221] Combined with Figures 15A to 15D shown, for example, the size of the sixth overlapping part 06 in the second direction x is greater than 1 / 3 of the size of the first inductor in the second direction x. For example, the size of the sixth overlapping part 06 in the second direction x is 6 millimeters, and the size of the first inductor in the second direction x is 17 millimeters. For example, the size of the seventh overlapping part 07 in the second direction x is greater than 1 / 3 of the size of the second inductor in the second direction x. For example, the size of the seventh overlapping part 07 in the second direction x is 12 millimeters. The size of the second inductor in the second direction x is 19 millimeters.

[0222] Combined withFigures 15A to 15D As shown, for example, the positive projection of the second interval on a plane perpendicular to the first direction y and the positive projection of the second inductance module 511' on a plane perpendicular to the first direction y at least partially overlap, so that the heat of the second inductance module 511' can be dissipated through the second interval.

[0223] Combined with Figures 15A to 15D As shown, for example, the second inductance module 511' includes a third inductance and a fourth inductance arranged oppositely in the second direction x. The positive projection of the second interval on a plane perpendicular to the first direction y and the positive projection of the third inductance on a plane perpendicular to the first direction y at least partially overlap to improve the heat dissipation effect of the third inductance. The positive projection of the second interval on a plane perpendicular to the first direction y and the positive projection of the fourth inductance on a plane perpendicular to the first direction y at least partially overlap to improve the heat dissipation effect of the fourth inductance.

[0224] Combined with Figures 15A to 15D As shown, for example, the positive projection of the second interval on a plane perpendicular to the first direction y and the positive projection of the third inductance on a plane perpendicular to the first direction y completely overlap, that is, the positive projection of the second interval can completely cover the positive projection of the third inductance, increasing the heat dissipation area. For example, the positive projection of the second interval on a plane perpendicular to the first direction y and the positive projection of the fourth inductance on a plane perpendicular to the first direction y completely overlap, that is, the positive projection of the second interval can completely cover the positive projection of the fourth inductance, increasing the heat dissipation area.

[0225] Combined with Figures 15A to 15D As shown, for example, the second voltage conversion unit 5102 includes a second output capacitor module 514' and a second input capacitor module 515' arranged oppositely in the second direction x. The positive projection of the second interval on a plane perpendicular to the first direction y and the positive projection of the second output capacitor module 514' on a plane perpendicular to the first direction y have an eighth overlapping part 08 to improve the heat dissipation effect of the second output capacitor module 514'. For example, the positive projection of the second interval on a plane perpendicular to the first direction y and the positive projection of the second input capacitor module 515' on a plane perpendicular to the first direction y have a ninth overlapping part 09 to improve the heat dissipation effect of the second input capacitor module 515'.

[0226] Combined with Figures 15A to 15DAs shown, for example, the size of the eighth overlapping portion 08 in the second direction x is greater than 1 / 15 of the size of the second output capacitor module 514' in the second direction x. For example, in the second direction x, the size of the eighth overlapping portion 08 is 2 mm, and the size of the second output capacitor module 514' is 28 mm. For example, the size of the ninth overlapping portion 09 in the second direction x is greater than 2 / 3 of the size of the second output capacitor module 514' in the second direction x. For example, in the second direction x, the size of the ninth overlapping portion 09 is 22 mm, and the size of the second output capacitor module 514' is 28 mm. Of course, the sizes of the eighth overlapping portion 08, the ninth overlapping portion 09, the second output capacitor module 514', and the second input capacitor module 515' in the present disclosure are not limited.

[0227] Combined with Figures 15A to 15D As shown, for example, the first voltage conversion unit 5101 includes a first switch module 512. The positive projection of the second interval on a plane perpendicular to the first direction y overlaps at least partially with the positive projection of the first switch module 512 on a plane perpendicular to the first direction y, so that the heat of the first switch module 512 can be dissipated better.

[0228] Combined with Figures 15A to 15D As shown, for example, the first switch module 512 includes a first switch element and a second switch element arranged at intervals along the second direction x. For example, the positive projection of the second interval on a plane perpendicular to the first direction y overlaps at least partially with the positive projection of the first switch element on a plane perpendicular to the first direction y, so that the first switch element can be dissipated heat through the second interval. For example, the positive projection of the second interval on a plane perpendicular to the first direction y overlaps at least partially with the positive projection of the second switch element on a plane perpendicular to the first direction y, so that the second switch element can be dissipated heat through the second interval.

[0229] Combined with Figures 15A to 15D As shown, for example, the positive projection of the second interval on a plane perpendicular to the first direction y completely overlaps with the positive projection of the first switch element on a plane perpendicular to the first direction y to improve the heat dissipation effect on the first switch element. For example, the positive projection of the second interval on a plane perpendicular to the first direction y completely overlaps with the positive projection of the second switch element on a plane perpendicular to the first direction y to improve the heat dissipation effect on the second switch element.

[0230] Combined with Figures 15A to 15D As shown, for example, the second voltage conversion unit 5102 includes a second switch module 512'. The positive projection of the second interval on a plane perpendicular to the first direction y overlaps at least partially with the positive projection of the second switch module 512' on a plane perpendicular to the first direction y, so that the heat of the second switch module 512' can be dissipated better.

[0231] Combined Figures 15A to 15D As shown, for example, the second switch module 512' includes a third switch element and a fourth switch element arranged at intervals along the second direction x. For example, the positive projection of the second interval on the plane perpendicular to the first direction y and the positive projection of the third switch element on the plane perpendicular to the first direction y have a tenth overlapping portion 10, so that the heat of the third switch element can be dissipated better. For example, the positive projection of the second interval on the plane perpendicular to the first direction y and the positive projection of the fourth switch element on the plane perpendicular to the first direction y have an eleventh overlapping portion 11, so that the heat of the fourth switch element can be dissipated better.

[0232] Combined Figures 15A to 15D As shown, for example, the size of the tenth overlapping portion 10 in the second direction x is greater than 2 / 3 of the size of the third switch element in the second direction x. Of course, the tenth overlapping portion 10 can also completely overlap with the third switch element. For example, the size of the eleventh overlapping portion 11 in the second direction x is greater than 2 / 3 of the size of the fourth switch element in the second direction x. For example, the size of the eleventh overlapping portion 11 in the second direction x is 7 mm, and the size of the fourth switch element in the second direction x is 8 mm. It can be understood that the present disclosure does not limit the sizes of the tenth overlapping portion 10, the eleventh overlapping portion 11, the third switch element, and the fourth switch element. Combined Figures 15A to 15D As shown, for example, the heat conduction channel includes a second interval located between the output capacitor module and the input capacitor module. For example, the second interval in the first driving structure 501 is formed between the input capacitor module 515 and the output capacitor module 514, for example, between the input capacitor module 515, the first output capacitor C1, and the second output capacitor C2. The second interval in the second driving structure 502 is formed between the input capacitor module 515' and the output capacitor module 514', for example, between the input capacitor module 515', the first output capacitor C1', and the second output capacitor C2'. The second interval in the third driving structure 503 is formed between the input capacitor module 515'' and the output capacitor module 514'', for example, between the input capacitor module 515'', the first output capacitor C1'', and the second output capacitor C2''.

[0233] Combined Figures 15A to 15DAs shown, for example, the second intervals in the first driving structure 501, the second intervals in the second driving structure 502, and the second intervals in the third driving structure 503 have overlapping portions in the corresponding extending directions. In this way, when the components closer to the second edge a2 dissipate heat, since the heat rises, the heat below can sequentially pass through the three second intervals and dissipate from one end of the second interval close to the first edge a1. Thus, the heat conduction channels in the driving structure can reduce the resistance during the upward heat transfer process and improve the heat dissipation efficiency of the components. For example, the size of the second interval in the second driving structure 502 in the second direction and the size of the second interval in the third driving structure 503 in the second direction are both smaller than the size of the second interval in the first driving structure 501 in the second direction. Since the components above are continuously baked by the heat source below, the wider second interval can not only increase the distance between the output capacitor module 514 and the input capacitor module 515, but also make the heat dissipate more easily.

[0234] For example, the orthographic projection of the inductor module on a plane perpendicular to the first direction intersects with the orthographic projection of the interval on a plane perpendicular to the first direction. For example, referring to Figure 15D , in the first driving structure 501, a partial structure of the inductor module 511 is located in the extending direction of the interval. Taking the first driving structure 501 as an example for illustration, the inductor module 511 includes a first inductor L1 and a second inductor L2 connected in parallel, and the first inductor L1 and the second inductor L2 are spaced apart from each other along the second direction x. The spaced-apart first inductor L1 and second inductor L2 can increase the distance between the components to improve the heat dissipation effect. For example, a partial structure of the first inductor L1 is located in the extending direction of the second interval, and a partial structure of the second inductor L2 is located in the extending direction of the second interval.

[0235] For example, the ratio of the size of the interval in the second direction to the size of the first inductor in the second direction is greater than 1.5. For example, the ratio of the size of the interval in the second direction to the size of the second inductor in the second direction is greater than 1.5, and this ratio can be but is not limited to 1.5, 1.55, 1.6, 1.65, 1.7, etc., and the present disclosure does not limit this. Referring to Figure 15D , in the first driving structure 501, the ratio of the second interval to the length dimension of the first inductor L1 is greater than 1.5. The ratio of the second interval to the length dimension of the second inductor L2 is greater than 1.5, and this ratio can be but is not limited to 1.5, 1.55, 1.6, 1.65, 1.7, etc., and the present disclosure does not limit this.

[0236] For example, the orthographic projection of the interval on a plane perpendicular to the second direction and the orthographic projection of the inductor module on a plane perpendicular to the second direction are at least partially non-overlapping. For example, referring to Figure 15D, taking the first driving structure 501 as an example for illustration. Since the second interval is located between the output capacitance module 514 and the input capacitance module 515, and the second interval is spaced from the inductance module 511 in the first direction y, that is, the inductance module 514 is spaced from the output capacitance module 514, and the inductance module 514 is spaced from the input capacitance module 515, which increases the spacing between components and improves the heat generation effect between components.

[0237] Combined with Figures 15A to 15D shown, for example, the first inductance module 511 includes a first inductor and a second inductor arranged opposite to each other in the second direction x, the second direction x is parallel to the substrate and intersects with the first direction y; the first voltage conversion unit 5101 includes a first switch module 512, and the first switch module 512 includes a first switch element and a second switch element arranged at intervals in the second direction x. The heat conduction channel includes a third interval located between the first switch element and the second switch element. Refer to Figure 15D , the gray area between the first switch element Q1 and the second switch element Q2 shows the third interval extending in the first direction y. It should be noted that in Figure 15D , only the embodiment where the third interval extends to the second switch module 512' is shown. However, the present disclosure is not limited to this. Refer to Figure 15A and Figure 15D , the third interval can also continue to extend along the first direction y to the second edge a2 of the substrate 600. For example, the third interval is greater than or equal to 8 mm. For example, the positive projection of the third interval on the plane perpendicular to the first direction y and the positive projection of the first inductor on the plane perpendicular to the first direction y have a twelfth overlapping part 12, so as to dissipate heat from the first inductor through the third interval. For example, the positive projection of the third interval on the plane perpendicular to the first direction y and the positive projection of the second inductor on the plane perpendicular to the first direction y have a thirteenth overlapping part 13, so as to dissipate heat from the second inductor through the third interval.

[0238] Combined with Figures 15A to 15D shown, for example, the size of the twelfth overlapping part 12 in the second direction x is greater than 1 / 10 of the size of the first inductor in the second direction x. For example, the size of the thirteenth overlapping part 13 in the second direction x is greater than 1 / 10 of the size of the second inductor in the second direction x. For example, the size of the thirteenth overlapping part 13 in the second direction x is 3 mm, and the size of the second inductor in the second direction x is 19 mm. Of course, the present disclosure does not limit the sizes of the twelfth overlapping part 12, the thirteenth overlapping part 13, the first inductor, and the second inductor.

[0239] Combined with Figures 15A to 15DAs shown, for example, the second inductance module 511' includes a third inductance and a fourth inductance arranged oppositely in the second direction x; the second direction x is parallel to the substrate and intersects the first direction y. For example, the positive projection of the third interval on the plane perpendicular to the first direction y and the positive projection of the third inductance on the plane perpendicular to the first direction y have a fourteenth overlapping part 14 to dissipate heat from the third inductance through the third interval. For example, the positive projection of the third interval on the plane perpendicular to the first direction y and the positive projection of the fourth inductance on the plane perpendicular to the first direction y have a fifteenth overlapping part to dissipate heat from the fourth inductance through the third interval.

[0240] Combined with Figures 15A to 15D As shown, for example, the dimension of the fourteenth overlapping part 14 in the second direction x is greater than 1 / 2 of the dimension of the third inductance in the second direction x. For example, the dimension of the fourteenth overlapping part 14 in the second direction x is 8 mm, and the dimension of the third inductance in the second direction x is 17 mm. For example, the dimension of the fifteenth overlapping part in the second direction x is greater than 1 / 2 of the dimension of the fourth inductance in the second direction x. Of course, the present disclosure does not limit the dimensions of the fourteenth overlapping part 14, the fifteenth overlapping part, the third inductance, and the fourth inductance.

[0241] Combined with Figures 15A to 15D As shown, for example, the second voltage conversion unit 5102 includes a second output capacitance module 514' and a second input capacitance module 515' arranged oppositely in the second direction x. For example, the positive projection of the third interval on the plane perpendicular to the first direction y and the positive projection of the second output capacitance module 514' on the plane perpendicular to the first direction y have a sixteenth overlapping part to dissipate heat from the second output capacitance module 514' through the third interval. For example, the positive projection of the third interval on the plane perpendicular to the first direction y and the positive projection of the second input capacitance module 515' on the plane perpendicular to the first direction y have a seventeenth overlapping part 17 to dissipate heat from the second input capacitance module 515' through the third interval.

[0242] Combined with Figures 15A to 15D As shown, for example, the dimension of the sixteenth overlapping part in the second direction x is greater than 1 / 3 of the dimension of the second output capacitance module 514' in the second direction x. For example, the dimension of the seventeenth overlapping part 17 in the second direction x is greater than 1 / 3 of the dimension of the second input capacitance module 515' in the second direction x. For example, the dimension of the seventeenth overlapping part 17 in the second direction x is 8 mm, and the dimension of the second input capacitance module 515' in the second direction x is 28 mm. Of course, the present disclosure does not limit the dimensions of the sixteenth overlapping part, the seventeenth overlapping part 17, the second output capacitance module 514', and the second input capacitance module 515'.

[0243] Combined withFigures 15A to 15D As shown, for example, the second voltage conversion unit 5102 includes a second switch module 512'; the positive projection of the third interval on a plane perpendicular to the first direction y at least partially overlaps with the positive projection of the second switch module 512' on a plane perpendicular to the first direction y, so as to dissipate heat from the second switch module 512' through the third interval.

[0244] Combined with Figures 15A to 15D As shown, for example, the second switch module 512' includes a third switch element and a fourth switch element arranged at intervals along the second direction x; the positive projection of the third interval on a plane perpendicular to the first direction y has an eighteenth overlapping part 18 with the positive projection of the third switch element on a plane perpendicular to the first direction y, so as to dissipate heat from the third switch element through the third interval. For example, the positive projection of the third interval on a plane perpendicular to the first direction y has a nineteenth overlapping part with the positive projection of the fourth switch element on a plane perpendicular to the first direction y, so as to dissipate heat from the fourth switch element through the third interval.

[0245] Combined with Figures 15A to 15D As shown, for example, the size of the eighteenth overlapping part 18 in the second direction x is greater than 1 / 3 of the size of the third switch element in the second direction x. For example, the size of the eighteenth overlapping part 18 in the second direction x is 3 mm, and the size of the third switch element in the second direction x is 7 mm. The size of the nineteenth overlapping part in the second direction x is greater than 1 / 3 of the size of the fourth switch element in the second direction x. Of course, the present disclosure does not limit the sizes of the eighteenth overlapping part 18, the nineteenth overlapping part, the third switch element, and the fourth switch element.

[0246] For example, the voltage conversion unit further includes a switch module. For example, the positive projection of the switch module on a plane perpendicular to the first direction intersects with the positive projection of the heat conduction channel on a plane perpendicular to the first direction. For example, referring to Figure 15D , in the first driving structure 501, a partial structure of the switch module 512 is located in the extending direction of the heat conduction channel. Taking the first driving structure 501 as an example, a partial structure of the first switch element Q1 is located in the extending direction of the heat conduction channel, and a partial structure of the second switch element Q2 is located in the extending direction of the heat conduction channel.

[0247] Combined with Figures 15A to 15DAs shown, for example, the first inductance module 511 includes a first inductor and a second inductor arranged opposite to each other in the second direction x, where the second direction x is parallel to the substrate and intersects with the first direction y; the first voltage conversion unit 5101 includes a first diode module 513, and the first diode module 513 includes a first diode and a second diode spaced apart in the first direction y; the first voltage conversion unit 5101 further includes a first output capacitor module 514. The heat conduction channel includes a fourth gap located between the first diode and the second inductor. Refer to Figure 15A and Figure 15D , the gray area between the first diode D1 and the second inductor L2 shows a fourth gap extending along the first direction y. It should be noted that in Figure 15D , only the embodiment where the fourth gap extends to the second output capacitor module 514' is shown. However, the present disclosure is not limited thereto. Refer to Figure 15A and Figure 15D , the fourth gap can also continue to extend along the first direction y to the second edge a2 of the substrate 600. For example, the fourth gap is greater than or equal to 12 mm. For example, the positive projection of the fourth gap on a plane perpendicular to the first direction y and the positive projection of the first output capacitor module 514 on a plane perpendicular to the first direction y have a twentieth overlapping portion 20, so as to dissipate heat from the first output capacitor module 514 through the fourth gap.

[0248] Combined with Figures 15A to 15D as shown, for example, the size of the twentieth overlapping portion 20 in the second direction x is greater than 1 / 3 of the size of the first output capacitor module 514 in the second direction x. For example, the size of the twentieth overlapping portion 20 in the second direction x is 12 mm, and the size of the first output capacitor module 514 in the second direction x is 28 mm. Of course, the present disclosure does not limit the sizes of the twentieth overlapping portion 20 and the first output capacitor module 514.

[0249] Combined with Figures 15A to 15D as shown, for example, the second voltage conversion unit 5102 includes a second output capacitor module 514'; the positive projection of the fourth gap on a plane perpendicular to the first direction y and the positive projection of the second output capacitor module 514' on a plane perpendicular to the first direction y have a twenty - first overlapping portion 21 to dissipate heat from the second output capacitor module 514' through the fourth gap.

[0250] Combined with Figures 15A to 15DAs shown, for example, the size of the twenty-first overlapping portion 21 in the second direction x is greater than 1 / 3 of the size of the second output capacitor module 514' in the second direction x. For example, the size of the twenty-first overlapping portion 21 in the second direction x is 12 mm, and the size of the second output capacitor module 514' in the second direction x is 28 mm. Of course, the present disclosure does not limit the sizes of the twenty-first overlapping portion 21 and the second output capacitor module 514'.

[0251] Combined with Figures 15A to 15D As shown, for example, the plurality of driving structures include a first driving structure 501 and a second driving structure 502. The first driving structure 501 includes a first voltage conversion unit 5101, and the first voltage conversion unit 5101 includes a first diode module 513. The second driving structure 502 includes a second voltage conversion unit 5102, and the second voltage conversion unit 5102 includes a second diode module 513'. The orthographic projection of the first diode module 513 on a plane perpendicular to the first direction y and the orthographic projection of the second diode module 513' on a plane perpendicular to the first direction y have a non-overlapping portion. In this way, through the dislocation between the first diode module 513 and the second diode module 513', the blockage of heat dissipation between components in the first direction y can be reduced, thereby improving the heat dissipation effect.

[0252] Combined with Figures 15A to 15D As shown, for example, the orthographic projection of the first diode module 513 on a plane perpendicular to the first direction y and the orthographic projection of the second diode module 513' on a plane perpendicular to the first direction y do not overlap at all. In this way, the first diode module 513 and the second diode module 513' are completely dislocated, thereby providing a larger heat dissipation space.

[0253] For example, in at least two of the first driving structure, the second driving structure, and the third driving structure, the distance between the inductor module and the switch module in the first direction is the same. For example, in at least two of the plurality of driving structures, the distance between the inductor module and the switch module in the first direction is the same. For example, referring to Figure 15D , in the second driving structure 502 and the third driving structure 503, the distance between the inductor module and the switch module is the same. For example, the distance l21 between the first inductor L1' and the first switching element Q1' and the distance l31 between the first inductor L1'' and the first switching element Q1'' can be the same or different. For example, in the first driving structure, the second driving structure, and the third driving structure, the distances between the inductor module and the switch module can all be the same or all be different. In Figure 15DIn the example, the distance l11 between the first inductor L1 and the first switching element Q1 is different from the distance l21 and is also different from the distance l31. For example, the distance l22 between the second inductor L2' and the second switching element Q2' may be the same as or different from the distance l32 between the second inductor L2'' and the second switching element Q2''. For example, the distance l12 between the second inductor L2 and the second switching element Q2 is different from the distance l22 and is also different from the distance l32.

[0254] Reference Figure 15A and Figure 15B , for example, the substrate 600 includes a first conductive layer 610 and a first solder mask layer 620. The first conductive layer 610 and the first solder mask layer 620 are located on the side of the substrate 600 where the light-emitting unit driving circuit 500 is provided. The first conductive layer 610 is located on the side of the first solder mask layer 620 away from the light-emitting unit driving circuit 500. A first opening 621 exposing the first conductive layer 610 is formed in the first solder mask layer 620. The first conductive layer 610 can be exposed through the first opening 621 formed in the first solder mask layer 620, thereby dissipating heat. Considering the layout of the traces and components on the circuit board, there are slight differences in the first opening 621 in the regions where the first driving structure 501, the second driving structure 502, and the third driving structure 503 are located. In the present disclosure, the first opening 621 in the region where the first driving structure 501 is located is taken as an example for illustration.

[0255] The first opening 621 includes a first opening portion 6211 which is located between the inductor module 511, the diode module 513, and the switch module 512, thereby dissipating heat from the middle position of the components and improving the additive heating effect between the components. The area of the first opening portion 6211 is greater than or equal to 970 square millimeters.

[0256] The first opening 621 includes a second opening portion 6212 which surrounds the inductor module 511, thereby dissipating heat from the inductor module 511. The area of the second opening portion 6212 is greater than or equal to 320 square millimeters. Surrounding means that the second opening portion 6212 is formed in the peripheral region of the inductor module 511. The surrounding can be, for example, Figure 15A as shown, only surrounding a partial circumferential region of the inductor module 511, or can be adjusted to surround the entire circumferential region of the inductor module according to actual needs. The present disclosure does not limit this here.

[0257] The first opening 621 includes a third opening portion 6213 which surrounds the diode module 513, thereby dissipating heat from the diode module 513. It can be understood that the third opening portion 6213 can be, for example, Figure 15AThe opening shown is provided between the first diode D1 and the second diode D2, and can also enclose all regions circumferentially of the diode module according to actual needs. The third opening 6213 includes a sub-region located between the first diode D1 and the second diode D2, with an area greater than or equal to 50 square millimeters. The third opening 6213 also includes a region located on the side of the second diode D2 away from the first diode D1, with an area greater than or equal to 90 square millimeters.

[0258] Reference Figures 15A to 15C , the substrate 600 includes a second conductive layer 630 and a second solder mask layer 640 on the side of the first conductive layer 610 away from the first solder mask layer 620, and the second conductive layer 630 is located between the second solder mask layer 640 and the first conductive layer 610. A second opening 641 exposing the second conductive layer 630 is formed in the second solder mask layer 640, and the orthographic projection of the second opening 641 on the third reference plane overlaps with the orthographic projection of the first opening 621 on this plane, and the third reference plane is parallel to the substrate 600. In this way, the openings on the opposite sides of the substrate 600 correspond to each other. While the components dissipate heat through the first opening 621, the side where the second opening 641 is located dissipates heat through the second opening 641, improving the heat dissipation efficiency of the circuit board. As Figure 15B , the second opening 641 includes a first opening portion 6411 corresponding to the first opening portion 6211 of the first opening 621, a second opening portion 6412 corresponding to the second opening portion 6212 of the first opening 621, and a third opening portion 6413 corresponding to the third opening portion 6213 of the first opening 621. The second opening 641 also includes a fourth opening portion 6414 corresponding to the position where the diode module 513 is located. As Figure 15A and Figure 15B shown, the orthographic projection of the second opening 641 on the third reference plane covers the orthographic projection of the first opening 621 on this surface. For example, the orthographic projection of the first opening 621 on the substrate 600 completely falls within the orthographic projection of the second opening 641 on the substrate 600. It can be understood that the shape and size of the second opening can also be adjusted according to actual needs, Figure 15B only the second opening 641 is schematically shown, and the shape and size of the second opening are not limited.

[0259] For example, it further includes a plurality of vias that at least penetrate the first conductive layer 610 and the second conductive layer 630, and the plurality of vias are arranged in an array. For example, the vias are heat dissipation vias. The vias can conduct the heat of the first conductive layer 610 to the second conductive layer 630, thereby dissipating heat. For example, the vias are filled with electroplated copper. The positive projection of the first opening 621 on the third reference plane (a plane parallel to the substrate 600) covers at least part of the positive projection of the vias on the third reference plane, that is, the vias are opened around the components, so as to dissipate heat faster. For example, the positive projection of the vias on the plane parallel to the substrate 600 also falls into the positive projection of the second opening 641 on this plane. In this way, the vias can conduct the heat at the first opening 621 to the second opening 641.

[0260] Figure 17A Schematic diagram of a circuit board provided by another example of the present disclosure. Figure 17B is Figure 17A Partial schematic diagram of the circuit board shown, Figure 17A and Figure 15A The difference from Figure 17A is that the number of switching elements and the number of output capacitors in each voltage conversion unit of Figure 15A are different from the number of switching elements and the number of output capacitors in each voltage conversion unit of Figure 17A For example, each voltage conversion unit in Figure 17A includes three switching elements and one output capacitor. Of course, Figure 1 There may be other differences between the circuit board shown in Figure 17C is Figure 17A Planar schematic diagram of the circuit board shown. Figure 18 Schematic diagram of a light-emitting unit driving circuit provided by another example of the present disclosure. It should be noted that, in order to more clearly show the arrangement of the components in the circuit board, Figure 17B only part of the components in the first driving structure are schematically shown, Figure 17C only part of the components on the circuit board are schematically shown.

[0261] For example, as shown in Figures 17A to 17C and in combination with Figure 15D, the circuit board includes a substrate 600, a plurality of voltage conversion units 510 and a plurality of light-emitting driving units 520 disposed on the substrate 600. The voltage conversion unit 510 includes an input end and an output end, and is configured to output a preset voltage. The light-emitting driving unit 520 is connected to the output end of the voltage conversion unit 510 and is configured to drive the light-emitting unit. The plurality of voltage conversion units 510 and the plurality of light-emitting driving units 520 are arranged in one-to-one correspondence, and a voltage conversion unit 510 is disposed between adjacent light-emitting driving units 520. The voltage conversion unit 510 includes a first inductor L1 and a second inductor L2 connected in parallel, and the first inductor L1 and the second inductor L2 are arranged in a staggered manner. For the circuit board provided by the present disclosure, by disposing the voltage conversion unit 510 between adjacent light-emitting driving units 520 and arranging the first inductor L1 and the second inductor L2 in the voltage conversion unit 510 in a staggered manner, heat-generating components can be dispersed, and the influence of heat addition between components can be improved.

[0262] For example, as Figures 17A to 17C shown, and in combination with Figure 15D , the circuit board includes a first edge a1 close to the voltage conversion unit 510 in the first direction y, and the first direction y is the direction from the voltage conversion unit 510 to the light-emitting driving unit 520; the distance between the first inductor L1 and the first edge a1 in the first direction y is a first distance, and the distance between the second inductor L2 and the first edge a1 in the first direction y is a second distance, and the first distance is different from the second distance. By setting the first distance and the second distance to be different, a larger staggered space between the first inductor L1 and the second inductor L2 can be obtained, improving the heat dissipation effect.

[0263] For example, as Figures 17A to 17C shown, and in combination with Figure 15D , the difference between the first distance and the second distance is less than or equal to 1 / 2 of the width dimension of the first inductor L1 in the first direction y. For example, the difference between d54 and d55 is less than or equal to 1 / 2 of the width dimension of the first inductor L1 in the first direction y.

[0264] For example, as Figures 17A to 17C shown, and in combination with Figure 15D, a plurality of voltage conversion units 510 include a first voltage conversion unit 510 and a second voltage conversion unit 510 located on both sides of the first light-emitting driving unit 520 in the first direction y, where the first direction y is the direction pointing from the voltage conversion unit 510 to the light-emitting driving unit 520; the first voltage conversion unit 510 includes a first inductor module 511, and the second voltage conversion unit 510 includes a second inductor module 511'; the distance between the first inductor module 511 and the second inductor module 511' in the first direction y is y, there is a non-overlapping part between the orthographic projection of the first inductor L1 on the first reference plane and the orthographic projection of the second inductor L2 on the first reference plane, the size of the non-overlapping part in the first direction y is h, and the size of the light-emitting driving unit 520 in the first direction y is x, then: y = a×x + b×h, 2 < a < 4, 1 < b < 3; where the second direction x intersects the first direction y, and the first reference plane is a plane perpendicular to the second direction x. For example, by setting the parameter relationship between the distance between the first inductor module 511 and the second inductor module 511' and the misalignment size between the first inductor L1 and the second inductor L2, the layout of each component on the circuit board can be made more reasonable, and the heat dissipation effect can also be improved.

[0265] For example, as Figures 17A to 17C shown, and in combination with Figure 15D , a plurality of voltage conversion units 510 include a first voltage conversion unit 510 and a second voltage conversion unit 510 located on both sides of the first light-emitting driving unit 520. The first voltage conversion unit 510 includes a first inductor module 511, a first capacitor module, and a first switch module 512, and the second voltage conversion unit 510 includes a second inductor module 511'; the distance between the first inductor module 511 and the second inductor module 511' in the first direction y is y, the size of the first inductor module 511 in the first direction y is y1, the size of the first capacitor module in the first direction y is y2, and the size of the first switch module 512 in the first direction y is y3, then: y = k×y1 + y3 + 2×y2, 1 < k < 3; where the first direction y is the direction pointing from the voltage conversion unit 510 to the light-emitting driving unit 520. By setting the parameter relationship between the first inductor module 511, the first capacitor module, the first switch module 512, and the distance y between the first inductor module 511 and the second inductor module 511' in the first direction y, the arrangement between each driving structure can be made more reasonable.

[0266] For example, as Figures 17A to 17C shown, and in combination with Figure 15D, a plurality of voltage conversion units 510 include a first voltage conversion unit 510 and a second voltage conversion unit 510 located on both sides of the first light-emitting driving unit 520. The first voltage conversion unit 510 includes a first inductor module 511, a first capacitor module, and a first switch module 512. The first inductor module 511 includes a first inductor L1 and a second inductor L2 connected in parallel with each other. The first inductor L1 and the second inductor L2 have a first interval in the second direction x. The first capacitor module includes a first output capacitor module 514 and a first input capacitor module 515 connected in parallel with each other. The first output capacitor module 514 and the first input capacitor module 515 have a second interval in the second direction x. The first switch module 512 includes a first switch Q1 and a second switch Q2 connected in parallel with each other. The first switch Q1 and the second switch Q2 have a third interval in the second direction x. The second voltage conversion unit 510 includes a second capacitor module. The second capacitor module includes a second output capacitor module 514' and a second input capacitor module 515' connected in parallel with each other. The second output capacitor module 514' and the second input capacitor module 515' have a fourth interval in the second direction x. The fourth interval and at least one of the first interval, the second interval, and the third interval have an overlapping part on the second reference plane. The second reference plane is a plane perpendicular to the first direction y. The first direction y is the direction from the voltage conversion unit 510 to the light-emitting driving unit 520. The second direction x is parallel to the substrate 600 and intersects with the first direction y.

[0267] For example, as Figures 17A to 17C shown, and combined with Figure 15D , the first interval, the second interval, the third interval, and the fourth interval have a common overlapping part on the second reference plane. By setting the first interval, the second interval, the third interval, and the fourth interval to overlap, the obstruction suffered by the heat of the components on the circuit board when dissipating upward can be reduced, and the heat dissipation efficiency can be improved.

[0268] For example, as Figures 17A to 17C shown, and combined with Figure 15D , the size of the common overlapping part in the second direction x is less than or equal to the size of the first interval in the second direction x. For example, the ratio of the size of the common overlapping part in the second direction x to the size of the first interval in the second direction x is 0.3 to 0.7. For example, the ratio of the size of the common overlapping part in the second direction x to the size of the first interval in the second direction x is 0.4 to 0.6. For example, the ratio of the size of the common overlapping part in the second direction x to the size of the first interval in the second direction x is 0.5.

[0269] For example, as Figures 17A to 17C shown, and combined with Figure 15D, the first interval, the second interval, the third interval, and the fourth interval are configured to satisfy at least one of the following conditions: the first interval is greater than or equal to 10 millimeters; the second interval is greater than or equal to 28 millimeters; the third interval is greater than or equal to 8 millimeters; the fourth interval is greater than or equal to 4 millimeters.

[0270] In some embodiments, as Figure 17A shown and in combination with Figure 17B , taking the voltage conversion unit 5101 in the first driving structure 501 as an example for illustration. Combining with some of the foregoing embodiments, in order to further reduce the temperature of the switching module 512, as Figure 18 shown, the switching module 512 includes a first switching element Q1, a second switching element Q2, and a third switching element Q3 connected in parallel. Referring to Figure 17A and Figure 17B , the first switching element Q1, the second switching element Q2, and the third switching element Q3 are arranged at intervals along the second direction x, and the distance d51 between any two of them is not less than 8 millimeters.

[0271] Referring to Figure 17A and Figure 17B , for example, according to the temperature conditions of the inductor module 511, the switching module 512, and the diode module 513, the distance d51 between any two of the first switching element Q1, the second switching element Q2, and the third switching element Q3 in the switching module 512 is less than the distance d52 between the first diode D1 and the second diode D2 in the diode module 513, and the distance d52 between the first diode D1 and the second diode D2 is less than the distance d53 between the first inductor L1 and the second inductor L2 in the inductor module 511.

[0272] Referring to Figure 17A and Figure 17B , for example, the inductor module 511 is located on one side of the switching module 512 in the first direction y, and the first inductor L1 and the second inductor L2 are arranged at intervals along the second direction x. For example, the distance d53 between the first inductor L1 and the second inductor L2 is greater than or equal to 10 millimeters.

[0273] Referring to Figure 17A and Figure 17B, for example, in the first direction y, the minimum distance between the first inductor L1 and the outer periphery of the substrate 600 facing each other is the first distance d54, and the minimum distance between the second inductor L2 and the outer periphery of the substrate 600 facing each other is the second distance d55. The first distance d54 is different from the second distance d55. For example, the minimum distance between one side edge of the first inductor L1 in the first direction y and the outer periphery of the substrate 600 is the first distance d54, and the minimum distance between one side edge of the second inductor L2 in the first direction y and the outer periphery of the substrate 600 is the second distance d55. The first distance d54 is different from the second distance d55. The first inductor L1 and the second inductor L2 are arranged staggeredly in the first direction y, which can increase the peripheral space of the first inductor L1 and the second inductor L2, thereby increasing the heat dissipation space of the first inductor L1 and the second inductor L2 and reducing the temperature of the inductor module 511.

[0274] Reference Figure 17A and Figure 17B , for example, the difference between the first distance d54 and the second distance d55 is greater than or equal to 1 / 2 of the width dimension of the first inductor L1 in the first direction y. For example, the staggering distance between the first inductor L1 and the second inductor L2 in the first direction y is greater than or equal to 1 / 2 times the width dimension of the first inductor L1. For example, the size specifications of the first inductor L1 and the second inductor L2 are the same. Reference Figure 17C , for example, the difference between the first distance d54 and the second distance d55 is also the staggering distance between the first inductor L1 and the second inductor L2 in the first direction y. For example, among multiple driving structures, the staggering distance between the first inductor and the second inductor in the first direction y can be the same or different. Reference Figure 17C , at least two of the staggering distance d between the first inductor L1 and the second inductor L2, the staggering distance d' between the first inductor L1' and the second inductor L2', and the staggering distance d'' between the first inductor L1'' and the second inductor L2'' are the same.

[0275] Reference Figure 17A and Figure 17B , for example, the first inductor L1 and the second inductor L2 are arranged staggeredly in the first direction y. For example, between the inductor module 511 and the switch module 512, the minimum distance d56 between the first inductor L1, which is relatively closer to the switch module 512, and the first switching element Q1 is 10 millimeters at least, that is, greater than or equal to 10 millimeters. For example, the distance d57 between the second inductor L2, which is relatively farther from the switch module 512, and the third switching element Q3 is greater than or equal to 11 millimeters. The distance between the third switching element Q3 and the second diode D2 in the diode module 513 is the smallest, and this distance d58 is greater than or equal to 10 millimeters. The first diode D1 and the second diode D2 in the diode module 513 are spaced apart from each other along the first direction y, and the distance d52 between them is greater than or equal to 9 millimeters.

[0276] For example, the orthographic projection of the switch module on a plane perpendicular to the first direction overlaps with the orthographic projection of the heat conduction channel on a plane perpendicular to the first direction. For example, referring to Figure 17C , in the first driving structure 501, a partial structure of the switch module 512 is located in the extending direction of the heat conduction channel. In the first driving structure 501, the second switching element Q2 is located between the first switching element Q1 and the third switching element Q3, and the second switching element Q2 is located in the extending direction of the heat conduction channel. In the second driving structure 502, the second switching element Q2' is located between the first switching element Q1' and the third switching element Q3', and the second switching element Q2' is located in the extending direction of the heat conduction channel. In the third driving structure 503, the second switching element Q2'' is located between the first switching element Q1'' and the third switching element Q3'', and a partial structure of the second switching element Q2'' and a partial structure of the first switching element Q1 are located in the extending direction of the heat conduction channel. Considering that the second switching element is located between the first switching element and the third switching element and is subject to heat addition between components, arranging the second switching element in the extending direction of the heat conduction channel is beneficial to the heat dissipation of the second switching element.

[0277] For example, in at least two of the first driving structure, the second driving structure, and the third driving structure, there are non-overlapping portions of the inductance module in the first direction. For example, among the multiple inductance modules in multiple driving structures, at least two inductance modules have non-overlapping portions in the first direction. In this way, by misaligning the inductance modules on the heat dissipation path, the distance between components can be increased, and the blockage of heat can also be reduced, enabling heat to flow faster. For example, referring to Figure 17C , the inductance module 511 of the first driving structure 501, the inductance module 511' of the second driving structure 502, and the inductance module 511'' of the third driving structure 503 are all misaligned. For example, at least two of the first inductance L1 in the inductance module 511, the first inductance L1' in the inductance module 511', and the first inductance L1'' in the inductance module 511'' are misaligned, and at least two of the second inductance L2 in the inductance module 511, the second inductance L2' in the inductance module 511', and the second inductance L2'' in the inductance module 511'' are misaligned.

[0278] For example, in at least two of the first driving structure, the second driving structure, and the third driving structure, the distances between the first inductance and the second inductance in the second direction are the same. For example, among the multiple inductance modules in multiple driving structures, the distances between the first inductance and the second inductance in each inductance module in the second direction are the same. Referring to Figure 17C, in the inductance module 511 of the first driving structure 501, the distance between the first inductor L1 and the second inductor L2 in the second direction x is l1; in the inductance module 511' of the second driving structure 502, the distance between the first inductor L1' and the second inductor L2' in the second direction x is l2; in the inductance module 511" of the third driving structure 503, the distance between the first inductor L1" and the second inductor L2" in the second direction x is l3, and the distances l1, l2, and l3 are all the same.

[0279] For example, the distance between the first inductor of the first driving structure and the first inductor of the second driving structure in the first direction is the same as the distance between the first inductor of the second driving structure and the first inductor of the third driving structure in the first direction. For example, among the multiple inductance modules of multiple driving structures, the distances between the first inductors of every two adjacent driving structures in the first direction are the same. For example, referring to Figure 17C , the distance between the first inductor L1 in the inductance module 511 and the first inductor L1' in the inductance module 511' in the first direction y is l1', and the distance between the first inductor L1' in the inductance module 511' and the first inductor L1" in the inductance module 511" in the first direction y is l2', and the distances l1' and l2' are equal.

[0280] For example, the distance between the second inductor of the first driving structure and the second inductor of the second driving structure in the first direction is the same as the distance between the second inductor of the second driving structure and the second inductor of the third driving structure in the first direction. For example, among the multiple inductance modules of multiple driving structures, the distances between the second inductors of every two adjacent driving structures in the first direction are the same. For example, referring to Figure 17C , the distance between the second inductor L2 in the inductance module 511 and the second inductor L2' in the inductance module 511' in the first direction y is l1", and the distance between the second inductor L2' in the inductance module 511' and the second inductor L2" in the inductance module 511" in the first direction y is l2", and the distances l1" and l2" are equal.

[0281] Such as Figure 17A and Figure 18 As shown, in the voltage conversion unit 5102 of the second driving structure 502 and the voltage conversion unit 5103 of the third driving structure 503, the arrangement of components is basically the same as that of the voltage conversion unit 5101 of the first driving structure 501.

[0282] For example, referring to Figure 17A, the arrangement of the inductance module 511', the switching module 512', and the diode module 513' of the voltage conversion unit 5102 in the second driving structure 502 is the same as that in the first driving structure 501. The output capacitance module 514' and the input capacitance module 515' are located on the side closer to the first edge a1 in the voltage conversion unit 5102, that is, relatively above the inductance module 511'. For example, the arrangement of the components in the voltage conversion unit 5103 of the third driving structure 503 is substantially the same as that of the components in the second driving structure 502.

[0283] Of course, the arrangement of the components in the voltage conversion unit of the second driving structure and the voltage conversion unit of the third driving structure may also be exactly the same as that of the components in the voltage conversion unit of the first driving structure, and can also be adjusted according to actual needs. The present disclosure does not limit this. For example, the arrangement of the components in the light-emitting driving unit in the first driving structure, the second driving structure, and the third driving structure may be exactly the same, or may be slightly different as shown in Figure 17A and can be adjusted according to actual needs. The present disclosure does not limit this.

[0284] According to the embodiment shown in Figures 17A to 18 , after testing the foregoing embodiment for 2 hours in the maximum power state of the components, it is known that in the first driving structure 501, in the switching module 512, the temperature of the second switching element Q2 close to the inductance module 511 is relatively higher, and the temperature is 76.8 °C. Due to the influence of heat rising, in the inductance module 511, the second inductor L2 located higher has a higher temperature, and the temperature is 87.5 °C. In the diode module 513, the temperature of the first diode D1 located higher is higher, and the temperature is 82.5 °C. The temperature of the output capacitance is 69.4 °C. Compared with the embodiment shown in the foregoing Figure 12A , the temperature of the improved switching module 512 drops by 25 °C, the temperature of the inductance module 511 drops by 9 °C, and the temperature of the diode module 513 drops by 10.5 °C. The improvement effect is obvious. Except for the inductance module 511, the temperatures of other components can be controlled within 85 °C. In addition, the inventor also found that the temperature of the output capacitance is relatively high.

[0285] As shown in Figure 15A and Figure 16As shown, for example, the switching module 512 includes at least a first switching element Q1 and a second switching element Q2 connected in parallel. The first switching element Q1 and the second switching element Q2 connected in parallel can not only reduce the conduction loss, but also increase the distance between components, thereby reducing the temperature of the switching module 512 by increasing the distance and combining with reducing the conduction loss. The first switching element Q1 and the second switching element Q2 are arranged at intervals in the second direction x, that is, the first switching element Q1 and the second switching element Q2 are spaced apart from each other, which can reduce the influence of heat generation addition between the two.

[0286] Referring to Figure 15A and 15C , taking the first driving structure 501 as an example, the distance d1 between the first switching element Q1 and the second switching element Q2 in the second direction x is greater than or equal to 8 mm. It can be understood that the distance d1 between the first switching element Q1 and the second switching element Q2 can be but is not limited to 8 mm, 8.1 mm, 8.2 mm, 8.3 mm, 8.4 mm, 8.5 mm, 8.6 mm, 8.7 mm, 8.8 mm, 8.9 mm, 9 mm. Of course, according to the space size of different circuit boards, the distance between the first switching element Q1 and the second switching element Q2 can be even larger, which is not limited here.

[0287] For example, the output capacitor module 514 includes at least a first output capacitor C1 and a second output capacitor C2 connected in parallel. By connecting the first output capacitor C1 and the second output capacitor C2 in parallel, the current on a single component is reduced, thereby reducing the temperature of the first output capacitor C1 and the second output capacitor C2 and increasing the service life of the capacitor module. The first output capacitor C1 and the second output capacitor C2 are arranged at intervals in the first direction y, that is, the first output capacitor C1 and the second output capacitor C2 are arranged in the longitudinal direction of the substrate 600. For example, the distance between the first output capacitor C1 and the second output capacitor C2 in the first direction y is greater than or equal to 2 mm.

[0288] For example, in at least two of the first driving structure, the second driving structure and the third driving structure, the orthographic projection of the output capacitor module on the plane perpendicular to the first direction is at least partially non-overlapping. Referring to Figure 15A and Figure 15D , the output capacitor module 514 in the first driving structure 501 and the output capacitor module 514' in the second driving structure 502 are arranged in a staggered manner in the first direction y. The output capacitor module 514' in the second driving structure 502 and the output capacitor module 514'' in the third driving structure 503 are arranged in a staggered manner in the first direction y.

[0289] For example, in at least two of the first driving structure, the second driving structure, and the third driving structure, the positive projection of the input capacitance module on a plane perpendicular to the first direction is at least partially non-overlapping. Refer to Figure 15A and Figure 15D , the input capacitance module 515 in the first driving structure 501 and the input capacitance module 515' in the second driving structure 502 are misaligned in the first direction y. The input capacitance module 515' in the second driving structure 502 and the input capacitance module 515" in the third driving structure 503 are misaligned in the first direction y.

[0290] For example, the positive projection of the output capacitance module on a plane perpendicular to the second direction at least partially overlaps with the positive projection of the input capacitance module on a plane perpendicular to the second direction. Refer to Figure 15A and Figure 15D , in the first driving structure 501, the output capacitance module 514 and the input capacitance module 515 are spaced apart and relatively arranged in the second direction x. For example, the second output capacitance C2 in the output capacitance module 514 and the input capacitance module 515 are spaced apart and relatively arranged in the second direction x. For example, the second output capacitance C2 at least partially overlaps with the input capacitance module 515 in the second direction x, and the first output capacitance C1 and the input capacitance 515 do not overlap in the second direction x. In the second driving structure 502, the first output capacitance C1' and the input capacitance module 515 partially overlap in the second direction x, and the second output capacitance C2' and the input capacitance module 515 partially overlap in the second direction x. In the third driving structure 503, both the first output capacitance C1" and the second output capacitance C1" also overlap with the input capacitance module 515 in the second direction x.

[0291] For example, refer to Figure 15D , the distance between the switch module 512 of the first driving structure 501 and the switch module 512' of the second driving structure 502 in the first direction y is the same as the distance between the switch module 512' of the second driving structure 502 and the switch module 512" of the third driving structure 503 in the first direction y.

[0292] Combined with some of the foregoing embodiments, only the arrangement in which the first switching element Q1 and the second switching element Q2 are connected in parallel can save the layout space on the surface of the substrate 600. When arranging the first output capacitance C1 and the second output capacitance C2 connected in parallel, more sufficient layout space can be provided for the two, increasing the distance between the output capacitance module 514 and other components.

[0293] Such as Figure 15A and Figure 16As shown, for example, the inductance module 511 includes at least a first inductor L1 and a second inductor L2 connected in parallel. By connecting the first inductor L1 and the second inductor L2 in parallel, the current flowing through the first inductor L1 and the second inductor L2 can be reduced, thereby reducing the temperature of the inductance module 511. The first inductor L1 and the second inductor L2 are spaced apart from each other in the second direction x to reduce the temperature influence between the first inductor L1 and the second inductor L2 and increase the heat dissipation space around the first inductor L1 and the second inductor L2.

[0294] Reference Figure 15A and 15C , for example, the spacing d2 between the first inductor L1 and the second inductor L2 in the second direction x is greater than or equal to 10 millimeters. It can be understood that the spacing d2 between the first inductor L1 and the second inductor L2 in the second direction x includes but is not limited to 10 millimeters, 10.1 millimeters, 10.2 millimeters, 10.3 millimeters, 10.4 millimeters, 10.5 millimeters, 10.5 millimeters, 10.7 millimeters, 10.8 millimeters, 10.9 millimeters, 11 millimeters.

[0295] Reference Figure 15A and 15C , for example, in some usage scenarios of the circuit board, the substrate 600 is arranged at an angle with respect to the ground. Combining with some of the foregoing embodiments, first, the arrangement manner of the components in the voltage conversion unit 510 of the first driving structure 501 is adjusted. For example, Figure 15A the arrangement manner of the components in the second driving structure 502 and the third driving structure 503 shown, can be the same as Figure 17A the arrangement manner of the components shown. For example, in the voltage conversion unit 510 closest to the first edge a1 of the substrate 600, the distance d3 between the inductance module 511 and the outer periphery of the substrate 600 in the first direction y is greater than or equal to 5 millimeters. By adjusting the position of the inductance module 511, a heat dissipation space is reserved between the inductance module 511 and the outer periphery of the substrate 600, facilitating the heat dissipation of the inductance module 511. It can be understood that the distance d3 between any point on the inductance module 511 and any point on the outer periphery of the substrate 600 can be but is not limited to 5 millimeters, 5.1 millimeters, 5.2 millimeters, 5.3 millimeters, 5.4 millimeters, 5.5 millimeters.

[0296] For example, in some usage scenarios of the circuit board, the circuit board housing is provided with a shell to protect the circuit board from dust. By adjusting the position of the inductance module 511 to have a certain distance from the outer periphery of the substrate 600, a larger space can also be reserved between the inductance module 511 and the shell, enabling the inductance module 511 to dissipate heat better.

[0297] Reference Figure 15A and 15C, for example, the spacing d4 between the inductor module 511 and the switch module 512 in the first direction y is greater than or equal to 10 mm. That is to say, the minimum distance between the inductor module 511 and the switch module 512 is greater than or equal to 10 mm. It can be understood that the spacing d4 between any point on the inductor module 511 and any point on the switch module 512 can be, but is not limited to, 10 mm, 10.1 mm, 10.2 mm, 10.3 mm, 10.4 mm, 10.5 mm, 10.6 mm, 10.7 mm, 10.8 mm, 10.9 mm, 11 mm. Of course, the spacing between the inductor module 511 and the switch module 512 can be even larger, which is not limited here. For example, the spacing between the inductor module and the diode module in the second direction is greater than or equal to 12 mm. For example, the spacing between the inductor module and the output capacitor module in the first direction is greater than or equal to 15 mm. For example, the spacing between the inductor module and the input capacitor module in the first direction is greater than or equal to 29 mm.

[0298] Reference Figure 15A and 15C , for example, the spacing d5 between the diode module 513 and the switch module 512 in the first direction y is greater than or equal to 10 mm. That is to say, the minimum distance between the diode module 513 and the switch module 512 is greater than or equal to 10 mm. It can be understood that the spacing d5 between any point on the diode module 513 and any point on the switch module 512 can be, but is not limited to, 10 mm, 10.1 mm, 10.2 mm, 10.3 mm, 10.4 mm, 10.5 mm, 10.6 mm, 10.7 mm, 10.8 mm, 10.9 mm, 11 mm. Of course, the spacing between the diode module 513 and the switch module 512 can be even larger, which is not limited here. For example, the spacing between the diode module and the output capacitor module in the first direction is greater than or equal to 4 mm. For example, the spacing between the switch module and the output capacitor module in the second direction is greater than or equal to 3 mm. For example, the spacing between the switch module and the input capacitor module in the first direction is greater than or equal to 6 mm. For example, the spacing between the switch module and the input capacitor module in the second direction is greater than or equal to 2 mm.

[0299] For example, the diode module 513 includes a first diode D1 and a second diode D2 connected in parallel. The parallel connection of the first diode D1 and the second diode D2 can reduce the temperature of each component, thereby reducing the temperature of the diode module 513. For example, the first diode D1 and the second diode D2 are spaced apart from each other along the first direction y. That is to say, both the first diode D1 and the second diode D2 are arranged on one side of the substrate 600 close to the longitudinal long side. In this way, there can be a relatively large heat dissipation space between the first diode D1 and the second diode D2 and other power components, so that it is easy to dissipate heat from the first diode D1 and the second diode D2.

[0300] Reference Figure 15A and 15C , for example, the distance d6 between the first diode D1 and the second diode D2 in the first direction y is greater than or equal to 9 mm. It can be understood that the distance between the first diode D1 and the second diode D2 in the first direction y can be, but is not limited to, 9 mm, 9.1 mm, 9.2 mm, 9.3 mm, 9.4 mm, 9.5 mm, 9.6 mm, 9.7 mm, 9.8 mm, 9.9 mm, 10 mm. Of course, a larger distance can also be provided between the first diode D1 and the second diode D2, which is not limited here.

[0301] For example, a first conductive layer 610 and a first solder mask layer 620 are provided on one side of the substrate 600 where the light-emitting unit driving circuit 500 is provided. For example, the components in the light-emitting unit driving circuit 500 can be electrically connected to the first conductive layer 610. For example, the material of the first conductive layer 610 includes copper. For example, the first solder mask layer 620 is a green solder mask layer, which functions as insulation and soldering resistance.

[0302] For example, a first opening 621 exposing the first conductive layer 610 is formed in the first solder mask layer 620. The first conductive layer 610 can be exposed through the first opening 621 formed in the first solder mask layer 620, so as to dissipate heat. The first opening 621 surrounds at least one of the inductor module 511, the diode module 513, and the switch module 512, that is, the first opening 621 is formed around at least one of the inductor module 511, the diode module 513, and the switch module 512, thereby improving the heat dissipation efficiency. For example, the first opening 621 can surround all the peripheral regions of at least one of the inductor module 511, the diode module 513, and the switch module 512, or can only surround a part of the peripheral regions of at least one of the inductor module 511, the diode module 513, and the switch module 512. For example, the first opening 621 is a heat dissipation window formed in the first solder mask layer 620.

[0303] For example, the first opening 621 includes a first opening portion 6211, a second opening portion 6212, and a third opening portion 6213. The first opening portion 6211 is located between the inductor module 511, the diode module 513, and the switch module 512, thereby improving the heat generation additive effect among the inductor module 511, the diode module 513, and the switch module 512. For example, the area of the first opening portion 6211 is less than or equal to 800 square millimeters. Compared with the foregoing example, the area of the first opening portion 6211 is reduced by at least 150 square millimeters. For example, the first opening portion 6211 includes a first sub-region, a second sub-region, a third sub-region, and a fourth sub-region. The first sub-region is located between the first inductor L1, the second inductor L2, the first switching element Q1, and the second switching element Q2. The second sub-region is located between the first inductor L1 and the second inductor L2. The third sub-region is located between the first switching element Q1 and the second switching element Q2. The fourth sub-region is located between the second inductor L2 and the first diode D1. For example, the second sub-region, the third sub-region, and the fourth sub-region are all adjacent to the first sub-region. In this way, a more complete first opening portion 6211 can be formed through the adjacency of the four sub-regions, increasing the area of the first opening portion 6211, thereby improving the heat dissipation effect of the first opening portion 6211.

[0304] For example, the second opening portion 6212 surrounds the inductor module 511, and the third opening portion 6213 surrounds the diode module 513. The first opening portion 6211, the second opening portion 6212, and the third opening portion 6213 do not overlap with each other. For example, the second opening portion 6212 surrounds at least a part of the inductor module 511 in the circumferential direction of the inductor module 511, and the third opening portion 6213 surrounds at least a part of the diode module 513 in the circumferential direction of the diode module 513. By arranging the second opening portion 6212 to surround the inductor module 511 and not overlapping with the first opening portion 6211, heat dissipation can be carried out in the circumferential region of the inductor module 511 that is not covered by the first opening portion 6211. By arranging the third opening portion 6213 to surround the diode module 513 and not overlapping with the first opening portion 6211, heat dissipation can be carried out in the circumferential region of the diode module 513 that is not covered by the first opening portion 6211.

[0305] For example, the area of the first opening portion 6211 is larger than the area of the second opening portion 6212, and the area of the first opening portion 6211 is larger than the area of the third opening portion 6213. It can be understood that among the three regions of the first opening 621, the area of the first opening portion 6211 is the largest. The temperatures of the switch module 512 and the inductor module 511 are relatively high, and the larger area of the first opening portion 6211 can dissipate heat more effectively.

[0306] For example, on the side of the substrate 600 away from the first solder mask layer 620, a second conductive layer 630 and a second solder mask layer 640 are further provided. The second conductive layer 630 is located between the second solder mask layer 640 and the first conductive layer 610. For example, the material of the second conductive layer 630 includes copper. For example, the second solder mask layer 640 is a green solder mask layer, which functions as insulation and solder resistance. For example, a second opening 641 exposing the second conductive layer 630 is formed in the second solder mask layer 640, and the orthographic projection of the second opening 641 on a plane parallel to the substrate 600 overlaps with the orthographic projection of the first opening 621 on this plane. The orthographic projections of the first opening 621 and the second opening 641 on a plane parallel to the substrate 600 overlap, that is, the openings on the opposite sides of the substrate 600 correspond to each other. Thus, while the component dissipates heat through the first opening 621, the side where the second opening 641 is located dissipates heat through the second opening 641, improving the heat dissipation efficiency of the circuit board. For example, the second opening 641 is a heat dissipation window formed in the second solder mask layer 640. It can be understood that, Figure 15B only the second opening 641 corresponding to the area where the first driving structure 501 is located is schematically shown. In addition, Figure 15B the shown second opening 641 can be adaptively adjusted in terms of shape, area, and opening position according to actual needs, and the present disclosure does not limit this here.

[0307] For example, the orthographic projection of the first opening 621 on this plane falls within the orthographic projection of the second opening 641 on this plane. On the surface of the substrate 600 where the first opening 621 is located, due to the arrangement of components, the opening of the first opening 621 is more restricted, while the surface where the second opening 641 is located has relatively fewer restrictions. Therefore, a larger heat dissipation opening can be formed for the second opening 641. Moreover, when forming the second opening 641, there is no need to consider the avoidance of components, which also simplifies the manufacturing process during opening and saves costs.

[0308] Such as Figure 15A and Figure 15B shown, in the voltage conversion unit 5102 of the second driving structure 502 and the voltage conversion unit 5103 of the third driving structure 503, the arrangement of components is basically the same as that of the voltage conversion unit 510 of the first driving structure 501. For example, referring to Figure 15A, the arrangement of the inductance module 511', the switch module 512', and the diode module 513' of the voltage conversion unit 5102 in the second driving structure 502 is substantially the same as the arrangement in the first driving structure 501. The output capacitance module 514' and the input capacitance module 551' are located on the side closer to the first edge a1 in the voltage conversion unit 5102, that is, relatively above the inductance module 511'. For example, the diode module 513' is farther from the third edge a3 than the diode module 513. On the one hand, it can avoid the output interface (such as output interfaces CN6 - CN7), and on the other hand, it can also cause the second driving structure 502 to be misaligned with the first driving structure 501 in the second direction x, so that heat can be more easily discharged upward. For example, in the second direction x, the distance between the diode module 513' and the third edge a3 is different from the distance between the diode module 513 and the third edge a3. For example, the first inductor L1' and the second inductor L2' in the inductance module 511' are misaligned in the first direction y, so as to increase the heat dissipation space between the first inductor L1' and the second inductor L2'. For example, the arrangement of the components in the voltage conversion unit 5103 of the third driving structure 503 is substantially the same as the arrangement of the components in the second driving structure 502.

[0309] Of course, the arrangement of the components in the voltage conversion unit of the second driving structure and the voltage conversion unit of the third driving structure can also be exactly the same as the arrangement of the components in the voltage conversion unit of the first driving structure, and can also be adjusted according to actual needs. The present disclosure does not limit this. For example, the arrangement of the components in the light-emitting driving unit in the first driving structure, the second driving structure, and the third driving structure can be the same, or can be slightly different as Figure 15A shown, and can be adjusted according to actual needs. The present disclosure does not limit this.

[0310] For example, it further includes a plurality of vias 601 that at least penetrate the first conductive layer 610 and the second conductive layer 630, and the plurality of vias 601 are arranged in an array. For example, the vias 601 are heat dissipation vias. The vias 601 can conduct the heat of the first conductive layer 610 to the second conductive layer 630, thereby dissipating heat. For example, the vias 601 are electroplated and filled with copper. At least a part of the orthographic projection of the vias 601 on this plane falls within the orthographic projection of the first opening 621 on this plane. It can be understood that the vias 601 are formed at positions where heat dissipation openings are provided around the components. By arranging the vias 601 around the components, the components can be cooled more quickly, realizing the temperature reduction of the components. In addition, the first conductive layer 610 and the second conductive layer 630 can cooperate with the vias 601, and the exposed first conductive layer 610 and the exposed second conductive layer 630 are composed of a whole by the vias 601. While the first conductive layer 610 is dissipating heat, the heat dissipated by the components can be conducted to the other surface more quickly, and further dissipated by means of the second opening 641 exposing the second conductive layer 630, improving the heat dissipation efficiency.

[0311] After testing the foregoing embodiment in the maximum power state of the component for 2 hours, it is known that in the first drive structure 501, in the switching module 512, the second switching element Q2 is greatly affected by the heat addition of other components, and the temperature is relatively higher, and the temperature is 80.3 °C. Compared with Figures 17A to 18 the embodiment shown, the highest temperature of the switching module 512 increases by 3.5 °C. Compared with the embodiment in which the third switching element Q3 is connected in parallel, although the temperature of the second switching element Q2 relatively increases, the change is only about 3 °C, the temperature rise amplitude is small, and the temperature rise effect on other components is also relatively small. In the inductor module 511, the temperature of the first inductor L1 closer to the first switching element Q1 is 84.2 °C, and the temperature of the second inductor L2 closer to the diode module 513 is 86.1 °C. Compared with Figures 17A to 18 the embodiment shown, the highest temperature of the inductor module 511 drops by 1.4 °C. In the diode module 513, the temperature of the relatively upper first diode D1 is higher, and the temperature is 81.2 °C. Compared with Figures 17A to 18 the embodiment shown, the highest temperature of the diode module 513 drops by 1.3 °C. In the output capacitor module 514, the temperature of the relatively upper first output capacitor C1 is higher, and the temperature is 56.2 °C. Compared with Figures 17A to 18 the embodiment shown, the highest temperature of the output capacitor module 514 drops by 13.2 °C. It can be seen from this that except that the temperature of the second inductor L2 is relatively high, exceeding 85 °C by only 1.1 °C, the temperatures of other components can be controlled below 85 °C. At the same time, in the relatively lower second drive structure 502 and third drive structure 503, the temperatures of the components are also below 85 °C.

[0312] Figure 19 Schematic diagram of a housing provided by an example of the present disclosure.

[0313] At least one embodiment of the present disclosure provides a display module, including a backplane, a circuit board as Figure 15A shown, a light-emitting unit, and a housing 900. The circuit board is disposed on the backplane, and the light-emitting unit is disposed on a side of the backplane away from the circuit board and is connected to a driving structure. The light-emitting unit emits light and adjusts its brightness under the driving of the driving structure.

[0314] For example, in some usage scenarios of the circuit board, a housing 900 as Figure 19 shown is further disposed outside the circuit board. On the one hand, the housing 900 can protect the circuit board from external force damage, and on the other hand, it can also prevent dust from entering and causing short circuits or other problems in the circuit board. It can be understood that Figure 19 only the housing 900 is schematically shown, rather than limiting that the shape and structure of the housing disposed outside the circuit board are exactly the same as Figure 19 shown.

[0315] As Figure 19 shown, the housing 900 includes a top wall 910 and a bottom wall 920 that are oppositely disposed in a first direction y. The top wall 910 is provided with a first through hole 911, and the bottom wall 920 is provided with a second through hole 912. Both the first through hole 911 and the second through hole 912 communicate the internal space and the external space of the housing 900. The first through hole 911 and the second through hole 912 can dissipate heat from both sides of the circuit board in the first direction y, accelerating the heat exchange between the internal and external spaces of the housing 900 and improving the heat dissipation efficiency.

[0316] Combined with Figure 19 and Figure 15A shown, in some usage scenarios of the display module, the housing 900, the circuit board inside the housing 900, and the ground are disposed at an angle. For example, the first direction y is the longitudinal direction of the substrate 600 in the circuit board, and the first direction y is disposed at an angle with the ground. Since heat propagates upward away from the ground, the first through hole 911 and the second through hole 912 that communicate the internal and external spaces of the housing 900 can form a convection cycle, thereby dissipating heat.

[0317] For example, a plurality of first through-holes 911 are provided, and the plurality of first through-holes 911 are arranged at intervals in a second direction x, and the second direction x is parallel to the substrate 600 and intersects with a first direction y. For example, the second direction x is perpendicular to the first direction y. A plurality of second through-holes 912 are provided, and the plurality of second through-holes 912 are arranged at intervals in the second direction x. For example, the second direction x is the width direction of the substrate 600 in the circuit board. By providing a plurality of first through-holes 911 and a plurality of second through-holes 912, the opening area of the top wall 910 and the bottom wall 920 can be increased, thereby increasing the heat dissipation area. Moreover, the plurality of first through-holes 911 and the plurality of second through-holes 912 can also more easily form a convection cycle to accelerate heat dissipation.

[0318] As Figure 19 shown, taking the dimension of the housing 900 in the first direction y as 115 mm and the dimension in the second direction x as 15 mm as an example, the number of the first through-holes 911 is set to be not less than 9, and the number of the second through-holes 912 is set to be not less than 9. For example, the diameters of the first through-holes 911 and the second through-holes 912 are not less than 6 mm. For example, the plurality of first through-holes 911 and the plurality of second through-holes 912 are both evenly arranged in the second direction x. Of course, the present disclosure does not limit this here, and the number and size of the first through-holes 911 and the second through-holes 912 can also be set according to actual needs.

[0319] For example, the housing 900 further includes a side wall 930 connecting the top wall 910 and the bottom wall 920, and the side wall 930 is provided with a third through-hole 931. Combining Figure 19 and Figure 15A shown, for example, a plurality of third through-holes 931 are provided in two side walls 930 of the housing 900 parallel to the surface of the substrate 600 of the circuit board, and the plurality of third through-holes 931 are arranged in an array. In this way, the housing 900 can also achieve heat exchange between the internal and external spaces of the housing 900 by means of the plurality of third through-holes 931, further improving the heat dissipation efficiency of the components on the circuit board. For example, the orthographic projection of the third through-hole 931 on a third reference plane overlaps with the orthographic projection of the driving structure on the third reference plane, and the third reference plane is parallel to the substrate. For example, the third through-hole 931 corresponds to the position where the components in the driving structure are located for easy heat dissipation. For example, the third through-hole 931 basically corresponds to the positions where the voltage conversion unit 510 and the light-emitting driving unit 520 are located. For example, referring to Figure 19 , the third through-hole 9311 near the first through-hole 911 can correspond to Figure 15A the voltage conversion unit 5101 in Figure 15A , the third through-hole 9313 near the second through-hole 912 can correspond to Figure 15A the light-emitting driving unit 5203 in

[0320] After testing the foregoing embodiments in the maximum power state of the components for 2 hours, it is known that the light-emitting units in the display module generate heat, causing the temperature of the backplane to rise to 52 °C. However, the temperatures of all components in the circuit board are reduced to below 85 °C, and the highest temperature is only 83.4 °C. All components meet the temperature rise requirements.

[0321] At least one embodiment of the present disclosure provides a display device including the above-mentioned display module.

[0322] For example, the display device provided by the embodiments of the present disclosure may be: a liquid crystal display, a television, an electronic paper display device, a mobile phone, a tablet computer, a notebook computer, a digital photo frame, a navigator, a virtual reality device, or any product or component with a display function. It should be noted that the display device may further include other conventional components or structures. For example, to implement the necessary functions of the display device, those skilled in the art may set other conventional components or structures according to specific application scenarios, and the embodiments of the present disclosure do not limit this.

[0323] Since the display device according to the embodiments of the present disclosure includes the above-mentioned display module, it also has corresponding beneficial technical effects, which will not be elaborated here.

[0324] The following points need to be explained:

[0325] (1) In the accompanying drawings of the embodiments of the present disclosure, only the structures related to the embodiments of the present disclosure are involved, and other structures may refer to the general design.

[0326] (2) Without conflict, the features in the same embodiment and different embodiments of the present disclosure may be combined with each other.

[0327] The above is only an exemplary embodiment of the present disclosure and is not used to limit the protection scope of the present disclosure. The protection scope of the present disclosure is determined by the appended claims.

Claims

1. A circuit board, comprising: A substrate; A plurality of voltage conversion units and a plurality of light-emitting driving units disposed on the substrate, the voltage conversion unit including an input end and an output end and being configured to output a preset voltage; The light-emitting driving unit is connected to the output end of the voltage conversion unit and is configured to drive a light-emitting unit; Wherein, the plurality of voltage conversion units and the plurality of light-emitting driving units are arranged in one-to-one correspondence, and a voltage conversion unit is arranged between adjacent light-emitting driving units; The voltage conversion unit includes a first inductor and a second inductor connected in parallel, and the first inductor and the second inductor are arranged in a staggered manner.

2. The circuit board according to claim 1, wherein The circuit board includes a first edge close to the voltage conversion unit in a first direction, and the first direction is a direction from the voltage conversion unit to the light-emitting driving unit; The distance between the first inductor and the first edge in the first direction is a first distance, the distance between the second inductor and the first edge in the first direction is a second distance, and the first distance is different from the second distance.

3. The circuit board according to claim 2, wherein, The difference between the first distance and the second distance is less than or equal to 1 / 2 of the width dimension of the first inductor in the first direction.

4. The circuit board according to claim 1, wherein, The plurality of voltage conversion units include a first voltage conversion unit and a second voltage conversion unit located on both sides of a first light-emitting driving unit in a first direction, and the first direction is a direction from the voltage conversion unit to the light-emitting driving unit; The first voltage conversion unit includes a first inductor module, and the second voltage conversion unit includes a second inductor module; the interval between the first inductor module and the second inductor module in the first direction is y, the positive projection of the first inductor on a first reference plane and the positive projection of the second inductor on the first reference plane have non-overlapping parts, the dimension of the non-overlapping part in the first direction is h, and the dimension of the light-emitting driving unit in the first direction is x, then: y = a×x + b×h, 2 < a < 4, 1 < b < 3; Wherein, the second direction intersects with the first direction, and the first reference plane is a plane perpendicular to the second direction.

5. The circuit board according to claim 1, wherein, The plurality of voltage conversion units include a first voltage conversion unit and a second voltage conversion unit located on both sides of a first light-emitting driving unit, the first voltage conversion unit includes a first inductor module, a first capacitor module and a first switch module, and the second voltage conversion unit includes a second inductor module; The interval between the first inductor module and the second inductor module in the first direction is y, the dimension of the first inductor module in the first direction is y1, the dimension of the first capacitor module in the first direction is y2, and the dimension of the first switch module in the first direction is y3, then: y = k×y1 + y3 + 2×y2, 1 < k < 3; Wherein, the first direction is a direction from the voltage conversion unit to the light-emitting driving unit.

6. The circuit board according to claim 1, wherein, The multiple voltage conversion units include a first voltage conversion unit and a second voltage conversion unit located on both sides of the first light-emitting driving unit. The first voltage conversion unit includes a first inductor module, a first capacitor module, and a first switch module; The first inductor module includes the first inductor and the second inductor connected in parallel with each other. The first inductor and the second inductor have a first interval in the second direction. The first capacitor module includes a first output capacitor module and a first input capacitor module connected in parallel with each other. The first output capacitor module and the first input capacitor module have a second interval in the second direction. The first switch module includes a first switch and a second switch connected in parallel with each other. The first switch and the second switch have a third interval in the second direction. The second voltage conversion unit includes a second capacitor module. The second capacitor module includes a second output capacitor module and a second input capacitor module connected in parallel with each other. The second output capacitor module and the second input capacitor module have a fourth interval in the second direction. The fourth interval and at least one of the first interval, the second interval, and the third interval have an overlapping part on a second reference plane. The second reference plane is a plane perpendicular to the first direction. The first direction is the direction from the voltage conversion unit to the light-emitting driving unit. The second direction is parallel to the substrate and intersects the first direction.

7. The circuit board according to claim 6, wherein, The first interval, the second interval, the third interval, and the fourth interval have a common overlapping part on the second reference plane.

8. The circuit board according to claim 7, wherein, The size of the common overlapping part in the second direction is less than or equal to the size of the first interval in the second direction.

9. The circuit board according to claim 7, wherein, The ratio of the size of the common overlapping part in the second direction to the size of the first interval in the second direction is 0.3 to 0.

7.

10. The circuit board according to claim 6, wherein, The first interval, the second interval, the third interval, and the fourth interval are configured to satisfy at least one of the following conditions: The first interval is greater than or equal to 10 millimeters; The second interval is greater than or equal to 28 millimeters; The third interval is greater than or equal to 8 millimeters; The fourth interval is greater than or equal to 4 millimeters.

11. The circuit board according to claim 6, wherein, The second voltage conversion unit includes a second inductor module. The second inductor module includes a third inductor and a fourth inductor oppositely arranged in the second direction; The first interval is configured to satisfy at least one of the following conditions: The positive projection of the first interval on the second reference plane and the positive projection of the third inductor or the fourth inductor on the second reference plane have a first overlapping part. The size of the first overlapping part in the second direction is greater than 1 / 3 of the size of the third inductor or the fourth inductor in the second direction; The positive projection of the first interval on the second reference plane and the positive projection of the second input capacitor module on the second reference plane have a third overlapping part. The size of the third overlapping part in the second direction is greater than 1 / 3 of the size of the second input capacitor module in the second direction.

12. The circuit board according to claim 11, wherein, The dimension of the first interval in the second direction is the same as the spacing between the third inductor and the fourth inductor in the second direction.

13. The circuit board according to claim 6, wherein, The second interval is configured to satisfy at least one of the following conditions: The second voltage conversion unit includes a second inductor module, and the orthographic projection of the second interval on the second reference plane at least partially overlaps with the orthographic projection of the second inductor module on the second reference plane; There is an eighth overlapping portion between the orthographic projection of the second interval on the second reference plane and the orthographic projection of the second output capacitor module or the second input capacitor module on the second reference plane, and the dimension of the eighth overlapping portion in the second direction is greater than 2 / 3 of the dimension of the second output capacitor module or the second input capacitor module in the second direction.

14. The circuit board according to claim 6, wherein, The second voltage conversion unit includes a second inductor module, and the second inductor module includes a third inductor and a fourth inductor that are oppositely arranged in the second direction; The second interval is configured to satisfy at least one of the following conditions: The dimension of the second interval in the second direction is greater than the dimension of the first inductor or the second inductor in the second direction; There is a sixth overlapping portion between the orthographic projection of the second interval on the second reference plane and the orthographic projection of the first inductor or the second inductor on the second reference plane, and the dimension of the sixth overlapping portion in the second direction is greater than 1 / 3 of the dimension of the first inductor in the second direction; The orthographic projection of the second interval on the second reference plane at least partially overlaps with the orthographic projection of the third inductor on the second reference plane; The orthographic projection of the second interval on the second reference plane completely overlaps with the orthographic projection of the fourth inductor on the second reference plane.

15. The circuit board according to claim 6, wherein, The second voltage conversion unit includes a second inductor module, and the second inductor module includes a third inductor and a fourth inductor that are oppositely arranged in the second direction; The third interval is configured to satisfy at least one of the following conditions: There is a fourteenth overlapping portion between the orthographic projection of the third interval on the second reference plane and the orthographic projection of the third inductor or the fourth inductor on the second reference plane; There is a sixteenth overlapping portion between the orthographic projection of the third interval on the second reference plane and the orthographic projection of the second output capacitor module or the second input capacitor module on the second reference plane.

16. The circuit board according to claim 15, wherein, The dimension of the fourteenth overlapping portion in the second direction is greater than 1 / 2 of the dimension of the third inductor or in the second direction; and / or, The dimension of the sixteenth overlapping portion in the second direction is greater than 1 / 3 of the dimension of the second output capacitor module or the second input capacitor module in the second direction.

17. The circuit board according to claim 6, wherein, The second voltage conversion unit includes a second inductor module; There is a non-overlapping portion between the orthographic projection of the first inductor module on the second reference plane and the orthographic projection of the second inductor module on the second reference plane.

18. The circuit board according to claim 1, wherein, The voltage conversion unit includes an inductor module, a diode module, a switch module, an output capacitor module, and an input capacitor module; The inductance module is connected between the input end of the voltage conversion unit and the positive electrode of the diode module; The negative electrode of the diode module is connected to the output end of the voltage conversion unit; The switch module includes a control end, an input end, and an output end. The control end of the switch module is configured to receive a control signal, and the control signal is used to control the conduction or cutoff between the input end and the output end of the switch module. One of the input end and the output end of the switch module is connected between the inductance module and the diode module, and the other of the input end and the output end of the switch module is connected to the ground end; The first pole of the output capacitance module is connected to the negative electrode of the diode module, and the second pole of the output capacitance module is connected to the ground end; The input capacitance module is connected between the input end and the ground end.

19. The circuit board according to claim 18, wherein, The substrate includes a first edge and a second edge disposed opposite to each other in a first direction. In each of the driving structures, the first direction is the direction from the voltage conversion unit to the light-emitting driving unit; At least in the voltage conversion unit closest to the first edge of the substrate, The inductance module is disposed on a side of the voltage conversion unit away from the light-emitting driving unit in the first direction; The output capacitance module is disposed on a side of the voltage conversion unit close to the light-emitting driving unit in the first direction; The input capacitance module and the output capacitance module are disposed opposite to each other in a second direction, and the second direction is parallel to the substrate and intersects with the first direction; The diode module is closer to the third edge of the substrate than the inductance module and the output capacitance module, and the third edge connects the first edge and the second edge; The switch module is disposed between the inductance module and the output capacitance module.

20. The circuit board according to claim 18 or 19, wherein, The circuit board is configured to satisfy at least one of the following conditions: The switch module includes at least a first switch element and a second switch element connected in parallel; the distance between the first switch element and the second switch element in the second direction is greater than or equal to 8 millimeters; The output capacitance module includes at least a first output capacitance module and a second output capacitance module connected in parallel; The distance between the first output capacitance module and the second output capacitance module in the first direction is greater than or equal to 2 millimeters; In the voltage conversion unit closest to the first edge of the substrate, the distance between the inductance module and the outer periphery of the substrate in the first direction is greater than or equal to 5 millimeters; The diode module includes a first diode and a second diode connected in parallel, and the distance between the first diode and the second diode in the first direction is greater than or equal to 9 millimeters; Wherein, the first direction is the direction from the voltage conversion unit to the light-emitting driving unit, and the second direction is parallel to the substrate and intersects with the first direction.

21. The circuit board according to claim 18 or 19, wherein, The voltage conversion unit is configured to satisfy at least one of the following conditions: The distance between the inductance module and the switch module in the first direction is greater than or equal to 10 millimeters; The distance between the inductor module and the diode module in the second direction is greater than or equal to 12 millimeters; The distance between the inductor module and the output capacitor module in the first direction is greater than or equal to 15 millimeters; The distance between the inductor module and the input capacitor module in the first direction is greater than or equal to 29 millimeters; The distance between the diode module and the switch module in the second direction is greater than or equal to 10 millimeters; The distance between the diode module and the output capacitor module in the first direction is greater than or equal to 4 millimeters; The distance between the switch module and the output capacitor module in the second direction is greater than or equal to 3 millimeters; The distance between the switch module and the input capacitor module in the first direction is greater than or equal to 6 millimeters; The distance between the switch module and the input capacitor module in the second direction is greater than or equal to 2 millimeters.

22. The circuit board according to claim 18 or 19, wherein, The diode module includes a Schottky diode; and / or The switch module includes a transistor.

23. The circuit board according to claim 1, wherein, The voltage conversion units are provided in multiple numbers, and the light-emitting driving units are provided in multiple numbers; the multiple voltage conversion units and the multiple light-emitting driving units are arranged in one-to-one correspondence, and the corresponding voltage conversion unit and the light-emitting driving unit are connected to form multiple driving structures; The multiple driving structures are arranged in sequence along the first direction, and the multiple light-emitting driving units and the multiple voltage conversion units are alternately arranged along the first direction; The multiple driving structures include a first driving structure and a second driving structure, the first driving structure includes a first voltage conversion unit and a first light-emitting driving unit, and the second driving structure includes a second voltage conversion unit and a second light-emitting driving unit; The first driving structure and the second driving structure are configured to satisfy at least one of the following conditions: There is a non-overlapping part between the orthographic projection of the first voltage conversion unit on the second reference plane and the orthographic projection of the second voltage conversion unit on a plane perpendicular to the first direction; The second reference plane is a plane perpendicular to the first direction; There is a non-overlapping part between the orthographic projection of the first light-emitting driving unit on the second reference plane and the orthographic projection of the second light-emitting driving unit on the second reference plane; There is a non-overlapping part between the orthographic projection of the first voltage conversion unit on the second reference plane and the orthographic projection of the first light-emitting driving unit on the second reference plane; There is a non-overlapping part between the orthographic projection of the first voltage conversion unit on the second reference plane and the orthographic projection of the second light-emitting driving unit on the second reference plane; There is a non-overlapping part between the orthographic projection of the second voltage conversion unit on the second reference plane and the orthographic projection of the second light-emitting driving unit on the second reference plane; There is a non-overlapping part between the orthographic projection of the second voltage conversion unit on the second reference plane and the orthographic projection of the first light-emitting driving unit on the second reference plane.

24. The circuit board according to claim 23, wherein, The first voltage conversion unit includes a first diode module and a first input capacitor module, and the first light-emitting driving unit includes a first switching tube module and a first driving module; the second voltage conversion unit includes a second output capacitor module and a second inductor module, and the second light-emitting driving unit includes a second switching tube module and a second driving module; The first driving structure and the second driving structure are configured to satisfy at least one of the following conditions: A first non-overlapping portion exists between the orthographic projection of the first diode module on the second reference plane and the orthographic projection of the second output capacitor module on the second reference plane; A second non-overlapping portion exists between the orthographic projection of the first input capacitor module on the second reference plane and the orthographic projection of the second inductor module on the second reference plane; A third non-overlapping portion exists between the orthographic projection of the first switching tube module on the second reference plane and the orthographic projection of the second switching tube module on the second reference plane; A fourth non-overlapping portion exists between the orthographic projection of the first driving module on the second reference plane and the orthographic projection of the second driving module on the second reference plane; A fifth non-overlapping portion exists between the orthographic projection of the first diode module on the second reference plane and the orthographic projection of the first switching tube module on the second reference plane; A sixth non-overlapping portion exists between the orthographic projection of the first input capacitor module on the second reference plane and the orthographic projection of the first driving module on the second reference plane; A seventh non-overlapping portion exists between the orthographic projection of the first diode module on the second reference plane and the orthographic projection of the second switching tube module on the second reference plane; An eighth non-overlapping portion exists between the orthographic projection of the first input capacitor module on the second reference plane and the orthographic projection of the second driving module on the second reference plane; A ninth non-overlapping portion exists between the orthographic projection of the first switching tube module on the second reference plane and the orthographic projection of the second output capacitor module on the second reference plane; A tenth non-overlapping portion exists between the orthographic projection of the first driving module on the second reference plane and the orthographic projection of the second inductor module on the second reference plane; An eleventh non-overlapping portion exists between the orthographic projection of the second output capacitor module on the second reference plane and the orthographic projection of the second switching tube module on the second reference plane; A twelfth non-overlapping portion exists between the orthographic projection of the second inductor module on the second reference plane and the orthographic projection of the second driving module on the second reference plane.

25. The circuit board according to claim 1, wherein, The substrate includes a first conductive layer and a first solder mask layer. The first conductive layer and the first solder mask layer are located on the side of the substrate where the light-emitting driving unit is provided, and the first conductive layer is located on the side of the first solder mask layer away from the light-emitting driving unit; The voltage conversion unit includes an inductor module, a diode module, and a switching module. The inductor module includes the first inductor and the second inductor; A first opening exposing the first conductive layer is formed in the first solder mask layer; the first opening surrounds at least one of the inductor module, the diode module, and the switching module.

26. The circuit board according to claim 25, wherein, The first opening includes a first opening portion, a second opening portion, and a third opening portion that do not overlap each other; The first opening portion is located between the inductor module, the diode module, and the switch module, the second opening portion surrounds the inductor module, and the third opening portion surrounds the diode module; wherein, the area of the first opening portion is larger than the area of the second opening portion, and the area of the first opening portion is larger than the area of the third opening portion.

27. The circuit board according to claim 26, wherein, The area of the first opening portion is less than or equal to 800 square millimeters; The area of the second opening portion is greater than or equal to 320 square millimeters; The area of the third opening portion is greater than or equal to 90 square millimeters.

28. The circuit board according to claim 25, wherein, The substrate includes a second conductive layer and a second solder mask layer on a side of the first conductive layer away from the first solder mask layer, and the second conductive layer is located between the second solder mask layer and the first conductive layer; A second opening exposing the second conductive layer is formed in the second solder mask layer; a positive projection of the second opening on a third reference plane overlaps a positive projection of the first opening on the third reference plane; The third reference plane is parallel to the substrate.

29. The circuit board according to claim 28, further comprising: A plurality of vias penetrating at least the first conductive layer and the second conductive layer, and the plurality of vias are arranged in an array; A positive projection of the first opening on the third reference plane covers at least a part of a positive projection of the plurality of vias on the third reference plane.

30. The circuit board according to any one of claims 1-29, further comprising a shielding component; The shielding component is disposed at least on opposite sides of the light emitting driving unit in a first direction, and the first direction is a direction from the voltage conversion unit to the light emitting driving unit.

31. A display module, comprising: A backplane; The circuit board according to any one of claims 1-30, disposed on the backplane; A light emitting unit, disposed on a side of the backplane away from the circuit board and connected to the driving structure; And A housing covering the outside of the circuit board; Wherein, the housing includes a top wall and a bottom wall oppositely disposed in a first direction; the first direction is a direction from the voltage conversion unit to the light emitting driving unit; the housing is configured to satisfy at least one of the following conditions: The top wall is provided with a first through hole, and the first through hole communicates the internal space and the external space of the housing; The bottom wall is provided with a second through hole, and the second through hole communicates the internal space and the external space of the housing.

32. The display module according to claim 31, wherein, The housing further includes a side wall connecting the top wall and the bottom wall, and the side wall is provided with a third through hole; A positive projection of the third through hole on a third reference plane overlaps a positive projection of the driving structure on the third reference plane; the third reference plane is parallel to the substrate.

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