Circuit board, backlight structure, and display panel

Abstract

A circuit board, a backlight structure, and a display panel. The circuit board comprises at least one driving assembly. The driving assembly comprises at least one pad group (10) and at least one signal transmission line (40), wherein the pad group (10) comprises a first sub-pad group (101), and the first sub-pad group (101) comprises a first pad (11) and a second pad (12) independent of each other; the pad group (10) is used for connecting to a corresponding light-emitting element (20), the first pad (11) is used for connecting to a first electrode of the light-emitting element (20), and the second pad (12) is used for connecting to a second electrode of the light-emitting element (20); the signal transmission line (40) is connected to both a corresponding signal input end and the first pad (11) in the corresponding first sub-pad group (101); and the resistance of the signal transmission line (40) satisfies that the potential difference between the first pad (11) and the second pad (12) is less than a target threshold value.

Description

Circuit board, backlight structure and display panel

[0001] Cross-reference of related applications

[0002] This application claims priority to Chinese Patent Application No. 202410684123.5, filed in China on May 29, 2024, the entire contents of which are incorporated herein by reference. Technical Field

[0003] This disclosure relates to the field of display technology, and more particularly to a circuit board, a backlight structure, and a display panel. Background Technology

[0004] With the continuous development of display technology, the application fields of display products are becoming increasingly wide, and the types of display products are also increasing. Currently, Mini-LED (sub-millimeter light-emitting diode) is developing rapidly. It is considered a transitional product to Micro-LED (micro light-emitting diode). Due to the immaturity of Micro-LED technology and the great difficulty of mass transfer technology, Mini-LED has received extensive research. Furthermore, because Mini-LED has advantages such as better display effect, thinner and lighter design, higher contrast ratio, and longer lifespan, people are constantly optimizing its design, trying to design even better products.

[0005] However, when Mini-LEDs are applied to actual display products, bubbling defects can easily occur on the pads when Mini-LEDs are soldered onto the pads, which in turn affects the yield of the display products. Summary of the Invention

[0006] The purpose of this disclosure is to provide a circuit board, a backlight structure, and a display panel.

[0007] To achieve the above objectives, this disclosure provides the following technical solution:

[0008] A first aspect of this disclosure provides a circuit board including at least one set of driving components; the driving components include:

[0009] At least one set of pads, the pads group including a first sub-pad group, the first sub-pad group including a first pad and a second pad that are independent of each other; the pads group is used to connect corresponding light-emitting elements, the first pad is used to connect the first electrode of the light-emitting element, and the second pad is used to connect the second electrode of the light-emitting element.

[0010] At least one signal transmission line is provided, which is connected to a corresponding signal input terminal and a first pad in the corresponding first sub-pad group; the resistance of the signal transmission line satisfies that the potential difference between the first pad and the second pad is less than a target threshold.

[0011] Optionally, the driving component includes:

[0012] At least two sets of pads;

[0013] At least two signal transmission lines, each signal transmission line including a connected bus and a branch line, wherein the at least two signal transmission lines multiplex the same bus, the bus is connected to the signal input terminal, and the branch line is connected to the first pad in the corresponding pad group;

[0014] The resistance of the branch line satisfies the condition that the potential difference between the first pad and the second pad in its corresponding pad group is less than the target threshold.

[0015] Optionally, in the same group of drive components, at least some of the branches of the first pads connected to the first pads in the first sub-pad group have equal resistance.

[0016] Optionally, in the same group of drive components, at least a portion of the first sub-pad groups include branches with the same thickness for the first pad connections, and at least a portion of the first sub-pad groups include branches with the same line length to line width ratio for the first pad connections.

[0017] Optionally, the branch line includes at least two line segments connected in sequence, with adjacent line segments extending in different directions. The starting line segment of the at least two line segments is connected to the corresponding bus, and the ending line segment of the at least two line segments is connected to the first pad in the corresponding first sub-pad group. The resistance of the branch line is the sum of the resistances of all the line segments it includes.

[0018] Optionally, the at least two line segments are arranged in the same layer and with the same material; or, of the at least two line segments, a portion of the line segments are arranged in different layers from another portion of the line segments.

[0019] Optionally, in the same group of driving components, the at least two groups of pads are arranged sequentially along a first direction; the circuit board includes multiple groups of the driving components, which are arranged along a second direction, the second direction intersecting the first direction;

[0020] The circuit board further includes a power supply circuit located on one side of the plurality of drive components along the first direction, and the power supply circuit includes a plurality of signal input terminals.

[0021] Optionally, in at least one of the starting drive component, the ending drive component, and the intermediate drive component included in the plurality of drive components, the line length of the branch coupled to each of the first sub-pad groups along the first direction increases sequentially, and the line width of the branch coupled to each of the first sub-pad groups along the first direction increases sequentially.

[0022] Optionally, in at least one of the starting drive component, the ending drive component, and the intermediate drive component included in the plurality of drive components, the line length of the branch coupled to each of the first sub-pad groups along the first direction increases proportionally, and the line width of the branch coupled to each of the first sub-pad groups along the first direction increases proportionally.

[0023] Optionally, the plurality of drive components further includes a plurality of transition drive components, a portion of which is located between the starting drive component and the intermediate drive component, and another portion of which is located between the intermediate drive component and the ending drive component.

[0024] In the transition drive assembly, at least two adjacent first sub-pad groups include signal transmission lines connected to the first pads that multiplex at least a portion of the same branch line.

[0025] Optionally, in the intermediate drive component and the multiple sets of transition drive components, in at least two partially adjacent sets of drive components, the signal transmission lines of each set of drive components share the same bus.

[0026] Optionally, the pad group further includes at least one second sub-pad group, the second sub-pad group including mutually independent third and fourth pads; the second sub-pad group is used to connect the corresponding light-emitting element, the third pad is used to connect the first electrode of the light-emitting element, and the fourth pad is used to connect the second electrode of the light-emitting element;

[0027] In the case where the pad group includes a second sub-pad group, the second pad is connected to the third pad in the second sub-pad group;

[0028] When the pad group includes at least two second sub-pad groups, the second pad is connected to the third pad in the first second sub-pad group, the at least two second sub-pad groups are connected in series, and in the two connected second sub-pad groups, the fourth pad of one second pad group is connected to the third pad of the other second pad group.

[0029] Optionally, the pad group includes three second sub-pad groups; the fourth pad in the first second sub-pad group is connected to the third pad in the second second sub-pad group, and the fourth pad in the second second sub-pad group is connected to the third pad in the third second sub-pad group.

[0030] Based on the above-described circuit board technical solution, a second aspect of this disclosure provides a backlight structure, including the circuit board described above; the backlight structure further includes a light-emitting element, wherein a first electrode of the light-emitting element is connected to a first pad in a corresponding pad group on the circuit board, and a second electrode of the light-emitting element is connected to a second pad in the corresponding pad group.

[0031] Based on the above-described circuit board technical solution, a second aspect of this disclosure provides a display panel including the circuit board described above; the display panel further includes a light-emitting element, a first electrode of the light-emitting element being connected to a first pad in a corresponding pad group in the circuit board, and a second electrode of the light-emitting element being connected to a second pad in the corresponding pad group. Attached Figure Description

[0032] The accompanying drawings, which are included to provide a further understanding of this disclosure and form part of this disclosure, illustrate exemplary embodiments of the present disclosure and are used to explain the disclosure, but do not constitute an undue limitation of the disclosure. In the drawings:

[0033] Figure 1 is a schematic diagram of bubbling on the first pad provided in an embodiment of this disclosure;

[0034] Figure 2 is a first layout schematic diagram of the start-up drive component provided in an embodiment of this disclosure;

[0035] Figure 3 is a schematic diagram of the layout of a portion of the circuit board provided in an embodiment of this disclosure;

[0036] Figure 4 is a schematic diagram of the signal transmission line layout in Figure 3;

[0037] Figure 5 is a schematic diagram of the layout of the pad group in Figure 3;

[0038] Figure 6 is a schematic diagram of the second layout of the start-up drive component provided in an embodiment of this disclosure;

[0039] Figure 7 is a schematic diagram of the layout of the transition drive component provided in an embodiment of this disclosure;

[0040] Figure 8 is a schematic diagram of the layout of the intermediate driving component provided in an embodiment of this disclosure;

[0041] Figure 9 is a schematic diagram of the signal transmission line layout in Figure 8;

[0042] Figure 10 is a schematic diagram of the layout of the pad group in Figure 8. Detailed Implementation

[0043] To further illustrate the circuit board, backlight structure, and display panel provided in the embodiments of this disclosure, a detailed description is provided below with reference to the accompanying drawings.

[0044] As shown in Figure 1, in Mini-LED products, when mounting Mini-LEDs onto pads on a printed circuit board (PCB) using surface mount technology (SMT), a reflow soldering process is required to heat the solder paste on the PCB pads, thereby fixing the Mini-LED components onto the pads. However, after the reflow process, bubbling defects (30) were found on the pads during Automatic Optical Inspection (AOI).

[0045] Research revealed that the blistering pads were concentrated on the pads connected to the P-electrode of the Mini-LED, and the P-electrode of these pads is always connected to a relatively wide signal transmission line. Focused ion beam (FIB) and energy-dispersive X-ray spectroscopy (EDX) analyses showed that the blistering initiation point was located at the corner of the P-electrode, and irregular abnormal substances, composed of Sn (tin), were found in the Cu layer of the pads.

[0046] The blistering pads are concentrated on the pads connected to the P-electrode of Mini-LEDs. This is because, during the ENIG process, a significant potential difference exists between the P and N electrodes. This results in different states at the interface between the Cu and Ni (nickel) layers after gold plating. Specifically, the reaction voids at the P-electrode interface are more severe than those at the N-electrode. As a result, after the SMT reflow process, Sn paste flows along the gold plating interface on the side of the pad into the Cu surface, reacting with the Cu until the Cu layer breaks down. The Sn paste then flows along the Cu underlayer towards the outside of the pad, causing what appears as blister-like marks around the P-electrode pads during AOI inspection. These marks are actually traces of Sn paste flowing through the Cu underlayer. It's important to note that ENIG (Electroless Nickel / Immersion Gold) is a common surface treatment technology for printed circuit boards, encompassing electroless nickel / immersion gold processes. This treatment forms a two-layer protective coating: a nickel underlayer and a gold top layer.

[0047] Based on this, the following design scheme is proposed to reduce the potential difference between the PN electrodes, in order to solve the problem that bubbling defects easily occur on the pads when Mini-LEDs are soldered onto the pads, which in turn affects the yield of display products.

[0048] Please refer to Figures 1 to 5. This disclosure provides a circuit board including at least one set of driving components; the driving components include:

[0049] At least one set of pad groups 10, the pad group 10 including a first sub-pad group 101, the first sub-pad group 101 including a first pad 11 and a second pad 12 that are independent of each other; the pad group 10 is used to connect the corresponding light-emitting element 20, the first pad 11 is used to connect the first electrode of the light-emitting element 20, and the second pad 12 is used to connect the second electrode of the light-emitting element 20.

[0050] At least one signal transmission line 40 is provided, which is connected to the corresponding signal input terminal (located in the bonding area 50) and the first pad 11 in the corresponding first sub-pad group 101 respectively; the resistance of the signal transmission line 40 satisfies that the potential difference between the first pad 11 and the second pad 12 is less than the target threshold.

[0051] For example, the circuit board includes a printed circuit board, but is not limited to this.

[0052] For example, the driving component includes one or more pad groups 10, the pad group 10 including a first sub-pad group 101, the first sub-pad group 101 including a first pad 11 and a second pad 12 disposed opposite to each other, the first pad 11 and the second pad 12 being spaced apart and having a gap area between them.

[0053] For example, the pad group 10 is used to connect a corresponding light-emitting element 20, which includes, but is not limited to, a Mini-LED. Specific connection methods include soldering with solder paste, but are not limited to this. The first pad 11 is used to solder the first electrode of the light-emitting element 20, and the second pad 12 is used to solder the second electrode of the light-emitting element 20.

[0054] For example, the driving component includes at least one signal transmission line 40, which corresponds one-to-one with the at least one set of pad groups 10, but is not limited thereto. The signal transmission line 40 is connected to the corresponding signal input terminal and the first pad 11 in the corresponding pad group 10, respectively. It is worth noting that each signal transmission line 40 may be selectively connected to the same signal input terminal depending on the actual situation.

[0055] It should be noted that there is a potential difference between the first electrode and the second electrode of the light-emitting element 20 (i.e., a potential difference between the first pad 11 and the second pad 12), and this potential difference is related to the amount of charge on the first pad 11 and the second pad 12. Since the first pad 11 is connected to the signal transmission line 40, the amount of charge on the first pad 11 is reduced due to the influence of the signal transmission line 40, which leads to an increase in the potential difference between the first pad 11 and the second pad 12. Therefore, it is possible to adjust the resistance of the signal transmission line 40 to regulate its influence on the amount of charge on the first pad 11, thereby reducing the potential difference between the first pad 11 and the second pad 12 and controlling the potential difference within a suitable range.

[0056] For example, by adjusting the resistance of the signal transmission line 40, the potential difference is controlled between a basic threshold and a target threshold. The basic threshold is greater than or equal to the turn-on voltage of the light-emitting element 20, and the target threshold is a critical potential difference value that prevents the first pad 11 from bubbling 30. For example, the resistance of the signal transmission line 40 can be set to approximately 0.45 ohms, such as between 0.25 ohms and 0.65 ohms, specifically 0.25 ohms, 0.3 ohms, 0.35 ohms, 0.4 ohms, 0.45 ohms, 0.5 ohms, 0.55 ohms, 0.6 ohms, and 0.65 ohms. For example, the potential difference x between the first pad 11 and the second pad 12 can be set to satisfy 2.5V < x ≤ 7.8V, but it is not limited to this. The values ​​of x include: 3V, 3.5V, 4V, 4.5V, 5V, 5.5V, 6V, 6.5V, 7V, 7.5V, etc.

[0057] For example, the potential difference between the first pad 11 and the second pad 12 can be reduced by adjusting at least one of the length, width and thickness of the signal transmission line 40, such as reducing the width of the signal transmission line 40 and increasing the resistance of the signal transmission line 40, so that the difference in the performance of the Ni / Cu interface layer caused by the potential difference can be improved in the ENIG process.

[0058] According to the specific structure of the circuit board described above, the driving component in the circuit board provided in this disclosure includes: at least one set of pad groups 10 and at least one signal transmission line 40. The pad group 10 includes a first sub-pad group 101, which includes a first pad 11 and a second pad 12 that are independent of each other. The signal transmission line 40 is connected to the corresponding signal input terminal and the first pad 11 in the corresponding pad group 10. Since the charges on the first pad 11 and the second pad 12 affect the potential difference between the first pad 11 and the second pad 12 after the light-emitting element 20 is connected, and the resistance of the signal transmission line 40 connected to the first pad 11 affects the charge on the first pad 11, in the circuit board provided in this embodiment, by reasonably setting the resistance value of the signal transmission line 40, the resistance of the signal transmission line 40 can satisfy that the potential difference between the first pad 11 and the second pad 12 is less than a target threshold. The target threshold is a critical value of potential difference that can satisfy the first pad 11 without bubbling 30, thereby solving the problem that when the device is soldered onto the pad, the pad is prone to bubbling 30, which affects the yield of the display product.

[0059] Please refer to Figures 2 to 5. In some embodiments, the driving component includes:

[0060] At least two groups of pads, group 10;

[0061] At least two signal transmission lines 40, each signal transmission line 40 including a bus 401 and a branch line 402 connected to each other, the at least two signal transmission lines 40 multiplex the same bus 401, the bus 401 is connected to the signal input terminal, and the branch line 402 is connected to the first pad 11 in the corresponding pad group 10.

[0062] The resistance of the branch line 402 satisfies the condition that the potential difference between the first pad 11 and the second pad 12 in its corresponding pad group 10 is less than the target threshold.

[0063] For example, the bus 401 and the branch line 402 included in the signal transmission line 40 can be formed as an integral structure or set in different layers, and are electrically connected through vias.

[0064] For example, the line width of the bus 401 is greater than the line width of the branch line 402. Each signal transmission line 40 belonging to the same driving component shares the same bus 401 and receives the signal provided by the signal input terminal through the bus 401.

[0065] For example, each signal transmission line 40 belonging to the same driving component shares the same bus 401, therefore the bus 401 has the same effect on the charge of the first pads 11 connected to each signal transmission line 40. Furthermore, since the bus 401 is used to provide signals to multiple first pads 11 belonging to the same driving component, the bus 401 needs to maintain a certain linewidth.

[0066] The above-mentioned configuration allows at least two signal transmission lines 40 to reuse the same bus 401 and connect to the signal input terminal through the same bus 401. This helps to reduce the overall layout space occupied by the at least two signal transmission lines 40 and reduce the layout difficulty of the drive components within the limited layout space.

[0067] In the circuit board provided in the above embodiment, by reasonably setting the resistance value of the branch line 402, the resistance of the signal transmission line 40 can satisfy the requirement that the potential difference between the first pad 11 and the second pad 12 is less than a target threshold. The target threshold is a critical value of potential difference that can ensure that the first pad 11 does not bubble 30. This solves the problem that when the device is soldered onto the pad, the pad is prone to bubbling 30, which affects the yield of the display product.

[0068] As shown in Figure 2, in some embodiments, in the same group of drive components, at least a portion of the first sub-pad group 101 includes the first pad 11 to which the branch line 402 is connected has equal resistance.

[0069] For example, the resistance of the branch line 402 connected to the first pad 11 of each pad group 10 in the same group of drive components is equal.

[0070] For example, the resistance of the branch line 402 can be adjusted by changing at least one of the line length, line width, and thickness of the branch line 402, thereby ensuring that the resistance of each signal transmission line 40 remains consistent.

[0071] The above configuration ensures that the resistance of the signal transmission lines 40 connected to each pad group 10 remains consistent, and that the current flowing into each pad group 10 is consistent. This ensures that the IR drop of the pad group 10 at the near end and the far end of the bonding area (i.e., the area where the signal input terminal is located) remains consistent, ensuring that the brightness of the light-emitting elements 20 at the far end and the near end is the same, making the brightness of the light-emitting elements 20 on the entire circuit board more uniform.

[0072] As shown in Figure 2, in some embodiments, in the same group of drive components, at least a portion of the first sub-pad group 101 includes the same thickness of the branch lines 402 connected to the first pad 11, and at least a portion of the first sub-pad group 101 includes the same ratio of line length to line width of the branch lines 402 connected to the first pad 11.

[0073] By setting the line length to line width ratio of the branch lines 402 connected to the first pads 11 of at least some of the pad groups 10 to be the same, it is possible to achieve that the branch lines 402 connected to the first pads 11 of at least some of the pad groups 10 have the same resistance in the same group of driving components, so that the current flowing into each pad group 10 is consistent. This ensures that the IR drop of the pad groups 10 at the near end and the far end of the bonding area (i.e., the area where the signal input terminal is located) is consistent, ensuring that the brightness of the light-emitting elements 20 at the far end and the near end is the same, making the brightness of the light-emitting elements 20 on the entire circuit board more uniform.

[0074] As shown in Figures 3 to 5, in some embodiments, the branch line 402 includes at least two line segments 402a connected in sequence, with adjacent line segments 402a having different extension directions. The starting line segment of the at least two line segments 402a is connected to the corresponding bus 401, and the ending line segment of the at least two line segments 402a is connected to the first pad 11 in the corresponding first sub-pad group 101. The resistance of the branch line 402 is the sum of the resistances of each of its included line segments 402a.

[0075] For example, the at least two line segments 402a are arranged in the same layer and with the same material; or, of the at least two line segments 402a, a portion of the line segments 402a and another portion of the line segments 402a are arranged in different layers.

[0076] The aforementioned branch line 402 comprises at least two sequentially connected line segments 402a. The adjacent line segments 402a extend in different directions, resulting in a more diverse overall structure for the branch line 402. This allows for more flexible layout options within a limited space, reducing wiring difficulty. Furthermore, the resistance value of the branch line 402 can be adjusted by changing the width or length of any line segment 402a.

[0077] As shown in Figure 3, in some embodiments, in the same group of driving components, the at least two groups of pads 10 are arranged sequentially along a first direction; the circuit board includes multiple groups of the driving components, which are arranged along a second direction, the second direction intersecting the first direction;

[0078] The circuit board further includes a power supply circuit located on one side of the plurality of drive components along the first direction, and the power supply circuit includes a plurality of signal input terminals.

[0079] For example, the first direction includes the longitudinal direction, and the second direction includes the transverse direction, but is not limited thereto.

[0080] For example, the power supply circuit further includes a driver chip bonded to the signal input terminal, the driver chip being used to provide a signal to the signal input terminal.

[0081] As shown in Figures 6, 9, and 10, in some embodiments, in at least one of the starting drive component Q1, the ending drive component, and the intermediate drive component Qz included in the plurality of drive components, the line length of the branch line 402 coupled to each of the first sub-pad groups 101 along the first direction increases sequentially, and the line width of the branch line 402 coupled to each of the first sub-pad groups 101 along the first direction increases sequentially.

[0082] Along the first direction, from near the signal input terminal to away from the signal input terminal, the driving components in the start driving component Q1 and / or end driving component are arranged sequentially; along the first direction, from near the signal input terminal to away from the signal input terminal, the line length of the branch line 402 coupled to each pad group 10 increases sequentially, and the line width of the branch line 402 coupled to each pad group 10 increases sequentially along the first direction, thereby ensuring that in the same group of driving components, the ratio of line length to line width of the branch line 402 connected to the first pad 11 of each pad group 10 is the same, and the branch line 402 connected to the first pad 11 of each pad group 10 has the same resistance.

[0083] The above-mentioned configuration ensures that the length of the branch lines 402 coupled to each driving component along the first direction increases sequentially, and the line width of the branch lines 402 coupled to each pad group 10 along the first direction increases sequentially. This enables the branch lines 402 connected to the first pad 11 of each pad group 10 to have the same resistance in the starting driving component Q1 and / or the ending driving component, thereby making the current flowing into each pad group 10 consistent. This ensures that the IR drop of the pad group 10 at the near end and the far end of the bonding area can be kept consistent, ensuring that the brightness of the light-emitting element 20 at the far end and the near end is the same, making the brightness of the light-emitting element 20 on the entire circuit board more uniform.

[0084] In some embodiments, among at least one of the starting drive component Q1, the ending drive component, and the intermediate drive component Qz included in the plurality of drive components, the line length of the branch line 402 coupled to each of the first sub-pad groups 101 along the first direction increases proportionally, and the line width of the branch line 402 coupled to each of the first sub-pad groups 101 along the first direction increases proportionally.

[0085] For example, the resistance calculation formula is: R = ρL / S = ρL / (t*d), where L is the line length, t is the cross-sectional thickness of branch line 402, and d is the cross-sectional width, i.e., the line width. Taking a drive component including 36 groups of solder pads 10 as an example, it satisfies: ρL1 / (t*d1) = ρL2 / (t*d2) = ρL3 / (t*d3) = ... = ρL36 / (t*d36), where L2 = 2L1, L3 = 3L1, L4 = 4L1, L5 = 5L1, and so on, L36 = 36L1; d2 = 2d1, d3 = 3d1, d4 = 4d1, d5 = 5d1, and so on, d36 = 36d1. Given: d1+d2+d3+…+d36=d1+2d1+3d1+…+36d1=d, where d can be obtained from the wiring space, so we can calculate d1=d / 666.

[0086] The above-mentioned configuration ensures that the length of the branch lines 402 coupled to each driving component along the first direction increases proportionally, and the line width of the branch lines 402 coupled to each pad group 10 along the first direction increases proportionally. This enables the branch lines 402 connected to the first pad 11 of each pad group 10 in the starting driving component Q1 and / or the ending driving component to have the same resistance, thereby making the current flowing into each pad group 10 consistent. This ensures that the IR drop of the pad group 10 at the near end and far end of the bonding area remains consistent, ensuring that the brightness of the light-emitting element 20 at the far end and near end is the same, making the brightness of the light-emitting element 20 on the entire circuit board more uniform.

[0087] As shown in Figures 3 to 5 and Figure 7, in some embodiments, the plurality of driving components further includes a plurality of transition driving components Qg, a portion of which is located between the starting driving component Q1 and the intermediate driving component Qz, and another portion of which is located between the intermediate driving component Qz and the ending driving component.

[0088] In the transition drive component Qg, at least two adjacent first sub-pad groups 101 include first pads 11 connected to signal transmission lines 40 that multiplex at least a portion of the same branch line 402.

[0089] As shown in Figure 7, in the third row of pad groups 10, the first pad group and the second pad group reuse at least a portion of the same branch line 402.

[0090] Due to the limited wiring space on the circuit board, when the circuit board includes multiple driving components, at least a portion of the bus 401 in each driving component needs to be arranged sequentially along the first direction and partially staggered along the second direction. In order to ensure the uniformity of the layout of the pad groups 10, the pad groups 10 in the circuit board are arranged in an array. Thus, in the transition component, some pad groups 10 are located on the first side of the bus 401 they include, and another portion of pad groups 10 are located on the second side of the bus 401 they include. The first side and the second side are opposite to each other along the first direction, and the first side is closer to the signal input terminal. Since there are fewer pad groups 10 on the first side and the wiring space is smaller, it is considered to set the signal transmission line 40 connected to the first pad 11 of at least two groups of pad groups 10 located on the first side in the transition driving component Qg to reuse at least a portion of the same branch line 402, thereby overcoming the problem of high wiring difficulty caused by limited wiring space.

[0091] In some embodiments, in the intermediate drive component Qz and the multiple sets of transition drive components Qg, in at least two partially adjacent sets of drive components, each of the signal transmission lines 40 multiplexes the same bus 401.

[0092] As shown in Figure 7, adjacent first and second groups of driver components share the same bus 401. Adjacent third and fourth groups of driver components also share the same bus 401.

[0093] The above setup further overcomes the problem of high wiring difficulty caused by limited wiring space, effectively reducing the wiring difficulty of the circuit board.

[0094] As shown in Figures 3 to 10, in some embodiments, the pad group 10 further includes at least one second sub-pad group 102, the second sub-pad group 102 including a third pad and a fourth pad that are independent of each other; the second sub-pad group 102 is used to connect the corresponding light-emitting element 20, the third pad is used to connect the first electrode of the light-emitting element 20, and the fourth pad is used to connect the second electrode of the light-emitting element 20.

[0095] When the pad group 10 includes a second sub-pad group 102, the second pad 12 is connected to the third pad in the second sub-pad group 102; the fourth pad in the second sub-pad group 102 can be directly coupled to the corresponding N-pole signal input terminal (located in the bonding area 50).

[0096] When the pad group 10 includes at least two second sub-pad groups 102, the second pad 12 is connected to the third pad in the first second sub-pad group 102. The at least two second sub-pad groups 102 are connected in series. In the two connected second sub-pad groups 102, the fourth pad of one second pad group 10 is connected to the third pad of the other second pad group 10. The fourth pad in the last second sub-pad group 102 of the at least two second sub-pad groups 102 can be directly coupled to the corresponding N-pole signal input terminal.

[0097] It should be noted that in Figures 3, 5, 7, 8, and 10, the dashed lines connecting the sub-pad groups represent conductive connections, which are disposed on a different layer from the bus 401 and branch line 402 in the figures. For example, the conductive connections may be formed using one layer of copper, while the bus 401 and branch line 402 may be formed using another layer of copper, but this is not a limitation. It is worth noting that the branch line 402 in Figures 3, 4, 6, 7, 8, and 9 has a certain line width; the differences in line width are not illustrated in the figures.

[0098] For example, the pad group includes three second sub-pad groups; the fourth pad in the first second sub-pad group is connected to the third pad in the second second sub-pad group, and the fourth pad in the second second sub-pad group is connected to the third pad in the third second sub-pad group. The fourth pad in the third second sub-pad group can be directly coupled to the corresponding N-pole signal input terminal.

[0099] For example, the circuit board includes a first metal layer and a second metal layer. The first metal layer can be used to form the bus and at least part of the branch line, and the second metal layer can also be used to form at least part of the branch line. The second metal layer can also be used to form a conductive connection between two pads, but is not limited thereto.

[0100] This disclosure also provides a backlight structure, including the circuit board provided in the above embodiments; the backlight structure further includes a light-emitting element, the first electrode of the light-emitting element is connected to a first pad in a corresponding pad group in the circuit board, and the second electrode of the light-emitting element is connected to a second pad in the corresponding pad group.

[0101] For example, the circuit board includes multiple driving components, and the backlight structure includes multiple light-emitting elements, which correspond one-to-one with the pad groups in the circuit board, but are not limited thereto.

[0102] For example, the backlight structure can be applied in a display device to provide backlighting for the display device. For instance, the display device includes, but is not limited to, a liquid crystal display.

[0103] In the circuit board provided in the above embodiments, the driving component includes: at least one set of pads and at least one signal transmission line. The pads include a first sub-pad group, which includes independent first and second pads. The signal transmission line is connected to a corresponding signal input terminal and a corresponding first pad in the pad group. Since the charge on the first and second pads affects the potential difference between them after connecting the light-emitting element, and the resistance of the signal transmission line connected to the first pad affects the charge on the first pad, the circuit board provided in the above embodiments, by reasonably setting the resistance value of the signal transmission line, ensures that the potential difference between the first and second pads is less than a target threshold. This target threshold is a critical potential difference value that prevents the first pad from bubbling, thus solving the problem that bubbling easily occurs on the pads when soldering devices onto them, thereby affecting the yield of the display product.

[0104] Therefore, the backlight structure provided in this embodiment of the present disclosure, when including the above-mentioned circuit board, also has the above-mentioned beneficial effects, which will not be repeated here.

[0105] This disclosure also provides a display panel, including the circuit board provided in the above embodiments; the display panel further includes a light-emitting element, the first electrode of the light-emitting element is connected to a first pad in a corresponding pad group in the circuit board, and the second electrode of the light-emitting element is connected to a second pad in the corresponding pad group.

[0106] For example, the circuit board includes multiple driving components, and the display panel includes multiple light-emitting elements, which correspond one-to-one with the pad groups in the circuit board, but are not limited thereto.

[0107] For example, the circuit board can be applied to a display panel, and the circuit board is combined with the light-emitting element to realize the display function of the display panel.

[0108] In the circuit board provided in the above embodiments, the driving component includes: at least one set of pads and at least one signal transmission line. The pads include a first sub-pad group, which includes independent first and second pads. The signal transmission line is connected to a corresponding signal input terminal and a corresponding first pad in the pad group. Since the charge on the first and second pads affects the potential difference between them after connecting the light-emitting element, and the resistance of the signal transmission line connected to the first pad affects the charge on the first pad, the circuit board provided in the above embodiments, by reasonably setting the resistance value of the signal transmission line, ensures that the potential difference between the first and second pads is less than a target threshold. This target threshold is a critical potential difference value that prevents the first pad from bubbling, thus solving the problem that bubbling easily occurs on the pads when soldering devices onto them, thereby affecting the yield of the display product.

[0109] Therefore, the display panel provided in this embodiment of the present disclosure, when including the above-mentioned circuit board, also has the above-mentioned beneficial effects, which will not be repeated here.

[0110] This disclosure also provides a display device, including the display panel provided in the above embodiments.

[0111] Therefore, the display device provided in this embodiment of the present disclosure, when including the above-described display panel, also has the above-described beneficial effects, which will not be repeated here.

[0112] It should be noted that the signal line extending in a certain direction means that the signal line includes a main part and a secondary part connected to the main part. The main part is a line, line segment, or strip-shaped body. The main part extends in a certain direction, and the length of the main part extending in a certain direction is greater than the length of the secondary part extending in other directions.

[0113] It should be noted that, in the embodiments of this disclosure, "same layer" can refer to film layers located on the same structural layer. Alternatively, for example, film layers located on the same layer can be layer structures formed by using the same film deposition process to form a specific pattern, and then patterning the film layer using the same photomask through a single patterning process. Depending on the specific pattern, the single patterning process may include multiple exposure, development, or etching processes, and the specific pattern in the formed layer structure can be continuous or discontinuous. These specific patterns may also be at different heights or have different thicknesses.

[0114] In the various method embodiments of this disclosure, the sequence numbers of each step are not intended to limit the order of the steps. For those skilled in the art, any changes in the order of the steps are within the scope of protection of this disclosure without any creative effort.

[0115] It should be noted that the various embodiments in this specification are described in a progressive manner, and the same or similar parts between the various embodiments can be referred to mutually. Each embodiment focuses on describing the differences from other embodiments. In particular, the method embodiments are basically similar to the product embodiments, so the description is relatively simple, and the relevant parts can be referred to the description of the product embodiments.

[0116] Unless otherwise defined, the technical or scientific terms used in this disclosure shall have the ordinary meaning understood by one of ordinary skill in the art to which this disclosure pertains. The terms “first,” “second,” and similar terms used in this disclosure do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as “comprising” or “including” mean that the element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, without excluding other elements or objects. Terms such as “connection,” “coupled,” or “linked” are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as “upper,” “lower,” “left,” and “right” are used only to indicate relative positional relationships, and these relative positional relationships may change accordingly when the absolute position of the described objects changes.

[0117] It is understandable that when a component such as a layer, film, region, or substrate is referred to as being "above" or "below" another component, the component may be "directly" located "above" or "below" the other component, or there may be intermediate components present.

[0118] In the description of the above embodiments, specific features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments or examples.

[0119] The above description is merely a specific embodiment of this disclosure, but the scope of protection of this disclosure is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this disclosure should be included within the scope of protection of this disclosure. Therefore, the scope of protection of this disclosure should be determined by the scope of the claims.

Claims

1. A circuit board, comprising at least one driving assembly, the driving assembly comprising: at least one pad group, the pad group comprising a first sub-pad group, the first sub-pad group comprising a first pad and a second pad independent of each other, the pad group being configured to connect a corresponding light emitting element, the first pad being configured to connect a first electrode of the light emitting element, the second pad being configured to connect a second electrode of the light emitting element; and at least one signal transmission line, the signal transmission line being connected to a corresponding signal input and a corresponding first pad in the first sub-pad group, respectively, the signal transmission line having a resistance such that a potential difference between the first pad and the second pad is less than a target threshold. The driving assembly comprises: at least two pad groups; and at least two signal transmission lines, the signal transmission lines comprising a bus and a branch connected in series, the at least two signal transmission lines multiplexing the same bus, the bus being connected to the signal input, the branch being connected to the first pad in the corresponding pad group, the branch having a resistance such that a potential difference between the first pad and the second pad in the corresponding pad group is less than the target threshold. In the same driving assembly, resistances of the branches connected to the first pads in at least some of the first sub-pad groups are equal.

2. The circuit board of claim 1, wherein, In the same driving assembly, thicknesses of the branches connected to the first pads in at least some of the first sub-pad groups are equal, and ratios of lengths to widths of the branches connected to the first pads in at least some of the first sub-pad groups are equal. The branch comprises at least two line segments connected in series, adjacent line segments having different extension directions, a starting line segment being connected to the corresponding bus, and an ending line segment being connected to the first pad in the corresponding first sub-pad group, the resistance of the branch being a sum of resistances of the line segments. The at least two line segments are arranged in the same layer and are made of the same material, or a part of the at least two line segments are arranged in different layers from another part of the at least two line segments. In the same driving assembly, the at least two pad groups are arranged in a first direction in sequence, and the circuit board comprises a plurality of the driving assemblies arranged in a second direction, the second direction intersecting the first direction.

3. The circuit board of claim 2, wherein, The circuit board further comprises a power supply circuit, the power supply circuit being located on one side of the plurality of the driving assemblies in the first direction, and the power supply circuit comprising a plurality of the signal inputs.

4. The circuit board of claim 3, wherein, In at least one of a starting driving assembly, an ending driving assembly and an intermediate driving assembly included in the plurality of the driving assemblies, lengths of the branches coupled to the first sub-pad groups in the first direction increase in sequence, and widths of the branches coupled to the first sub-pad groups in the first direction increase in sequence.

5. The circuit board of claim 3, wherein, In at least one of a starting driving assembly, an ending driving assembly and an intermediate driving assembly included in the plurality of the driving assemblies, lengths of the branches coupled to the first sub-pad groups in the first direction increase in equal proportions, and widths of the branches coupled to the first sub-pad groups in the first direction increase in equal proportions.

6. The circuit board of claim 4, wherein, ​ 7. The circuit board according to any one of claims 2 to 6, wherein ​ ​ 8. The circuit board of claim 7, wherein, ​ 9. The circuit board of claim 8, wherein, ​ 10. The circuit board of claim 8, wherein, The plurality of driving assemblies further comprises a plurality of transition driving assemblies, some of which are located between the initial driving assembly and the intermediate driving assembly, and some of which are located between the intermediate driving assembly and the terminal driving assembly; In the transition driving assembly, at least two adjacent first sub-pad groups comprise first pads connected to at least part of the same branch of the signal transmission line.

11. The circuit board of claim 10, wherein, In the intermediate driving assembly and the plurality of transition driving assemblies, at least part of the adjacent driving assemblies each comprise a signal transmission line multiplexing the same bus line.

12. The circuit board according to claim 1, wherein, The pad group further comprises at least one second sub-pad group, which comprises third and fourth pads independent of each other; the second sub-pad group is used to connect a corresponding light emitting element, the third pad is used to connect a first electrode of the light emitting element, and the fourth pad is used to connect a second electrode of the light emitting element. In the case where the pad group comprises one second sub-pad group, the second pad is connected to the third pad in the second sub-pad group. In the case where the pad group comprises at least two second sub-pad groups, the second pad is connected to the third pad in the first second sub-pad group, and the at least two second sub-pad groups are connected in series; in the two connected second sub-pad groups, the fourth pad of one second sub-pad group is connected to the third pad of the other second sub-pad group.

13. The circuit board of claim 12, wherein, The pad group comprises three second sub-pad groups; the fourth pad in the first second sub-pad group is connected to the third pad in the second second sub-pad group, and the fourth pad in the second second sub-pad group is connected to the third pad in the third second sub-pad group.

14. A backlight structure comprising the circuit board according to any one of claims 1-13; the backlight structure further comprises a light emitting element, a first electrode of the light emitting element is connected to the first pad in the corresponding pad group of the circuit board, and a second electrode of the light emitting element is connected to the second pad in the corresponding pad group.

15. A display panel comprising the circuit board according to any one of claims 1-13; the display panel further comprises a light emitting element, a first electrode of the light emitting element is connected to the first pad in the corresponding pad group of the circuit board, and a second electrode of the light emitting element is connected to the second pad in the corresponding pad group.

Images