Circuit board and display device

Abstract

The present disclosure relates to a circuit board. The circuit board comprises pads and a circuit board body; the circuit board body comprises at least two thermally conductive layers; first conduction parts are each connected to the corresponding pad and the corresponding thermally conductive layer, respectively; and second conduction parts are each connected to two adjacent thermally conductive layers, respectively. The first conduction parts can transfer heat of the pads to the thermally conductive layers, and the second conduction parts can transfer heat between the thermally conductive layers, so that the heat can be longitudinally transferred between the thermally conductive layers; and at least two conduction parts among any two longitudinally adjacent conduction parts are staggered with each other, so that the heat is spread and dispersed by means of the thermally conductive layers, so as to effectively improve the transverse transfer and longitudinal transfer of the heat inside the circuit board, and prevent high temperature from being concentrated at a certain point, thereby avoiding the problem of yellowish display of a display panel caused by a high-temperature hot point. The present disclosure further provides a display device comprising the circuit board.

Description

Circuit board and display device

[0001] Cross-references

[0002] This disclosure claims priority to Chinese patent application number 202311634973.6, filed on November 30, 2023, entitled “Circuit Board and Display Device,” and the entire contents of which are incorporated herein by reference. Technical Field

[0003] The present disclosure relates to the field of display technology, and in particular to a circuit board and a display device. Background Art

[0004] In application scenarios such as aviation, automotive, and industrial control that require high reliability of display modules, the display modules are lit for a long time, resulting in high heat generation in the power management chip, MOS tube, and inductor on the circuit board.

[0005] Currently, the heat in the area where the pads of these components on the circuit board are located cannot be effectively diffused, which easily forms high-temperature hot spots. In severe cases, it causes display function problems such as yellowing of the display area of ​​the display panel, affecting the display effect.

[0006] It should be noted that the information disclosed in the above background technology section is only used to enhance the understanding of the background of the present disclosure, and therefore may include information that does not constitute prior art known to ordinary technicians in the field.

[0007] Summary of the Invention

[0008] The purpose of the present disclosure is to overcome the above-mentioned deficiencies of the prior art and to provide a circuit board and a display device.

[0009] According to one aspect of the present disclosure, a circuit board is provided, comprising a circuit board body and a binding layer, the binding layer being arranged on one side of the circuit board body, the binding layer comprising solder pads and leads, the solder pads being used to bind electronic components, the leads being connected to the solder pads and being used to transmit electrical signals to the solder pads or to transmit electrical signals from the solder pads to the interior of the circuit board; the circuit board body comprising at least two thermally conductive layers, an insulating layer being provided between the solder pads and the thermally conductive layers, and between two adjacent thermally conductive layers, the insulating layer being provided with vias, the vias being filled with conducting parts, the conducting parts located between the solder pads and the thermally conductive layers being a first conducting part, the first conducting part being connected to the solder pads and the thermally conductive layers, respectively; the conducting parts between the two adjacent thermally conductive layers being a second conducting part, the second conducting part being connected to the two adjacent thermally conductive layers, at least two of any two adjacent conducting parts in the longitudinal direction are staggered with each other, the longitudinal direction being the thickness direction of the circuit board body.

[0010] In one embodiment of the present disclosure, the pad includes a first pad, the lead includes a reference signal line, the reference signal line is connected to the first pad, and is used to input a reference signal to the first pad, the thermal conductive layer includes a first sub-thermal conductive layer, a first via is provided between the first pad and the first sub-thermal conductive layer, the first via is filled with a first conductive portion, and the first conductive portion is respectively connected to the first pad and the first sub-thermal conductive layer.

[0011] In one embodiment of the present disclosure, the pad includes a second pad, the lead includes a high-level signal line, the high-level signal line is connected to the second pad, the high-level signal line is used to input a high-level signal to the second pad, the thermal conductive layer includes a second sub-thermal conductive layer, the second sub-thermal conductive layer and the first sub-thermal conductive layer are insulated from each other, a first via is provided between the second pad and the second sub-thermal conductive layer, the first via is filled with a first conductive portion, and the first conductive portion is respectively connected to the second pad and the second sub-thermal conductive layer.

[0012] In one embodiment of the present disclosure, at least two first conduction parts are provided between the solder pad and the heat-conducting layer, and the same number of second conduction parts as the first conduction parts are provided between every two adjacent heat-conducting layers. The first conduction parts and the second conduction parts closest to the first conduction parts are located on the same straight line along the longitudinal direction, and the longitudinal direction is the thickness direction of the circuit board body.

[0013] In one embodiment of the present disclosure, at least one first conduction portion is provided between the solder pad and the heat-conducting layer, and two second conduction portions are provided between two adjacent heat-conducting layers. The two second conduction portions are located on both sides of the first conduction portion, and the distance between the two second conduction portions gradually increases in the direction away from the solder pad.

[0014] In one embodiment of the present disclosure, the heat conducting layer farthest from the solder pad is the first heat conducting layer. A first hollow portion is provided on the first heat conducting layer, and the orthographic projection of the solder pad on the first heat conducting layer is located in the first hollow portion.

[0015] In one embodiment of the present disclosure, the remaining heat-conducting layers are second heat-conducting layers, and the second conducting portion between the first heat-conducting layer and the adjacent second heat-conducting layer is provided on both sides of the first hollow portion.

[0016] In one embodiment of the present disclosure, a third via is provided between the second vias of at least part of the insulating layer, the third via is filled with a third conducting portion, the third conducting portion is respectively connected to two adjacent thermal conductive layers, and the third conducting portion is provided between two second conducting portions of the same insulating layer.

[0017] In one embodiment of the present disclosure, the number of the third conducting portions gradually increases in a direction away from the pad.

[0018] In one embodiment of the present disclosure, in the same insulating layer, the distance between any two adjacent conductive portions is equal, and the distance between adjacent conductive portions gradually decreases in a direction away from the pad.

[0019] In one embodiment of the present disclosure, the number of third conducting parts is alternately arranged in even and odd numbers, the heat conducting layer farthest from the pad is provided with an even number of third conducting parts, and a first hollow part is provided between the two third conducting parts closest to the straight line distance of the first conducting part.

[0020] In one embodiment of the present disclosure, the cross-sectional areas of the first conductive portion and the second conductive portion gradually increase from the middle portion toward both ends thereof.

[0021] According to another aspect of the present disclosure, a display device is provided, comprising a display module and the circuit board provided in one aspect of the present disclosure, wherein the display module comprises a display panel, a middle frame, and a heat dissipation mechanism; the circuit board is connected to the display panel, and the circuit board extends laterally beyond the edge of at least one side of the display panel to form an exposed portion, and the exposed portion is connected to the middle frame and / or the heat dissipation mechanism.

[0022] In one embodiment of the present disclosure, the heat-conducting layer of the circuit board extends laterally beyond the edges of both sides of the display panel to form two exposed portions, and both exposed portions are connected to the middle frame and / or the heat dissipation mechanism.

[0023] In one embodiment of the present disclosure, the heat-conducting layer closest to the display panel is the first heat-conducting layer, the first heat-conducting layer is provided with a second hollow portion, the orthographic projection of the display panel on the first heat-conducting layer is located in the second hollow portion, and the exposed portions are located on both sides of the second hollow portion.

[0024] The circuit board disclosed herein includes a solder pad and a circuit board body. The circuit board body includes at least two thermally conductive layers, wherein a first conductive portion is connected to the solder pad and the thermally conductive layer, respectively, and a second conductive portion is connected to two adjacent thermally conductive layers. The first conductive portion transfers heat from the solder pad to the thermally conductive layer, and the second conductive portion transfers heat between the thermally conductive layers, thereby achieving longitudinal heat transfer between the thermally conductive layers. At least two of any two longitudinally adjacent conductive portions are staggered, allowing heat to spread and disperse through the thermally conductive layers, thereby effectively improving both lateral and longitudinal heat transfer within the circuit board, preventing high temperatures from concentrating at a single point, and thus preventing the problem of high-temperature hot spots causing yellowing of the display panel.

[0025] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The accompanying drawings are incorporated into and constitute a part of the specification, illustrate embodiments consistent with the present disclosure, and together with the specification, are used to explain the principles of the present disclosure. Obviously, the drawings described below are only some embodiments of the present disclosure, and those skilled in the art can derive other drawings based on these drawings without inventive effort.

[0027] FIG1 is a plan view of a circuit board according to an embodiment of the present disclosure, in which a via hole is provided when a jumper is formed between layers, a conductive portion is provided in the via hole, and two conductive layers are connected.

[0028] FIG2 is a schematic cross-sectional view of the circuit board according to an embodiment of the present disclosure when the first conducting portion and the second conducting portion of different insulating layers are both located on the same straight line in the longitudinal direction.

[0029] FIG3 is a plan view of a circuit board according to an embodiment of the present disclosure when a conductive portion is provided to connect a pad and a heat-conducting layer and adjacent heat-conducting layers.

[0030] FIG4 is a schematic cross-sectional view of the circuit board according to an embodiment of the present disclosure when two first conducting portions and two second conducting portions of each insulating layer form two conducting lines parallel to each other.

[0031] 5 is a schematic cross-sectional view of a circuit board according to an embodiment of the present disclosure, wherein the second conducting portions between the first heat conducting layer and the adjacent second heat conducting layer are provided on both sides of the first hollow portion, and the remaining second conducting portions and the first conducting portions are located on the same straight line in the longitudinal direction.

[0032] FIG6 is a schematic cross-sectional view of the circuit board according to an embodiment of the present disclosure when the distance between the two second conducting portions gradually increases in a direction away from the solder pad.

[0033] FIG7 is a schematic cross-sectional view of the circuit board according to an embodiment of the present disclosure when a third heat conducting portion is disposed between two second heat conducting portions.

[0034] FIG8 is a plan view of a circuit board according to an embodiment of the present disclosure, in which a third conducting portion is disposed between two second heat conducting portions and a first hollow portion is disposed on the first heat conducting layer.

[0035] FIG9 is a schematic cross-sectional view of a circuit board according to an embodiment of the present disclosure, wherein the cross-sectional area of ​​the conductive portion is configured to gradually increase from the middle thereof toward both ends thereof.

[0036] FIG10 is a plan view of the circuit board according to an embodiment of the present disclosure, when an exposed portion is formed along an edge of the circuit board extending laterally beyond one side of the display panel.

[0037] FIG11 is a plan view of the circuit board according to an embodiment of the present disclosure, when the circuit board extends beyond the edges on both sides of the display panel in the transverse direction to form two exposed portions.

[0038] FIG12 is a cross-sectional view taken along line AA of FIG11 . DETAILED DESCRIPTION

[0039] Example embodiments will now be described more fully with reference to the accompanying drawings. However, the example embodiments can be implemented in many forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete and will fully convey the concepts of the example embodiments to those skilled in the art. Like reference numerals in the figures represent identical or similar structures, and thus their detailed descriptions will be omitted. Furthermore, the figures are merely schematic illustrations of the present disclosure and are not necessarily drawn to scale.

[0040] Although relative terms such as "upper" and "lower" are used in this specification to describe the relationship of one illustrated component to another, these terms are used herein for convenience only, such as in accordance with the orientation of the illustrations in the accompanying drawings. It will be understood that if the illustrated device were flipped upside down, the component described as "upper" would become the component "lower." When a structure is referred to as "on" another structure, this may mean that the structure is integrally formed with the other structure, that the structure is "directly" disposed on the other structure, or that the structure is "indirectly" disposed on the other structure via the other structure.

[0041] The terms "a", "an", "the", "said" and "at least one" are used to indicate the presence of one or more elements / components / etc.; the terms "including" and "having" are used to express open-ended inclusion and mean that additional elements / components / etc. may be present in addition to the listed elements / components / etc.; the terms "first", "second" and "third" etc. are used only as labels and are not intended to limit the quantity of their objects.

[0042] OLED display modules have gradually expanded from consumer electronics products to application scenarios such as aviation, automotive, and industrial control. The typical characteristics of these scenarios are that the display modules have a long lighting time and a relatively harsh operating environment, especially in a high-temperature environment. This causes the power management chip 20, inductor, and MOS on the circuit board 100 to generate high heat, resulting in the heat in the area where the pads of these electronic components are located being unable to effectively diffuse, easily forming high-temperature hot spots. In severe cases, this causes display function problems such as yellowing of the display area of ​​the display panel, seriously affecting the user experience.

[0043] As shown in Figure 1, the binding layer 14 includes a pad 141 and a lead 142. The layout design of the pad 141 and the lead 142 does not take into account the heat dissipation problem of the heat-generating device pad 141. The via 121 is only set when it is necessary to jump the lead 142 between layers. The conductive part 13 is set in the via 121 to connect the two conductive layers. As a result, the heat on the pad 141 cannot be effectively diffused. The maximum temperature in the pad 141 area can reach 58°C, while the average temperature in other areas is 40°C. If the heat transfer capacity inside the circuit board 100 can be improved and the heat can be evenly distributed on the circuit board 100, the temperature of the highest point on the circuit board 100 will inevitably be greatly reduced, thereby avoiding the problem of yellowing of the display area of ​​the display panel.

[0044] Based on this, the embodiment of the present disclosure provides a circuit board 100. As shown in Figures 2 to 12, the circuit board 100 includes a circuit board body 10 and a binding layer 14. The binding layer 14 is provided on one side of the circuit board body 10. The binding layer 14 includes a solder pad 141 and a lead. The solder pad 141 is used to bind electronic components. The lead is connected to the solder pad 141 and is used to transmit electrical signals to the solder pad 141 or transmit electrical signals from the solder pad 141 to the inside of the circuit board. The circuit board body 10 includes at least two layers of heat-conducting layers 11. There is an insulating layer between the solder pad 141 and the heat-conducting layer 11, as well as between two adjacent layers of heat-conducting layers 11. The insulating layer 12 is provided with a via 121, and the via 121 is filled with a conducting portion 13. The conducting portion located between the solder pad 141 and the thermally conductive layer 11 is a first conducting portion 131, and the first conducting portion 131 is connected to the solder pad 141 and the thermally conductive layer 11 respectively; the conducting portion 13 between two adjacent thermally conductive layers 11 is a second conducting portion 132, and the second conducting portion 132 is connected to the two adjacent thermally conductive layers 11 respectively. At least two of any two adjacent conducting portions 13 in the longitudinal direction are staggered with each other, and the longitudinal direction is the thickness direction of the circuit board body 10.

[0045] The circuit board body 10 includes at least two thermally conductive layers 11. A first conductive portion 131 is connected to the solder pad 141 and the thermally conductive layer 11, respectively. A second conductive portion 132 is connected to two adjacent thermally conductive layers 11. The first conductive portion 131 transfers heat from the solder pad 141 to the thermally conductive layer 11, while the second conductive portion 132 transfers heat between the thermally conductive layers 11. This allows heat to be transferred longitudinally between the thermally conductive layers 11. At least two of any two longitudinally adjacent conductive portions 13 are staggered, allowing heat to spread and disperse through the thermally conductive layers 11. This effectively improves both lateral and longitudinal heat transfer within the circuit board 100, preventing high temperatures from concentrating at a single point and, consequently, preventing hot spots from causing yellowing on the display panel.

[0046] It should be noted that the pad 141 is part of the conductive circuit, and the first conductive part 131, the second conductive part 132 and each layer of the heat-conducting layer 11 only serve as the heat-conducting structure of the pad 141. They are disconnected from other leads and electronic components in the conductive circuit and do not form a loop.

[0047] The circuit board 100 according to the embodiment of the present disclosure will be described in detail below with reference to specific examples.

[0048] As shown in Figures 2 and 3, circuit board 100 includes a binding layer 14 and multiple thermally conductive layers 11 arranged sequentially along its thickness. Binding layer 14 includes a solder pad 141. An insulating layer 12 is provided between solder pad 141 and thermally conductive layer 11, and between two adjacent thermally conductive layers 11. The solder pad 141, thermally conductive layer 11, and adjacent insulating layers 12 are bonded to each other. Vias 121 are provided between solder pad 141 and thermally conductive layer 11, and between two adjacent thermally conductive layers 11. Conductive portions 13 are filled in vias 121, connecting solder pad 141 to thermally conductive layer 11 and to adjacent thermally conductive layers 11. Specifically, a first via is provided in the insulating layer 12 between the pad 141 and the thermal conductive layer 11, and the first conducting portion 131 is filled in the first via. The first conducting portion 131 is respectively connected to the pad 141 and the thermal conductive layer 11. A second via is provided in the insulating layer 12 between two adjacent thermal conductive layers 11, and the second conducting portion 132 is filled in the second via. The second conducting portion 132 is respectively connected to the two adjacent thermal conductive layers 11.

[0049] The pads 141 include a first pad 1411 and a second pad 1412. The leads include a reference signal line and a high-level signal line. The reference signal line is connected to the first pad 1411 and is used to input a reference signal to the first pad 1411. The high-level signal line is connected to the second pad 1412 and is used to input a high-level signal to the second pad 1412. The voltage of the high-level signal is greater than the voltage of the reference signal. The thermal conductive layer 11 includes a first sub-heat conductive layer 1101 and a second sub-heat conductive layer 1102. The second sub-heat conductive layer 1102 is insulated from the first sub-heat conductive layer 1101. The thermal conductive layer 11 can be provided as a single layer. The shape and size of the first sub-heat conductive layer 1101 complement the shape and size of the second sub-heat conductive layer 1102. In this embodiment, an opening is provided on the thermally conductive layer 11 to form a first thermally conductive sub-layer 1101, and a second thermally conductive sub-layer 1102 is provided in the opening. The shape and size of the second thermally conductive sub-layer 1102 can be the same as the shape and size of the second solder pad 1412. A gap is formed between the edge of the second thermally conductive sub-layer 1102 and the edge of the opening, and the insulating portion is filled in the gap.

[0050] As shown in Figure 3, a first via is provided between first pad 1411 and first thermal sub-layer 1101. First conductive portion 131 is filled in the first via, connecting first pad 1411 and first thermal sub-layer 1101, respectively. A first via is provided between second pad 1412 and second thermal sub-layer 1102. First conductive portion 131 is filled in the first via, connecting first pad 1412 and second thermal sub-layer 1102, respectively. First conductive portion 131 and second conductive portion 132 of different insulating layers 12 are all located on the same straight line along the longitudinal direction.

[0051] There are no specific requirements for the number of conducting portions 13 provided on each insulating layer 12; the specific number depends on the relative size of the area of ​​the solder pad 141 and the cross-sectional area of ​​the conducting portion 13. As shown in FIG4 , two first conducting portions 131 are provided between the first solder pad 1411 and the first thermally conductive sub-layer 1101. Between every two adjacent first thermally conductive sub-layers 1101, there are second conducting portions 132 equal in number to the first conducting portions 131. The two first conducting portions 131 and the two second conducting portions 132 of each insulating layer 12 form two parallel conducting lines. The orthographic projections of the second solder pad 1412 and the plurality of second thermally conductive sub-layers 1102 on the circuit board body 10 overlap. Two first conducting portions 131 are provided between the second solder pad 1412 and the second thermally conductive sub-layer 1102. Between every two adjacent second thermally conductive sub-layers 1102, there are second conducting portions 132 equal in number to the first conducting portions 131. The two first conducting portions 131 and the two second conducting portions 132 of each insulating layer 12 form two parallel conducting lines.

[0052] As shown in Figure 5, when the circuit board 100 is applied to a display module, the circuit board 100 is typically attached to a display panel, and therefore, it is also necessary to reduce heat conduction to the display area of ​​the display panel. The heat-conducting layer 11 farthest from the solder pad 141 is defined as the first heat-conducting layer 111, and the remaining heat-conducting layers 11 are defined as the second heat-conducting layer 112. The first heat-conducting layer 111 is provided with a first hollow portion 111, and the orthographic projection of the solder pad 141 on the first heat-conducting layer 111 is located within the first hollow portion 111. The portion of the first heat-conducting layer 111 located in the first hollow portion 111 is completely etched away to reduce heat conduction to the display area of ​​the display panel, further alleviating the yellowing problem of the display area of ​​the display panel.

[0053] For first solder pad 1411, first hollow portion 111 is provided on first sub-heat conducting layer 1101 of first thermally conductive layer 111, and the orthographic projection of first solder pad 1411 on first thermally conductive layer 111 is located within first hollow portion 111 of first sub-heat conducting layer 1101. For second solder pad 1412, first thermally conductive layer 111 is provided with two second sub-heat conducting layers 1102, first hollow portion 111 is provided between the two second sub-heat conducting layers 1102, and the orthographic projection of second solder pad 1412 on first thermally conductive layer 111 is located within first hollow portion 111 between the two second sub-heat conducting layers 1102. For both first solder pad 1411 and second solder pad 1412, second conductive portions 132 between the first thermally conductive layer 111 and the adjacent second thermally conductive layer 112 are provided on either side of first hollow portion 111, and the remaining second conductive portions 132 and first conductive portion 131 are longitudinally aligned on the same straight line. It should be noted that the longitudinal direction is the thickness direction of the circuit board 100 .

[0054] For the first and second conductive portions 131, 132 that are adjacent to each other and located on the same straight line, heat is transferred as follows: heat from the solder pad 141 is transferred to the first conductive portion 131, which then directly transfers the heat to the second conductive portion 132 closest to it. The closest second conductive portion 132 then transfers the heat to the other second conductive portions 132. This allows the heat from the solder pad 141 to be quickly transferred longitudinally to the side of the circuit board body 10 away from the solder pad 141. Clearly, this structure of the circuit board 100 exhibits improved longitudinal thermal conductivity. The longitudinal direction refers to the y-direction in the figure.

[0055] As shown in Figure 6, a first conducting portion 131 is disposed between the solder pad 141 and the thermally conductive layer 11, and two second conducting portions 132 are disposed between two adjacent thermally conductive layers 11. The two second conducting portions 132 are symmetrically located on either side of the first conducting portion 131, with the distance between the two second conducting portions 132 gradually increasing as they move away from the solder pad 141. Heat is conducted from the solder pad 141 to the first conducting portion 131, then laterally transferred from the first conducting portion 131 to the two second conducting portions 132 of the adjacent thermally conductive layer 11. Heat is then transferred from the two second conducting portions 132 of the adjacent thermally conductive layer 11 to the two second conducting portions 132 of the next thermally conductive layer 11 further away from the solder pad 141. The first and second conducting portions 131, 132 form a tree-like heat conduction path that radiates outward from the circuit board 100, further facilitating heat dissipation and improving the uniformity of heat distribution across the circuit board 100. The horizontal direction refers to the x-direction in the figure.

[0056] It should be emphasized that for second solder pads 1412, the number and placement of openings and second sub-heat-conducting layers 1102 need to be adjusted to ensure that first conductive portion 131 can connect to first solder pad 1411 and second sub-heat-conducting layer 1102 of first heat-conducting layer 111, and that second conductive portion 132 can connect to second sub-heat-conducting layers 1102 of two adjacent second heat-conducting layers 112. As shown in FIG5 , first heat-conducting layer 111 has one second sub-heat-conducting layer 1102, and second heat-conducting layer 112 has two second sub-heat-conducting layers 1102. The distance between the two second sub-heat-conducting layers 1102 gradually increases as it moves away from second solder pad 1412. For first solder pad 1411, because first sub-heat-conducting layer 1101 occupies a relatively large proportion of heat-conducting layer 11, even when the arrangement of conductive portion 13 changes, the connection between first conductive portion 131 and second conductive portion 132 is generally maintained, and no adjustment is required.

[0057] As shown in FIG7 , a third via is provided between the second vias of at least some of the insulating layers 12. The third via is filled with a third conducting portion 133. The third conducting portion 133 is respectively connected to two adjacent thermally conductive layers 11. The third conducting portion 133 is provided between two second conducting portions 132 of the same insulating layer 12. This increases the number of conducting portions 13 between adjacent thermally conductive layers 11, further enhancing the longitudinal thermal conductivity of the circuit board 100. This also reduces the distance between two adjacent conducting portions 13, facilitating heat transfer from one conducting portion 13 to another adjacent conducting portion 13, further enhancing the lateral thermal conductivity of the circuit board 100.

[0058] The number of third conducting portions 133 gradually increases as the distance between two second heat conducting portions increases. It is understood that the greater the distance between two second heat conducting portions, the greater the number of third conducting portions 133 provided between them. While the number of second conducting portions 132 remains constant, the total number of conducting portions 133 increases as the distance away from the solder pad 141 increases. This allows heat to be gradually dispersed both horizontally and vertically within the circuit board 100, further improving heat dissipation uniformity within the circuit board 100.

[0059] In any two adjacent insulating layers 12 along the longitudinal direction, the number of first conducting portions 131 is alternating between an even and odd number. When the number of first conducting portions 131 is an odd number, one of the third conducting portions 133 is longitudinally aligned with the first conducting portion 131. When the number of first conducting portions 131 is an even number, the third conducting portions 133 are symmetrically located on either side of the first conducting portion 131. In the same insulating layer 12, the distance between any two adjacent conducting portions 13 is equal, and the distance between adjacent conducting portions 13 gradually decreases in a direction away from the solder pad 141. This results in a uniform increase in the density of the conducting portions 13 in the longitudinal direction away from the solder pad 141, gradually enhancing the thermal conductivity of the circuit board 100 and dispersing heat without compromising thermal efficiency.

[0060] From top to bottom in the longitudinal direction, there are the first insulating layer 12, the second insulating layer 12, the third insulating layer 12, and the fourth insulating layer 12. The third insulating layer 12 has a third conducting portion 133, and the fourth insulating layer 12 has two third conducting portions 133. The third conducting portion 133 of the third insulating layer 12 and the first conducting portion 131 are located on the same straight line in the longitudinal direction. The third conducting portion 133 of the fourth insulating layer 12 is symmetrically arranged on both sides of the third conducting portion 133 of the third insulating layer 12, and the third conducting portion 133 of the fourth insulating layer 12 is located between the second conducting portion 132 of the second insulating layer 12 and the second conducting portion 132 of the third insulating layer 12, which are adjacent in the transverse direction.

[0061] In a direction away from the solder pad 141, the first insulating layer 12 is provided with one first conducting portion 131, the second insulating layer 12 is provided with two second conducting portions 132, the third insulating layer 12 is provided with three conducting portions 13, and the fourth insulating layer 12 is provided with four conducting portions 13. As the number of conducting portions 13 increases away from the solder pad 141, and the distance between conducting portions 13 gradually decreases, the multiple conducting portions 13 form a grid-like heat transfer path within the circuit board 100. Compared to a tree-like transmission path, this can further improve the uniformity of heat distribution within the circuit board 100.

[0062] In Figure 7 , less heat is directly transferred to the display area of ​​the display panel. Therefore, as shown in Figure 8 , a first hollow portion 111 is provided on the first thermally conductive layer 111 to avoid affecting the thermal conductivity within the circuit board 100. The first thermally conductive layer 111 is typically provided with an even number of third conductive portions 133, with the first hollow portion 111 positioned between the two third conductive portions 133 closest to the first conductive portion 131. The orthographic projection of the solder pad 141 on the first thermally conductive layer 111 is located within the first hollow portion 111. Completely etching away the portion of the first thermally conductive layer 111 located within the first hollow portion 111 can reduce heat transfer to the display area of ​​the display panel, further alleviating the yellowing problem in the display area of ​​the display panel.

[0063] As shown in Figure 9, the cross-sectional areas of the first conductive portion 131, the second conductive portion 132, and the third conductive portion 133 can be configured to gradually increase from their midsection toward their ends. It is understood that the ends of the conductive portion 13 contact the solder pad 141 and the thermally conductive layer 11, where the cross-sectional areas are largest, thereby enhancing the thermal conductivity of the conductive portion 13. The middle portion of the conductive portion 13 contacts the insulating layer 12, which has a lower thermal conductivity than the thermally conductive layer 11. The smaller size of the middle portion of the conductive portion 13 reduces the probability of heat transfer through the insulating layer 12, thereby allowing heat to be conducted away as much as possible through the thermally conductive layer 11, further improving the heat dissipation capacity of the circuit board 100.

[0064] The present disclosure also provides a display device. As shown in Figures 10 to 12, the display device may include a display module and the circuit board 100 mentioned above in the present disclosure. The display module includes a display panel 200, a middle frame, and a heat dissipation mechanism. The circuit board 100 is connected to the display panel 200. The circuit board 100 extends laterally beyond the edge of at least one side of the display panel 200 to form an exposed portion 1113. The exposed portion 1113 is connected to the middle frame or the heat dissipation mechanism. The exposed portion 1113 may also be connected to both the middle frame and the heat dissipation mechanism to further improve the heat dissipation effect of the display device.

[0065] The specific structure and beneficial effects of the circuit board 100 have been described in detail above and will not be further elaborated here. It should be noted that, in addition to the circuit board 100, the display device also includes other necessary components and elements, such as a housing, a power cord, etc. Those skilled in the art may supplement these components based on the specific usage requirements of the display device, and will not be further elaborated here.

[0066] When the circuit board 100 is of the structure shown in the figure, the display device can be a traditional electronic device, such as a mobile phone, a computer, a television, and a camcorder, or it can be an emerging wearable device, such as a virtual reality device and an augmented reality device, which are not listed here one by one.

[0067] As shown in FIG10 , the heat-conducting layer 11 closest to the display panel 200 is the first heat-conducting layer 111. The first heat-conducting layer 111 extends horizontally beyond the edge of one side of the display panel 200, and the exposed portion 1113 is located on the portion of the first heat-conducting layer 111 that extends beyond the display panel 200. Directly overlapping the first heat-conducting layer 111 with the middle frame (not shown in FIG10 ) or the heat dissipation mechanism (not shown in FIG10 ) can further enhance the heat dissipation capacity of the display device. As shown in FIG11 , on this basis, in order to further enhance the performance of the display device, the first heat-conducting layer 111 can be arranged to extend horizontally beyond the edges of both sides of the display panel 200, forming two exposed portions 1113, which are then connected to the middle frame and the heat dissipation mechanism.

[0068] As shown in Figure 12, a second hollow portion 1112 can be provided in the first thermally conductive layer 111. The orthographic projection of the display panel 200 on the first thermally conductive layer 111 is located within the second hollow portion 1112, with exposed portions 1113 located on either side of the second hollow portion 1112. The first thermally conductive layer 111 is completely removed or patterned in the second hollow portion 1112, while the first thermally conductive layer 111 is retained in the exposed portions 1113. This reduces heat transfer to the display panel 200 while facilitating heat transfer to the midframe or heat dissipation mechanism. This significantly reduces hotspot temperatures and heat transfer to the display panel, preventing yellowing of the display area of ​​the display panel 200.

[0069] Those skilled in the art will readily appreciate other embodiments of the present disclosure after considering the specification and practicing the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of the present disclosure that follow the general principles of the present disclosure and include common knowledge or customary techniques in the art not disclosed herein. The description and examples are to be considered as exemplary only, with the true scope and spirit of the present disclosure being indicated by the appended claims.

Claims

1. A circuit board, characterized in that: include: Circuit board body; A binding layer is provided on one side of the circuit board body, the binding layer comprises a pad and a lead, the pad is used to bind electronic components, the lead is connected to the pad, and is used to transmit an electrical signal to the pad or transmit an electrical signal from the pad to the inside of the circuit board; The circuit board body comprises at least two layers of heat-conducting layers, an insulating layer is provided between the soldering pad and the heat-conducting layer, and between two adjacent layers of heat-conducting layers, the insulating layer is provided with a via hole, and the via hole is filled with a conducting part, the conducting part between the soldering pad and the heat-conducting layer is a first conducting part, and the first conducting part is respectively connected to the soldering pad and the heat-conducting layer; the conducting part between two adjacent layers of the heat-conducting layers is a second conducting part, and the second conducting part is respectively connected to two adjacent layers of the heat-conducting layers, and at least two of any two adjacent conducting parts along the longitudinal direction are staggered with each other, and the longitudinal direction is the thickness direction of the circuit board body.

2. The circuit board according to claim 1, characterized in that: The pad includes a first pad, the lead includes a reference signal line, the reference signal line is connected to the first pad and is used to input a reference signal to the first pad, the thermal conductive layer includes a first sub-thermal conductive layer, a first via hole is provided between the first pad and the first sub-thermal conductive layer, the first via hole is filled with a first conducting part, and the first conducting part is respectively connected to the first pad and the first sub-thermal conductive layer.

3. The circuit board according to claim 2, characterized in that: The pad includes a second pad, the lead includes a high-level signal line, the high-level signal line is connected to the second pad, and the high-level signal line is used to input a high-level signal to the second pad, the thermal conductive layer includes a second sub-thermal conductive layer, the second sub-thermal conductive layer and the first sub-thermal conductive layer are insulated from each other, a first via hole is provided between the second pad and the second sub-thermal conductive layer, the first via hole is filled with a first conducting part, and the first conducting part is respectively connected to the second pad and the second sub-thermal conductive layer.

4. The circuit board according to claim 1, characterized in that: At least two first conduction parts are arranged between the solder pad and the heat-conducting layer, and the same number of second conduction parts as the first conduction parts are arranged between every two adjacent heat-conducting layers. The first conduction parts and the second conduction parts closest to the first conduction parts are located on the same straight line along the longitudinal direction, and the longitudinal direction is the thickness direction of the circuit board body.

5. The circuit board according to claim 1, characterized in that: At least one first conduction portion is provided between the solder pad and the heat conducting layer, and two second conduction portions are provided between two adjacent heat conducting layers. The two second conduction portions are located on both sides of the first conduction portion, and the distance between the two second conduction portions gradually increases in the direction away from the solder pad.

6. The circuit board according to claim 4, characterized in that: The heat-conducting layer farthest from the pad is the first heat-conducting layer, a first hollow portion is provided on the first heat-conducting layer, and the orthographic projection of the pad on the first heat-conducting layer is located in the first hollow portion.

7. The circuit board according to claim 6, characterized in that: The remaining heat-conducting layers are second heat-conducting layers, and the second conducting portion between the first heat-conducting layer and the adjacent second heat-conducting layer is arranged on both sides of the first hollow portion.

8. The circuit board according to claim 1, characterized in that: A third via hole is provided between at least some of the second via holes of the insulating layer. The third via hole is filled with a third conduction part which is respectively connected to two adjacent heat conducting layers and is provided between two second conduction parts of the same insulating layer.

9. The circuit board according to claim 8, characterized in that: The number of the third conducting portions gradually increases in a direction away from the pad.

10. The circuit board according to claim 9, characterized in that: In the same insulating layer, the distance between any two adjacent conducting parts is equal, and the distance between adjacent conducting parts gradually decreases in a direction away from the pad.

11. The circuit board according to claim 10, characterized in that: The number of the third conducting parts is alternately arranged in even and odd numbers, the heat conducting layer farthest from the pad is provided with an even number of third conducting parts, and a first hollow part is provided between two third conducting parts closest to the straight line where the first conducting part is located.

12. The circuit board according to claim 1, characterized in that: The cross-sectional areas of the first conducting portion and the second conducting portion gradually increase from the middle portion to both ends thereof.

13. A display device, characterized in that: include: Display module, including display panel, middle frame and heat dissipation mechanism; The circuit board according to any one of claims 1 to 12 is connected to the display panel, the circuit board extends laterally beyond the edge of at least one side of the display panel to form an exposed portion, the exposed portion The exposed portion is connected to the middle frame and / or the heat dissipation mechanism.

14. The display device according to claim 13, characterized in that: The heat-conducting layer closest to the display panel is the first heat-conducting layer, and the exposed portion is located on a portion of the first heat-conducting layer that extends beyond an edge of at least one side of the display panel in a lateral direction.

15. The display device according to claim 14, characterized in that: The first heat-conducting layer is provided with a second hollow portion, the orthographic projection of the display panel on the first heat-conducting layer is located in the second hollow portion, and the exposed portions are located on both sides of the second hollow portion.

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