Large-aperture heat channel heat dissipation device of bottom hot plate device
By designing a large-aperture heat dissipation device on the printed board of the bottom heat disk device, a larger area of heat dissipation channels are formed by cross-shaped extended tropical and large-aperture heat pores, the problem of insufficient heat dissipation performance caused by too small heat dissipation pores in the prior art is solved, and the heat dissipation performance and the reliability of electronic products are significantly improved.
Patent Information
- Application Number
- CN202411741317.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-29
- Publication Date
- 2025-03-14
AI Technical Summary
The heat dissipation pore size of the existing bottom heat disk devices is too small, resulting in insufficient heat dissipation performance of the printed board in high temperature and high humidity environments, which may lead to degradation of electrical performance, increased noise or serious damage.
A large-aperture heat channel heat dissipation device is designed, and a large-aperture heat pore and heat disk are provided on the extended tropical zone to form a larger area of heat dissipation channel to improve heat dissipation performance.
By expanding the size of the heat dissipation via and increasing the heat dissipation path area, the device significantly improves the heat dissipation performance of the Z-axis (vertical direction) heat dissipation channels, ensuring that the heat from the bottom heat disk device can be quickly transmitted to the outside, reducing component temperature, and improving the reliability of electronic products.
Smart Images
Figure CN119629843A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of heat dissipation of circuit boards, and in particular to a large-aperture heat channel heat dissipation device for a bottom heat plate component. Background Art
[0002] At present, the bottom heat plate device has a small package size and fast heat dissipation. It is increasingly used and is increasingly developing towards high functionality and miniaturization. When the printed circuit board is working, the device generates more and more heat and consumes more and more power. In a high temperature and high humidity environment, long-term operation will cause ion migration inside the printed circuit board material, copper layer fracture in the connection hole, and fatigue of the surface welding point. The above reasons will cause the electrical performance to decline, the noise to increase, and even serious damage.
[0003] The bottom heat plate device is a new type of surface mount packaging technology with a small volume. Because the wires between the internal pins are relatively short, the self-inductance coefficient and the resistance of the wiring inside the package are low, so it can provide good electrical performance. Most bottom heat plate devices are equipped with a bottom heat dissipation pad. The heat of the device body needs to be dissipated through the bottom heat plate contacting the printed circuit board to conduct heat, so as to achieve the purpose of reducing the chip temperature. Among the common heat dissipation methods, the most commonly used method is to fix the heat sink on the chip or use a metal heat conductive plate to buckle it on the surface of the chip that needs heat dissipation. The heat is transferred to the chassis through the heat conductive plate. Some scholars have also proposed methods such as thermal grease design and board material design to improve thermal conductivity. The project adopts the printed circuit board end design method, including designing the bottom heat sink and designing array heat dissipation holes on the heat sink. In order to avoid the solder paste from overflowing from the corresponding array heat dissipation holes to the back during welding, the heat dissipation holes are usually designed not to be too large. Another way is to use resin plug hole copper plating technology to plate the array heat dissipation holes flat. However, due to the limitations of resin plug hole copper plating technology, the heat dissipation holes are usually designed not to be too large, and the thermal conductivity of the resin is too low. Therefore, no matter which method is used, the diameter of the heat dissipation vias of the bottom heat sink device cannot be expanded, and the heat dissipation area cannot be expanded, and the effect of effective heat dissipation cannot be achieved.
[0004] In short, in the current design of bottom heat plate devices, the diameter of the array thermal holes at the bottom of the device is too small, which is not conducive to heat dissipation in the negative direction of the Z axis (vertical direction) on the printed circuit board. In addition, the small area of the bottom heat plate also seriously reduces the heat dissipation performance in this direction and reduces the heat transfer rate of the bottom heat plate device. In addition, in the current design method, the solder mask on the back of the printed circuit board device also hinders the heat dissipation performance. Summary of the invention
[0005] The purpose of the present invention is to overcome the deficiencies of the prior art and provide a large-aperture heat channel heat dissipation device for a bottom heat plate device to improve the heat dissipation performance of the bottom heat plate device.
[0006] The objective of the present invention is achieved through the following technical solutions: A large-aperture heat channel heat dissipation device for a bottom heat plate device, comprising a printed circuit board and a bottom heat plate device mounted on the printed circuit board, a bottom heat plate for mounting the bottom heat plate device and signal pads distributed on four sides of the bottom heat plate are provided on the top layer of the printed circuit board, and heat dissipation channels penetrating the entire printed circuit board and distributed in an array are provided on the bottom heat plate; A cross-shaped extended heat belt is arranged in the middle layer of the printed circuit board, and the extended heat belt extends from the central projection position of the bottom heat plate to four directions; A large-aperture thermal hole and a thermal pad are arranged on the extended heat belt in the area not covered by the bottom thermal pad device, wherein the large-aperture thermal hole runs through the entire printed circuit board, and the thermal pad is located around the large-aperture thermal hole; The heat dissipation holes, the cross-shaped extended heat belt and the large-aperture heat hole are connected to form a heat dissipation channel.
[0007] Furthermore, the width of the extended heat belt is less than or equal to half of the total width of a single side of the device signal pad.
[0008] Furthermore, the extended thermal belt is located on the conductor layer of the non-device mounting surface and is arranged in one or more layers in the middle layer of the printed circuit board.
[0009] Furthermore, the diameter D of the large-aperture thermal hole is: Where A is the cross-sectional area perpendicular to the heat flow direction, in mm 2 ; H is the thickness of the printed circuit board, in mm; the calculation formula for the cross-sectional area A perpendicular to the heat flow direction is as follows: in Ф is the heat flow; λ is the thermal conductivity, unit is W / (m·℃); △t is the temperature difference, unit is ℃.
[0010] Furthermore, the signal pads are interconnected through signal holes and microstrip lines, and the signal holes are arranged in non-overlapping areas in a vertical projection direction of the extended tropical zone; the transmission line is a microstrip line, connecting the signal holes and the signal pads.
[0011] Furthermore, the microstrip line width w is calculated by the following formula: Where Z 0 is the single-ended impedance of the microstrip line, ε r is the dielectric constant, h is the distance from the trace to the reference plane, h 1 Line thickness.
[0012] Furthermore, the diameter D of the large-aperture thermal hole ranges from 0.5 mm to 5 mm.
[0013] Furthermore, the diameter of the heat dissipation channels distributed in an array ranges from 0.1 mm to 0.6 mm.
[0014] The beneficial effects of the present invention are: 1) The present invention provides a large-aperture heat channel heat dissipation device for a bottom heat plate device. By arranging an extended heat belt on the conductor layer of the non-device mounting surface of the bottom heat plate device, heat is conducted along the extended heat belt with a larger area, thereby increasing the heat dissipation path area of the printed circuit board of the bottom heat plate device, which is conducive to forming a heat dissipation path with a larger area of thermal radiation.
[0015] 2) The present invention provides a large-aperture heat channel heat dissipation device for a bottom heat plate device. By extending the heat belt and designing a large-aperture heat hole connected to it, the size of the heat dissipation via is enlarged, the heat dissipation performance of the heat dissipation channel in the Z-axis direction (vertical direction) is greatly improved, and it is conducive to forming a heat dissipation path with a larger area of thermal radiation.
[0016] 3) The present invention forms a larger heat dissipation channel, ensuring that the heat at the bottom of the bottom heat plate device can be quickly transferred to the outside, thereby reducing the temperature of the components and the temperature difference, and improving the heat dissipation performance of the bottom heat plate device. It not only reduces the failure of the device caused by the excessive temperature of the bottom heat plate device, but also greatly improves the reliability of electronic products. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] Figure 1 A schematic diagram of the structure of a large-aperture heat channel heat dissipation device of a bottom heat plate device provided by an embodiment of the present invention; Figure 2 A schematic structural diagram of a large-aperture heat channel heat dissipation device of a bottom heat plate device provided by another embodiment of the present invention; Figure 3 A cross-sectional view of a large-aperture heat channel heat sink for a bottom heat plate device; Figure 4 This is a schematic diagram of the heat dissipation channel formed when the extended tropical belt is set as one layer; Figure 5 Schematic diagram of the heat dissipation channel formed when the extended tropical belt is set as two layers. DETAILED DESCRIPTION
[0018] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.
[0019] See also Figure 1-Figure 5 , the present invention provides a technical solution: like Figure 1 , a large-aperture heat channel heat dissipation device for a bottom heat plate device, comprising a printed circuit board and a bottom heat plate device mounted on the printed circuit board, wherein a bottom heat plate for mounting the bottom heat plate device and signal pads distributed on four sides of the bottom heat plate are provided on a top layer of the printed circuit board; The shape of the bottom heat plate of the bottom heat plate device is not limited in the embodiment of the present invention, and only a bottom heat plate device with a square shape is taken as an example; The bottom heat plate is provided with heat dissipation channels which penetrate the entire printed circuit board and are distributed in an array; the diameter range of the heat dissipation channels distributed in an array is 0.1 mm to 0.6 mm.
[0020] A cross-shaped extended heat belt is arranged in the middle layer of the printed circuit board, and the extended heat belt extends from the central projection position of the bottom heat plate to four directions; The width of the extended heat belt is less than or equal to half of the total width of the device signal pad on one side. Figure 1 , the width of the extended heat zone is W, the total width of one side of the device signal pad is W1, and the width of the extended heat zone W is 1 / 2W1.
[0021] A large-aperture thermal hole and a thermal pad are arranged on the extended heat belt in the area not covered by the bottom thermal pad device, wherein the large-aperture thermal hole runs through the entire printed circuit board, and the thermal pad is located around the large-aperture thermal hole; Furthermore, the diameter D of the large-aperture thermal hole is: Where A is the cross-sectional area perpendicular to the heat flow direction, in mm 2 ; H is the thickness of the printed circuit board, in mm; the calculation formula for the cross-sectional area A perpendicular to the heat flow direction is as follows: in Ф is the heat flow; λ is the thermal conductivity, unit is W / (m·℃); △t is the temperature difference, unit is ℃.
[0022] Furthermore, the diameter D of the large-aperture thermal hole ranges from 0.5 mm to 5 mm.
[0023] The cross-sectional view of the large-aperture heat channel heat dissipation device is as follows: Figure 3 As shown, the heat dissipation holes, the cross-shaped extended heat belt and the large-aperture heat hole are connected to form a heat dissipation channel.
[0024] In one embodiment, the printed circuit board may be a double-sided board or a multi-layer board, and the extended heat belt is located on the conductor layer of the non-device mounting surface and is arranged in one or more layers in the middle layer of the printed circuit board.
[0025] When the extended heat belt is set in one of the middle layers of the printed circuit board, the heat dissipation channel formed is as follows Figure 4 shown.
[0026] When the extended heat belt is set in multiple layers in the middle layer of the printed circuit board, the heat dissipation channel formed is as follows Figure 5 shown.
[0027] In one embodiment, the signal pads are interconnected through signal holes and microstrip lines. Figure 2 As shown, the signal hole is arranged in a non-overlapping area in a vertical projection direction of the extended tropical zone; the transmission line is a microstrip line connecting the signal hole and the signal pad.
[0028] The microstrip line width w is calculated by the following formula: Where Z 0 is the single-ended impedance of the microstrip line, ε r is the dielectric constant, h is the distance from the trace to the reference plane, h 1 Line thickness.
[0029] The large-aperture heat channel heat dissipation device provided by the present invention conducts heat from the bottom heat plate through the hole along the larger extension belt, which can expand the heat dissipation path area of the bottom heat plate device printed circuit board. The extension belt is provided with a large-aperture heat hole / plate, which expands the size of the channel heat dissipation pad, is conducive to forming a heat dissipation path for larger area heat radiation, and greatly improves the heat dissipation performance of the heat dissipation channel in the negative direction (vertical direction) of the Z axis. The present invention forms a larger area heat dissipation channel, which ensures that the heat at the bottom of the bottom heat plate device can be quickly conducted to the outside, so as to achieve the purpose of reducing the component temperature and reducing the temperature difference. It not only reduces the device failure caused by the excessive temperature of the bottom heat plate device, but also greatly improves the reliability of electronic products.
[0030] The above is only a preferred embodiment of the present invention. It should be understood that the present invention is not limited to the form disclosed herein, and should not be regarded as excluding other embodiments, but can be used in various other combinations, modifications and environments, and can be modified within the scope of the concept described herein through the above teachings or the technology or knowledge of the relevant field. The changes and modifications made by those skilled in the art shall not deviate from the spirit and scope of the present invention, and shall be within the scope of protection of the claims attached to the present invention.
Claims
1. A large-aperture heat channel heat dissipation device for a bottom heat plate device, comprising a printed circuit board and a bottom heat plate device mounted on the printed circuit board, wherein the top layer of the printed circuit board has a bottom heat plate for mounting the bottom heat plate device and signal pads distributed on four sides of the bottom heat plate, characterized in that: The bottom heat plate is provided with heat dissipation channels that penetrate the entire printed circuit board and are distributed in an array; A cross-shaped extended heat belt is arranged in the middle layer of the printed circuit board, and the extended heat belt extends from the central projection position of the bottom heat plate to four directions; A large-aperture thermal hole and a thermal pad are arranged on the extended heat belt in the area not covered by the bottom thermal pad device, wherein the large-aperture thermal hole runs through the entire printed circuit board, and the thermal pad is located around the large-aperture thermal hole; The heat dissipation holes, the cross-shaped extended heat belt and the large-aperture heat hole are connected to form a heat dissipation channel.
2. A large-aperture heat channel heat dissipation device for a bottom heat plate device according to claim 1, characterized in that: The width of the extended heat belt is less than or equal to half of the total width of a single side of the device signal pad.
3. A large-aperture heat channel heat dissipation device for a bottom heat plate device according to claim 1, characterized in that: The extended heat belt is located on the conductor layer of the non-device mounting surface and is arranged in one or more layers in the middle layer of the printed circuit board.
4. A large-aperture heat channel heat dissipation device for a bottom heat plate device according to claim 1, characterized in that: The diameter D of the large-diameter thermal hole is: Where A is the cross-sectional area perpendicular to the heat flow direction, in mm 2 ; H is the thickness of the printed circuit board, in mm; the calculation formula for the cross-sectional area A perpendicular to the heat flow direction is as follows: in Ф is the heat flow; λ is the thermal conductivity, unit is W / (m·℃); △t is the temperature difference, unit is ℃.
5. The large-aperture heat channel heat dissipation device of a bottom heat plate device according to claim 1, characterized in that: The signal pads are interconnected via signal holes and microstrip lines, wherein the signal holes are arranged in non-overlapping areas in a vertical projection direction of the extended heat belt; the transmission line is a microstrip line, connecting the signal holes and the signal pads.
6. A large-aperture heat channel heat dissipation device for a bottom heat plate device according to claim 5, characterized in that: The microstrip line width w is calculated by the following formula: Where Z0 is the single-ended impedance of the microstrip line, ε r is the dielectric constant, h is the distance from the trace to the reference plane, h 1 Line thickness.
7. A large-aperture heat channel heat dissipation device for a bottom heat plate device according to claim 4, characterized in that: The diameter D of the large-aperture thermal hole ranges from 0.5 mm to 5 mm.
8. The large-aperture heat channel heat dissipation device of a bottom heat plate device according to claim 1, characterized in that: The diameter of the heat dissipation holes distributed in an array ranges from 0.1 mm to 0.6 mm.