Chip heat dissipation structure facing large-scale impact

Abstract

The invention provides a chip heat dissipation structure facing large-scale impact. The chip heat dissipation structure comprises a main heat dissipation plate, an auxiliary heat dissipation plate, heat conduction silicone grease, a heat conduction pad and an adjusting gasket. The chip is installed on the circuit board, the heat conduction pad is pasted or placed on the top, and heat conduction silicone grease is smeared on the side wall. The main radiating plate is mounted on the circuit board, a through hole for accommodating a chip is formed in the main radiating plate, a heat source end of the main radiating plate is in contact with the heat-conducting silicone grease, and a radiating end is in contact with a cold source to radiate heat of the chip; the auxiliary heat dissipation plate is arranged on the heat conduction pad, and after the heat conduction pad is compressed to a set compression ratio, the auxiliary heat dissipation plate is fixedly connected with the main heat dissipation plate. The compression amount of the heat conduction pad of the heat dissipation structure can be adjusted, it can be guaranteed that the compression amount of the heat conduction pad of each set of product is consistent, and the heat dissipation efficiency is improved; after the heat dissipation structure of the product is installed, the chip is not subjected to additional installation stress, and the strong impact resistance of the heat dissipation structure is improved.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of chip heat dissipation, and particularly relates to a chip heat dissipation structure capable of resisting large-scale impact. BACKGROUND

[0002] At present, with the continuous improvement of the operation speed of a chip, the heat power of the chip is getting stronger and stronger. Therefore, the heat dissipation design of the electronic chip is essential in the structural design. In the field of aviation and aerospace, the mechanical environment of products is relatively harsh, and there are complex external environments such as low air pressure and weightlessness. Therefore, heat conduction is still the main form of chip heat dissipation. The chip and the heat dissipation structure are usually rigidly connected, and strong impact will cause the chip to be subjected to local instantaneous stress and the connection between the chip and the heat dissipation structure to fail. Therefore, resisting large-scale impact has become the main direction of heat dissipation design in this field.

[0003] The requirement of resisting impact is that the chip and the heat dissipation structure must be flexibly connected, and more importantly, the heat dissipation structure cannot generate residual stress on the chip after installation. At present, the heat dissipation structure is not adjustable after installation. Due to the tolerances of the height of the chip itself, the height of the solder joint, and the machining of the heat dissipation structure, the compression amount of the heat conduction pad after the installation of the chip on the heat dissipation structure is not enough, which leads to the decrease of the heat conduction performance, or the compression amount is too large, which causes the chip to be subjected to a large installation stress, and there are many hidden dangers. SUMMARY

[0004] In order to overcome the deficiencies in the prior art, the present application provides a chip heat dissipation structure capable of resisting large-scale impact. The compression amount of the heat conduction pad of the heat dissipation structure is adjustable and can ensure that the compression amount of the heat conduction pad of each product is consistent, thereby improving the heat dissipation efficiency. The chip will not be subjected to additional installation stress after the installation of the product on the heat dissipation structure, thereby improving the anti-impact capability of the heat dissipation structure.

[0005] The technical scheme provided by the present application is as follows:

[0006] In a first aspect, a chip heat dissipation structure includes a main heat dissipation plate, a secondary heat dissipation plate, a heat conduction silicone grease, a heat conduction pad, and an adjustment washer.

[0007] The chip is installed on a circuit board, the top of the chip is pasted or placed with the heat conduction pad, and the sidewall of the chip is coated with the heat conduction silicone grease.

[0008] The main heat dissipation plate is installed on the circuit board, a through hole for accommodating the chip is formed in the main heat dissipation plate, the heat source end of the main heat dissipation plate contacts the heat conduction silicone grease, and the heat dissipation end of the main heat dissipation plate contacts a cold source, so as to implement the heat dissipation of the chip.

[0009] The secondary heat dissipation plate is arranged on the heat conduction pad, the heat conduction pad is compressed to a set compression ratio, and the secondary heat dissipation plate is tightly connected with the main heat dissipation plate through the adjustment washer between the secondary heat dissipation plate and the main heat dissipation plate.

[0010] The second aspect is a mounting method of a chip heat dissipation structure, comprising the following steps:

[0011] Pasting or placing a heat-conducting pad on the chip;

[0012] Spreading heat-conducting silicone grease on the four sidewalls of the chip;

[0013] Fastening the main heat dissipation plate with the circuit board, and cleaning the squeezed heat-conducting silicone grease after fastening;

[0014] Placing the auxiliary heat dissipation plate on the heat-conducting pad, compressing the heat-conducting pad by placing a weight on the auxiliary heat dissipation plate, and measuring the distance between the compressed auxiliary heat dissipation plate and the main heat dissipation plate;

[0015] Placing an adjusting gasket with a thickness equal to the distance in the gap between the main heat dissipation plate and the auxiliary heat dissipation plate;

[0016] Finally, fixing the auxiliary heat dissipation plate and the adjusting gasket on the main heat dissipation plate from the top or the side by using fastening screws.

[0017] The chip heat dissipation structure provided by the present application has the following beneficial effects:

[0018] (1) The chip heat dissipation structure provided by the present application conducts heat from the chip shell to the cold source through heat conduction, adjusts the thickness of the adjusting gasket through the installation mode of the auxiliary heat dissipation plate, ensures the actual compression ratio of the heat-conducting pad by adjusting the thickness of the adjusting gasket, and avoids the following problems caused by the large height tolerance after chip welding: (a) the height after chip welding is too low, the heat-conducting pad cannot contact the chip, and heat dissipation is not achieved; (b) the height after chip welding is too high, the compression amount of the heat-conducting pad is too large, causing excessive installation prestress of the chip and thus failing to pass the large-level impact mechanical test;

[0019] (2) The chip heat dissipation structure provided by the present application contacts the upper surface of the chip through the adjusting gasket and the heat-conducting pad as the main heat dissipation surface, spreads heat-conducting silicone grease around the chip as the secondary heat dissipation surface, and contacts the main heat dissipation surface and the secondary heat dissipation surface with the main heat dissipation plate as the main heat conduction path to conduct heat to the cold source;

[0020] (3) The chip heat dissipation structure provided by the present application has no heat insulation pad between the heat source end of the main heat dissipation plate and the circuit board, and has a heat insulation pad between the heat dissipation end of the main heat dissipation plate and the circuit board; the heat insulation pad forms an insulating wall between the main heat dissipation plate and the circuit board, avoiding the secondary heating of the components at the far end (heat dissipation end) of the circuit board by the heat conducted to the main heat dissipation plate;

[0021] (4) The present invention provides a chip heat dissipation structure that can withstand large-scale impacts. After the main heat sink and the circuit board are fastened, and the auxiliary heat sink is installed, the main heat sink, the circuit board and the auxiliary heat sink form a cavity that closes the chip, which can prevent the thermal grease from flowing and failing under large-scale impacts. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic cross-sectional structural diagram of the present invention.

[0023] Figure 1 In the figure, 1 is the main heat sink, 2 is the circuit board, 3 is the auxiliary heat sink, 4 is the chip, 5 is the fastening screw III, 6 is the fastening screw I, 7 is the cold source, 8 is the adjustment gasket, 9 is the thermal grease, 10 is the thermal pad, 11 is the fastening screw II, 12 is the gasket II, 13 is the gasket I, and 14 is the insulation pad.

[0024] Figure 2 This is a schematic diagram of the structural pre-installation of the present invention.

[0025] Figure 3 It is a schematic diagram of structural debugging of the present invention. Figure 3 In the figure, 15 is the standard plug gauge and 16 is the weight.

[0026] Figure 4 This is a schematic diagram of the final installation of the structure of the present invention. DETAILED DESCRIPTION

[0027] The following detailed description of the present invention will make the features and advantages of the present invention more clear and explicit.

[0028] The word “exemplary” is used exclusively herein to mean “serving as an example, example, or illustration.” Any embodiment described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other embodiments.

[0029] like Figure 1 As shown, the present invention provides a chip heat dissipation structure that can withstand a large number of impacts, designs a heat conduction structure with an adjustable compression amount of the thermal pad 10, designs a closed cavity to limit the thermal grease 9, and designs an insulating pad 14 to prevent the main heat dissipation plate 1 from heating the circuit board 2 secondary.

[0030] The heat dissipation structure includes: a main heat dissipation plate 1, an auxiliary heat dissipation plate 3, a thermal pad 10, thermal grease 9, an adjustment gasket 8, a fastening screw I 6, a fastening screw II 11, a fastening screw III 5, a gasket I 13, a gasket II 12 and an insulation pad 14.

[0031] Chip 4 is installed on the circuit board 2, the chip 4 top paste or place the heat-conducting pad 10, the chip 4 side wall is smeared with heat-conducting silicone grease 9.Heat-conducting pad 10 is recommended as single layer, and the interface thermal resistance of multi-layer heat-conducting pad 10 will reduce the performance of high-performance heat-conducting pad.

[0032] The main heat sink 1 is provided with a through hole for accommodating the chip 4, the heat source end of the main heat sink 1 is fastened with the circuit board 2 by using the fastening screw II 11 and the gasket II 12, the heat dissipation end is fastened with the circuit board 2 by using the fastening screw I 6 and the gasket I 13, there is no heat insulation pad between the heat source end of the main heat sink 1 and the circuit board 2, and the heat insulation pad 14 is arranged between the heat dissipation end of the main heat sink 1 and the circuit board 2; the heat insulation pad 14 forms a heat insulation wall surface between the main heat sink 1 and the circuit board 2, so that the heat conducted to the main heat sink 1 is prevented from secondarily heating the components on the far end (heat dissipation end) of the circuit board 2.The heat source end of the main heat sink 1 contacts the heat-conducting silicone grease 9, and the heat dissipation end contacts the cold source 7, so that the chip is cooled; the cold source can be a base body carrying the circuit board and the heat dissipation structure, or other structures installed on the base body as the cold source.

[0033] The auxiliary heat sink 3 is arranged on the heat-conducting pad 10, and after the heat-conducting pad 10 is compressed to a set compression ratio, the auxiliary heat sink 3 is fastened and connected with the main heat sink 1 by adjusting the gasket 8.

[0034] (a) top fixation: the auxiliary heat sink 3 covers the upper surface of the heat-conducting pad (10), the adjusting gasket 8 is arranged between the auxiliary heat sink 3 and the main heat sink 1, and the fastening screw III 5 is sequentially threaded through the auxiliary heat sink 3, the adjusting gasket 8 and the main heat sink 1 to complete the fastening and connection;

[0035] The adjusting gasket 8 is designed of copper material with strong heat-conducting performance, so that the heat received by the auxiliary heat sink 3 can be quickly transmitted to the cold source 7 through the copper gasket and the main heat sink 1.

[0036] (b) side fixation: the outer wall of the through hole structure of the main heat sink 1 for accommodating the chip is processed with a waist hole, and the fastening screw III 5 is sequentially threaded through the waist hole of the main heat sink 1 and the auxiliary heat sink 3 from the side to complete the fastening connection of the two.

[0037] After the main heat sink 1 and the circuit board 2 are fastened by the fastening screw II 11 and the gasket II 12, and the auxiliary heat sink 3 is installed, the main heat sink 1, the circuit board 2 and the auxiliary heat sink 3 form a closed cavity for accommodating the chip and the heat-conducting silicone grease 9, so that the heat-conducting silicone grease can be prevented from flowing and failing under a large amount of impact.

[0038] All fastening screws must be provided with a fastening torque when fastened, so as to not only ensure that the circuit board 2 is not damaged after fastening, but also ensure the consistency of each set of products.

[0039] The application also provides a mounting method of the chip heat dissipation structure against a large amount of impact, such as Figures 2 to 4As shown, comprising the following steps:

[0040] The heat-conducting pad 10 is pasted or placed on the chip 4;

[0041] The heat-conducting silicone grease 9 is applied on the four side walls of the chip 4;

[0042] The main heat sink 1 and the circuit board 2 are fastened by the fastening screw I 6, the fastening screw II 11, the gasket I 13, the gasket II 12 and the heat-insulating pad; after fastening, the extruded heat-conducting silicone grease 9 is cleaned;

[0043] The auxiliary heat sink 3 is placed on the heat-conducting pad 10, and the heat-conducting pad 10 is compressed by placing the weight 16 on the auxiliary heat sink 3; the distance between the compressed auxiliary heat sink 3 and the main heat sink 1 is measured by the plug gauge 15;

[0044] The adjusting gasket 8 with the same thickness as the distance is placed in the gap between the main heat sink 1 and the auxiliary heat sink 3;

[0045] Finally, the auxiliary heat sink 3 and the adjusting gasket 8 are fixed on the main heat sink 1 by the fastening screw III 5 from the top or the side.

[0046] After the auxiliary heat sink 3 contacts the heat-conducting pad 10, the heat-conducting pad 10 is compressed by placing the weight 16 on the auxiliary heat sink 3; the auxiliary heat sink 3 is provided with a slot in the middle of the top to ensure that the compression position of the weight of each product is in the center.

[0047] The weight of the weight 16 is determined by the area and thickness of the heat-conducting pad 10 and the set compression ratio; first, the height h1 of the auxiliary heat sink 3 without the weight is recorded, then the height h2 of the auxiliary heat sink 3 under different weights is recorded, and (h1-h2) / h1 is the compression ratio of the heat-conducting pad 10. The ideal compression ratio is the compression ratio at which the heat-conducting effect is the best and the pressure on the chip 4 is the least; the set compression ratio is close to or equal to the ideal compression ratio as much as possible to avoid chip failure under a large amount of impact.

[0048] The present application is described in detail in combination with the specific embodiments and exemplary examples, but these descriptions cannot be understood as limitations of the present application. Those skilled in the art understand that the technical solutions and embodiments of the present application can be variously replaced, modified or improved without departing from the spirit and scope of the present application, and these all fall within the scope of the present application. The protection scope of the present application is subject to the appended claims.

[0049] The contents not described in detail in the specification of the present application are the known technology of those skilled in the art.

Claims

1. A chip heat dissipation structure, characterized in that: It comprises a main heat sink (1), an auxiliary heat sink (3), thermal grease (9), a thermal pad (10) and an adjustment gasket (8); The chip (4) is mounted on the circuit board (2), a thermal pad (10) is attached or placed on the top, and thermal grease (9) is applied to the side walls; The main heat sink (1) is mounted on the circuit board (2). A through hole for accommodating the chip (4) is provided on the main heat sink (1). The heat source end of the main heat sink contacts the thermal grease (9), and the heat dissipation end contacts the cold source (7) to implement chip heat dissipation. The auxiliary heat sink (3) is arranged on the heat conducting pad (10), and after the heat conducting pad (10) is compressed to a set compression ratio, it is fastened to the main heat sink (1) via an adjustment gasket (8) between the auxiliary heat sink (3) and the main heat sink (1).

2. The chip heat dissipation structure according to claim 1, characterized in that: The heat source end and the heat dissipation end of the main heat dissipation plate (1) are fastened to the circuit board (2) using fastening screws and gaskets; no heat insulation pad is provided between the heat source end and the circuit board (2); and a heat insulation pad (14) is provided between the heat dissipation end and the circuit board (2).

3. The chip heat dissipation structure according to claim 1, characterized in that: The auxiliary heat sink (3) covers the upper surface of the thermal pad (10); the adjustment gasket (8) is made of a thermally conductive material; the auxiliary heat sink (3) and the main heat sink (1) are fastened together by fastening screws that pass through the auxiliary heat sink (3), the adjustment gasket (8) and the main heat sink (1) in sequence.

4. The chip heat dissipation structure according to claim 1, characterized in that: A waist hole is machined on the outer wall of the through-hole structure of the main heat sink (1) for accommodating the chip, and the auxiliary heat sink (3) and the main heat sink (1) are fastened together by fastening screws that pass through the waist hole of the main heat sink (1) and the auxiliary heat sink (3) in sequence from the side.

5. The chip heat dissipation structure according to claim 1, characterized in that: A slot is provided in the middle of the top of the auxiliary heat sink (3) for placing a heavy object for compressing the heat conductive pad at a fixed point.

6. The chip heat dissipation structure according to claim 1, characterized in that: The main heat sink (1), the circuit board (2), the auxiliary heat sink (3) and the adjustment gasket (8) form a cavity that encloses the chip and the thermal grease.

7. The chip heat dissipation structure according to claim 1, characterized in that: The thermal conductive pad (10) is a single-layer thermal conductive pad.

8. The chip heat dissipation structure according to claim 1, characterized in that: The cooling source is a substrate that carries the circuit board and the heat dissipation structure, or a structure installed on the substrate that serves as a cooling source.

9. A method for installing the chip heat dissipation structure according to any one of claims 1 to 8, characterized in that: The steps include: Glue or place the thermal pad on the chip; Apply thermal grease to the side walls of the chip; Fasten the main heat sink to the circuit board and clean the squeezed thermal grease after fastening; Place the auxiliary heat sink on the thermal pad, place a heavy object on the auxiliary heat sink to compress the thermal pad, and measure the distance between the compressed auxiliary heat sink and the main heat sink. Place an adjustment gasket with the same thickness as this distance into the gap between the main heat sink and the auxiliary heat sink; Finally, use fastening screws to fix the auxiliary heat sink and adjustment gasket to the main heat sink from the top or side.

10. The method for installing a chip heat dissipation structure according to claim 9, wherein: The weight used to compress the thermal pad is a weight.

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