CN213847398U - Circuit board heat radiation structure and electrical equipment - Google Patents
Circuit board heat radiation structure and electrical equipment Download PDFInfo
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- CN213847398U CN213847398U CN202022890647.XU CN202022890647U CN213847398U CN 213847398 U CN213847398 U CN 213847398U CN 202022890647 U CN202022890647 U CN 202022890647U CN 213847398 U CN213847398 U CN 213847398U
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Abstract
The utility model relates to a circuit board heat dissipation technical field discloses a circuit board heat radiation structure and electrical equipment. This circuit board heat radiation structure includes: the circuit board assembly comprises a circuit board and a patch power device attached to a first surface of the circuit board, wherein a second surface of the circuit board, which is opposite to the first surface, is provided with a heat-conducting metal layer, and a heat-conducting path is arranged between the heat-conducting metal layer and the patch power device; a thermally conductive insulating medium connected to the second surface of the circuit board; and the radiator is connected to one side of the heat-conducting insulating medium, which is far away from the circuit board assembly, and is used for radiating the circuit board assembly. The utility model provides a circuit board heat radiation structure is through setting up heat conduction route and heat conduction metal level on the circuit board, and the rethread sets up heat conduction insulating medium and the radiator that the heat conduction is connected, can give off the heat fast transfer that the circuit board subassembly during operation produced for the radiator, and this radiating efficiency who has improved paster power device.
Description
Technical Field
The utility model discloses embodiment relates to circuit board heat dissipation technical field, especially relates to a circuit board heat radiation structure and electrical equipment who has this kind of circuit board heat radiation structure.
Background
Power supply products are widely used in electrical equipment. These power supply products are generally composed of a housing and a circuit board and related devices mounted in the housing. The circuit board is provided with a relevant circuit, and the circuit is composed of a large number of electronic components. Due to the restriction of the application environment of the power supply product, the size of the shell of the power supply product is usually small, and the power supply product can generate more heat inside the power supply product when working.
In some power supply product applications, a Metal Oxide Semiconductor (MOS) transistor can be attached to a tin surface of a circuit board, and then a heat-conducting insulating gasket is directly adopted to contact the casing, that is, the heat of the MOS transistor is transferred to the casing through the heat-conducting insulating gasket for heat dissipation.
For example, fig. 1 is a schematic structural diagram of a related art power supply product. The power supply product comprises a machine shell 1, wherein a circuit board 2 is arranged in the machine shell 1, heat-conducting silica gel 4 is arranged between the circuit board 2 and the inner bottom wall of the machine shell 1, and a power device on the circuit board 2 adopts a patch power tube 3. In order to ensure that the patch power tube 3 is pressed on the circuit board 2, the top surface of the patch power tube 3 is provided with a steel pressing sheet 5, and the steel pressing sheet 5 is also beneficial to heat dissipation of the patch power tube 3 when pressing the patch power tube 3.
However, in the above power supply product, since the tin surface of the circuit board 2 has a certain height, the insulating pad, such as the heat conductive silicone, is relatively thick, the thermal resistance thereof is increased, and the heat dissipation efficiency of the high-power and high-loss patch MOS transistor is lowered. In addition, the thin casing design adopted by the current power supply product has poor casing heat dissipation effect, small bottom air cooling surface area and poor heat dissipation capability, and is difficult to meet the design requirement. Moreover, the design needs to have enough pressure to ensure that the patch MOS tube or other indirect heat transfer components are fully contacted with the heat conduction insulating gasket, the requirement on the locking screw of the single plate is higher, and the limited design space of the circuit board is occupied, so that the difficulty in earlier stage design of the circuit board is increased.
Accordingly, there is a need for improvements that overcome the above-mentioned deficiencies.
SUMMERY OF THE UTILITY MODEL
The utility model discloses the main technical problem who solves of embodiment provides a can improve paster power device radiating efficiency's circuit board heat radiation structure.
In order to solve the above technical problem, the utility model discloses a technical scheme that embodiment adopted is: in one aspect, a circuit board heat dissipation structure is provided, including: the circuit board assembly comprises a circuit board and a patch power device attached to a first surface of the circuit board, wherein a second surface of the circuit board, which is opposite to the first surface, is provided with a heat-conducting metal layer, and a heat-conducting path is arranged between the heat-conducting metal layer and the patch power device; a thermally conductive insulating medium connected to the second surface of the circuit board; the radiator is connected to one side, far away from the circuit board assembly, of the heat-conducting insulating medium and used for radiating the circuit board assembly.
In some embodiments, the heat sink has a positioning column, and the positioning column is inserted into the heat conducting insulating medium and the circuit board to position the heat conducting insulating medium and the circuit board.
In some embodiments, the length of the positioning post is greater than the thickness of the heat conducting insulating medium and less than the total thickness of the heat conducting insulating medium and the circuit board.
In some embodiments, the circuit board is provided with an electroless through hole for the positioning column to be inserted and matched.
In some embodiments, the heat conducting and insulating medium is a ceramic substrate, and adhesive layers are disposed between the heat sink and the ceramic substrate and between the ceramic substrate and the circuit board.
In some embodiments, the thermally conductive insulating medium is a viscous thermally conductive insulating film.
In some embodiments, a heat dissipation pad is arranged on the first surface of the circuit board, and the heat dissipation pad is welded with a pad of the patch power device; the circuit board is provided with a via hole, the via hole penetrates through the heat dissipation pad and the heat conduction metal layer, and a via hole metal layer is arranged in the via hole and serves as the heat conduction path; the via hole metal layer is in contact connection with the heat dissipation pad and the heat conduction metal layer.
In some embodiments, the via and the via metal layer are plated through holes.
In some embodiments, the power devices on the circuit board include only patch power devices.
In some embodiments, a driving circuit of the patch power device is further disposed on the circuit board.
In order to solve the above technical problem, the utility model discloses a technical scheme that embodiment adopted is: in another aspect, an electrical device is provided, which includes a housing and a circuit board heat dissipation structure according to any one of the above mentioned embodiments, wherein the circuit board heat dissipation structure is located in the housing.
Compared with the prior art, the embodiment of the utility model provides a circuit board heat radiation structure is through setting up heat conduction route and heat conduction metal level on the circuit board, and the rethread sets up heat conduction insulating medium and the radiator that the heat conduction is connected, can with the heat fast transfer that the circuit board components during operation produced gives the radiator gives off, and this radiating efficiency who has improved paster power device.
Drawings
One or more embodiments are illustrated by way of example in the accompanying drawings, which correspond to the figures in which like reference numerals refer to similar elements and which are not to scale unless otherwise specified.
Fig. 1 is a schematic structural view of a related art power supply product;
fig. 2 is a schematic front view of a circuit board heat dissipation structure according to an embodiment of the present invention;
fig. 3 is a schematic side view of a heat dissipation structure of a circuit board according to an embodiment of the present invention.
The reference numbers illustrate: 100-circuit board heat dissipation structure, 10-circuit board assembly, 11-circuit board, 12-patch power device, 13-non-electroplating through hole, 20-heat conduction insulating medium, 21-through hole, 30-radiator and 31-positioning column.
Detailed Description
In order to facilitate understanding of the present invention, the present invention will be described in more detail with reference to the accompanying drawings and specific embodiments. It is noted that when an element is referred to as being "secured to"/"mounted to" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may be present. The terms "upper", "lower", "outer", "vertical", "horizontal", and the like used in this specification indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience of describing the present invention and simplifying the description, but do not indicate or imply that the device or element referred to must have a particular orientation, be constructed in a particular orientation, and be operated, and thus should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.
Furthermore, the technical features mentioned in the different embodiments of the invention described below can be combined with each other as long as they do not conflict with each other.
Referring to fig. 2 and 3, an embodiment of the invention provides a circuit board heat dissipation structure 100, which mainly includes a circuit board assembly 10, a heat conductive insulating medium 20 and a heat sink 30. The heat conducting insulating medium 20 is sandwiched between the circuit board assembly 10 and the heat sink 30, and is used for transferring heat generated during operation of the circuit board assembly 10 to the heat sink 30 for emission.
Specifically, the circuit board assembly 10 may include a circuit board 11 and a patch power device 12 mounted on a first surface of the circuit board 11, a second surface of the circuit board 11 opposite to the first surface has a heat-conducting metal layer, and a heat-conducting path is formed between the heat-conducting metal layer and the patch power device 12; the heat conductive insulating medium 20 is connected to the second surface of the circuit board 11; the heat sink 30 is connected to a side of the heat-conducting insulating medium 20 away from the circuit board assembly 10, and is used for dissipating heat from the circuit board assembly 10.
The circuit board 11 may be a Printed Circuit Board (PCB). The patch power device 12 may be a patch power transistor, such as a patch MOS transistor. The circuit board 11 may be a multi-layer board structure, such as a two-layer circuit board; wherein, the first surface of the circuit board 11 may have a copper foil layer as a surface of a patch element; the second surface of the circuit board 11 has a heat conducting metal layer, such as the same copper foil layer, used as a copper foil heat dissipation surface; it is noted that the above-mentioned heat-conducting metal layer can be obtained by eliminating the conventional solder resist ink applied to the second surface when the circuit board is manufactured, so that the metal layer such as copper foil is exposed.
The number of the chip power devices 12 may be one or more, and the chip power devices may be soldered on the first surface of the circuit board 11 by a chip mounter. A heat conduction path is formed between the heat conduction metal layer on the second surface of the circuit board 11 and the patch power device 12, and is used for conducting heat generated by the patch power device 12 during operation to the heat conduction metal layer, and further transferring the heat to the heat sink 30. In the illustrated embodiment eight patch power devices 12.
Therefore, in the above embodiment, by providing the heat conducting path and the heat conducting metal layer on the circuit board 11 and then by providing the heat conducting insulating medium 20 and the heat sink 30 which are connected in a heat conducting manner, the heat generated during the operation of the circuit board assembly 10 can be quickly transferred to the heat sink 30 for dissipation, which improves the heat dissipation efficiency of the patch power device.
In some further embodiments, the heat sink 30 may have a positioning column 31, and the positioning column 31 may be sequentially inserted into the heat conducting and insulating medium 20 and the circuit board 11 for positioning the heat conducting and insulating medium 20 and the circuit board 11. The number of the positioning posts 31 may be one, two or more, and in the illustrated embodiment, two positioning posts 31. The cross section of the positioning column 31 can be circular, oval, square, rectangular and the like; in the illustrated embodiment, circular. By providing the positioning posts 31, the heat conducting and insulating medium 20 and the circuit board assembly 10 can be conveniently mounted and positioned on the heat sink 30. Accordingly, positioning holes may be provided in the heat conductive insulating medium 20 and the circuit board 11 so as to insert the positioning posts 31. It is easily understood that when the heat conductive and insulating medium 20 is formed of a heat conductive and insulating adhesive, it is not necessary to provide positioning holes in advance for the heat conductive and insulating medium 20.
In further embodiments, the length of the positioning column 31 is greater than the thickness of the heat conducting and insulating medium 20, and may be less than the total thickness of the heat conducting and insulating medium 20 and the circuit board 11. By such a design, the positioning column 31 can be inserted into the circuit board 11 through the heat conducting and insulating medium 20 and does not protrude from the first surface of the circuit board 11, so that the chip mounting of the chip power device 12 is not hindered.
In further embodiments, the circuit board 11 is provided with an electroless plated through hole 13 for the positioning post 31 to be inserted and fitted. Since circuit board design and fabrication typically involves Non-plated Through holes (NPTH), these Non-plated Through holes 13 can be pre-positioned and sized without additional drilling after the circuit board is fabricated. For example, the number of the non-plated through holes 13 may be the same as the number of the positioning posts 31, and the diameter of the through holes may be slightly larger than the diameter of the positioning posts 31, for example, about 0.2mm larger, so as to facilitate assembly.
In some further embodiments, the heat conducting and insulating medium 20 may be a ceramic substrate, and an adhesive layer is disposed between the heat sink 30 and the ceramic substrate and between the ceramic substrate and the circuit board 11. Since the ceramic substrates do not have adhesiveness, when assembling such a heat conductive and insulating medium 20, an adhesive agent is required to bond between the heat sink 30 and the ceramic substrates and between the ceramic substrates and the circuit board 11; accordingly, these adhesives form the above-mentioned adhesive layer after curing. When the bonding layer is thin, the bonding layer does not generate great resistance to heat conduction; in addition, a thermally conductive adhesive is also used to further enhance the heat transfer.
Further, when a ceramic substrate is used as the heat conducting and insulating medium 20, the ceramic substrate may be provided with a through hole 21 for mounting and positioning. The number of the through holes 21 may be the same as the number of the positioning pillars 31, and the diameter of the through holes 21 may be slightly larger than the diameter of the positioning pillars 31, for example, about 0.2mm larger, so as to facilitate assembly.
In other embodiments, the thermally conductive and insulating medium 20 may also be a viscous thermally conductive insulating film. Such a viscous heat-conductive insulating film may be different from the adhesive agent for forming the adhesive layer described above; but rather a pre-fabricated plate that may be attached to the second surface of the circuit board 11 or to the heat sink 30 prior to mating with the heat sink 30 or the circuit board 11, respectively, during assembly. For example, the thermally conductive and insulating medium 20 in this embodiment may be a thermally conductive and insulating film like a double-sided tape.
In further some embodiments, a heat dissipation pad is disposed on the first surface of the circuit board 11, and the heat dissipation pad is soldered to a pad of the chip power device 12; the circuit board 11 is provided with a via hole, the via hole penetrates through the heat dissipation pad and the heat conduction metal layer, and a via hole metal layer is arranged in the via hole to serve as the heat conduction path; the via hole metal layer is in contact connection with the heat dissipation pad and the heat conduction metal layer. The heat-dissipating pads may be included in a copper foil on the first surface of the circuit board 11. The via hole may be formed during a manufacturing process of a circuit board, and the via hole metal layer is inserted into the via hole and is in contact connection with the heat dissipation pad and the heat conductive metal layer to conduct heat from the heat dissipation pad to the heat conductive metal layer.
For example, the via may pass through the thermal pad; wherein the diameter of the via hole may be 0.2 to 0.4mm, and the diameter of the heat dissipation pad may be greater than the diameter of the via hole, for example, 0.4 to 0.7 mm. For another example, the via and the via metal layer may be Plated Through Holes (PTHs). Since circuit board design and fabrication typically involves plated through holes, these plated through holes can be pre-positioned and sized without the need for additional positioning after the circuit board is fabricated.
In further embodiments, the power devices on the circuit board 11 may include only the patch power devices 12. In addition, a driving circuit for the patch power device 12 is further disposed on the circuit board 11. In the conventional circuit substrate design, the design requirements may not be satisfied due to space limitations or circuit board layout limitations, but in the embodiment of the present application, the circuit board 11 is used as a daughter board, and after a chip power device, such as a chip power MOS transistor, is directly formed into a separate circuit board assembly (PCBA) on the circuit board 11 used as the daughter board, the product design can be completed without increasing the size of the motherboard, and the operation of the chip power device 12, such as a chip power MOS transistor, can be ensured to be within the rated temperature, and interference is not formed.
In further embodiments, the heat sink 30 may be made of a material that conducts heat well, such as aluminum, copper, etc.; and may be structurally configured to have a plurality of heat dissipating fins. In addition, the heat sink 30 and the heat conducting and insulating medium 20 may correspond to most of the area of the circuit board 11, so as to increase the heat dissipation area and improve the heat dissipation efficiency. It is noted that the heat sink 30 is different from the prior art chassis; that is, in a particular application, the circuit board heat dissipation structure 100 will be located in a chassis.
The embodiment of the utility model provides an electrical equipment is still provided, it can include the casing and according to above arbitrary circuit board heat radiation structure 100, circuit board heat radiation structure 100 is located in the casing. In some embodiments, the electrical device may be a high voltage device or a microwave device. The high-voltage equipment may be, for example, a motor, a transformer, a switchboard, a power transmission line, an insulator, or the like, having an operating voltage of 220V or more. The microwave device may be a device capable of generating microwaves, such as a microwave oven, a detection radar, a security check meter, or the like.
In other embodiments, the electrical device may also be a television, induction cooker, air conditioner, washing machine, refrigerator, or the like.
As can be understood from the above description, the circuit board heat dissipation structure 100 and the electrical apparatus using the circuit board heat dissipation structure 100 provided in the present application may have the following advantages as a whole: firstly, by arranging a heat conduction path and a heat conduction metal layer on the circuit board 11 and arranging the heat conduction insulating medium 20 and the radiator 30 which are in heat conduction connection, heat generated when the circuit board assembly 10 works can be quickly transferred to the radiator 30 for radiation, so that the radiation efficiency of the patch power device is improved; secondly, the circuit board heat radiation structure 100 that this application provided can regard as the substructure, namely move paster power tube and its drive circuit to the circuit board 11 as the daughter board, then carry out the built-up connection through for example pegging graft with the mother board again for can adopt the mode of mother-daughter board combination, reduce the mother board overall arrangement and the wiring degree of difficulty, can improve the radiating efficiency again when improving space utilization, satisfy the operating temperature requirement of paster power device of MOS pipe for example.
The aforesaid only does the embodiment of the utility model discloses a not consequently restriction the utility model discloses a patent range, all utilize the utility model discloses the equivalent structure or the equivalent flow transform that the specification and the drawing were held, or direct or indirect application is in other relevant technical field, all including on the same reason the utility model discloses a patent protection scope.
Claims (11)
1. A circuit board heat dissipation structure (100), comprising:
the circuit board assembly (10), the circuit board assembly (10) comprises a circuit board (11) and a patch power device (12) attached to a first surface of the circuit board (11), a second surface of the circuit board (11) opposite to the first surface is provided with a heat conduction metal layer, and a heat conduction path is formed between the heat conduction metal layer and the patch power device (12);
a thermally conductive and insulating medium (20), the thermally conductive and insulating medium (20) being connected to a second surface of the circuit board (11); and
the heat radiator (30) is connected to one side, far away from the circuit board assembly (10), of the heat-conducting insulating medium (20) and used for radiating heat of the circuit board assembly (10).
2. The circuit board heat dissipation structure (100) of claim 1,
the radiator (30) is provided with a positioning column (31), and the positioning column (31) is inserted in the heat-conducting insulating medium (20) and the circuit board (11) and used for positioning the heat-conducting insulating medium (20) and the circuit board (11).
3. The circuit board heat dissipation structure (100) of claim 2,
the length of the positioning column (31) is larger than the thickness of the heat-conducting insulating medium (20) and smaller than the total thickness of the heat-conducting insulating medium (20) and the circuit board (11).
4. The circuit board heat dissipation structure (100) of claim 2,
and the circuit board (11) is provided with a non-electroplating through hole (13) for the insertion and matching of the positioning column (31).
5. The circuit board heat dissipation structure (100) of claim 1,
the heat conduction insulating medium (20) is a ceramic substrate, and bonding layers are arranged between the radiator (30) and the ceramic substrate and between the ceramic substrate and the circuit board (11).
6. The circuit board heat dissipation structure (100) of claim 1,
the heat-conducting insulating medium (20) is a viscous heat-conducting insulating film.
7. The circuit board heat dissipation structure (100) of claim 1,
a heat dissipation pad is arranged on the first surface of the circuit board (11) and is welded with a pad of the patch power device (12); and is
The circuit board (11) is provided with a via hole which penetrates through the heat dissipation pad and the heat conduction metal layer, and a via hole metal layer is arranged in the via hole and serves as the heat conduction path; the via hole metal layer is in contact connection with the heat dissipation pad and the heat conduction metal layer.
8. The circuit board heat dissipation structure (100) of claim 7,
the via hole and the via hole metal layer are plated through holes.
9. The circuit board heat dissipation structure (100) of any one of claims 1 to 8,
the power devices on the circuit board (11) only comprise patch power devices (12).
10. The circuit board heat dissipation structure (100) of claim 9,
and the circuit board (11) is also provided with a driving circuit of the patch power device (12).
11. An electrical appliance, characterized in that it comprises a chassis and a circuit board heat dissipation structure (100) according to any of claims 1-10, the circuit board heat dissipation structure (100) being located inside the chassis.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202022890647.XU CN213847398U (en) | 2020-12-01 | 2020-12-01 | Circuit board heat radiation structure and electrical equipment |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202022890647.XU CN213847398U (en) | 2020-12-01 | 2020-12-01 | Circuit board heat radiation structure and electrical equipment |
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| Publication Number | Publication Date |
|---|---|
| CN213847398U true CN213847398U (en) | 2021-07-30 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN202022890647.XU Active CN213847398U (en) | 2020-12-01 | 2020-12-01 | Circuit board heat radiation structure and electrical equipment |
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| CN (1) | CN213847398U (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2024002324A1 (en) * | 2022-07-01 | 2024-01-04 | 北京比特大陆科技有限公司 | Heat sink, circuit board module and electronic device |
| WO2024124839A1 (en) * | 2022-12-16 | 2024-06-20 | 华为数字能源技术有限公司 | Power converter |
-
2020
- 2020-12-01 CN CN202022890647.XU patent/CN213847398U/en active Active
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2024002324A1 (en) * | 2022-07-01 | 2024-01-04 | 北京比特大陆科技有限公司 | Heat sink, circuit board module and electronic device |
| WO2024124839A1 (en) * | 2022-12-16 | 2024-06-20 | 华为数字能源技术有限公司 | Power converter |
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