Brick type power module packaging structure with shielding function and method

Abstract

The invention relates to a brick type power module packaging structure with a shielding function and a method. The brick type power module packaging structure comprises a cover plate, a printed circuit board and a metal base, the cover plate comprises a first insulating layer, a second insulating layer and a shielding metal layer, and the shielding metal layer is located between the first insulating layer and the second insulating layer; at least two sides of the first insulating layer are shorter than the corresponding sides of the shielding metal layer; a round hole is formed in the edge of the cover plate; the printed circuit board is combined with the cover plate through the PIN assembly penetrating through the round hole of the cover plate, and an insulation gap is arranged between the PIN assembly and the round hole. The metal base is connected with the cover plate through the metal surface, not attached to the first insulating layer, of the shielding metal layer. By adopting the structure, a good metal shielding effect on the power supply module can be achieved, on one hand, electromagnetic interference generated by the power supply module on external lines is reduced, on the other hand, external noise can be prevented from entering the power supply module, and the anti-electromagnetic interference capability of the power supply module is improved.

Description

Technical Field

[0001] The present application relates to the technical field of brick-type module power supplies, and in particular to a brick-type power supply module packaging structure and method with a shielding function. Background Art

[0002] In the field of brick-type module power supplies, commonly used packaging forms mainly include a single-sided metal base plus a five-sided plastic cover and a five-sided metal base plus a single-sided insulating cover (plastic or epoxy resin). Among them, the five-sided metal base solution has been increasingly used in recent years due to its better heat dissipation performance.

[0003] The module power supply is a strong noise source. When the power module based on the five-sided metal base and single-sided insulating cover is used in the system, the electromagnetic field generated by it is easy to interfere with the surrounding lines, especially when the control line is arranged at the bottom of the cover surface; in addition, the electromagnetic field can easily pass through the space coupling interference filter through the cover surface, causing EMI (Electromagnetic Interference) problems in the system. Summary of the invention

[0004] Based on this, it is necessary to provide a brick-type power module packaging structure and method with shielding function that can effectively suppress the electromagnetic radiation interference of the switching power supply and improve the EMI performance of the power module in order to address the above technical problems.

[0005] In a first aspect, the present application provides a brick-type power module packaging structure with a shielding function, the structure comprising a cover plate, a printed circuit board and a metal base; wherein:

[0006] The cover plate comprises a first insulating layer, a second insulating layer and a shielding metal layer, wherein the shielding metal layer is located between the first insulating layer and the second insulating layer and is bonded to the first insulating layer and the second insulating layer respectively; at least two of the four sides of the first insulating layer are shorter than the corresponding sides of the shielding metal layer, and the metal surface of the shielding metal layer that is not bonded to the first insulating layer is connected to the metal base; a circular hole is provided at the edge of the cover plate;

[0007] The printed circuit board is combined with the cover plate by passing the PIN needle assembly through the circular hole of the cover plate. When the PIN needle assembly passes through the circular hole on the cover plate, an insulating gap is provided between the PIN needle assembly and the circular hole.

[0008] The metal base is connected to the cover plate through the metal surface of the shielding metal layer that is not in contact with the first insulating layer.

[0009] In one embodiment, the area of ​​the second insulating layer is not less than the area of ​​the shielding metal layer.

[0010] In one embodiment, the metal base includes five sides.

[0011] In one of the embodiments, at least two supporting points are provided inside the five-sided metal base for supporting the printed circuit board to be placed horizontally inside the five-sided metal base.

[0012] In one embodiment, the area of ​​the printed circuit board is smaller than the bottom area of ​​the five-sided metal base.

[0013] In one of the embodiments, the method of connecting the metal base to the cover plate through the metal surface of the shielding metal layer that is not in contact with the first insulating layer includes bonding and screw connection.

[0014] In a second aspect, the present application also provides a brick-type power module packaging method with a shielding function, comprising:

[0015] A cover plate is generated, the cover plate comprises a first insulating layer, a second insulating layer and a shielding metal layer, wherein the shielding metal layer is located between the first insulating layer and the second insulating layer and is bonded to the first insulating layer and the second insulating layer respectively; at least two of the four sides of the first insulating layer are shorter than the corresponding sides of the shielding metal layer, and the metal surface of the shielding metal layer that is not bonded to the first insulating layer is connected to the metal base; a circular hole is provided at the edge of the cover plate;

[0016] A printed circuit board is provided, and the printed circuit board is combined with the cover plate by a PIN needle assembly passing through the circular hole of the cover plate, and an insulating gap is provided between the PIN needle assembly and the circular hole when the PIN needle assembly passes through the circular hole on the cover plate;

[0017] The metal base is connected to the cover plate through the metal surface of the shielding metal layer that is not in contact with the first insulating layer.

[0018] The brick-type power module packaging structure and method with shielding function are used to package the power module through a cover plate, a printed circuit board and a metal base, wherein the cover plate includes a first insulating layer, a second insulating layer and a shielding metal layer, wherein the shielding metal layer is located between the first insulating layer and the second insulating layer, and is respectively bonded to the first insulating layer and the second insulating layer; at least two of the four sides of the first insulating layer are smaller than the corresponding side lengths of the shielding metal layer, and the metal surface of the shielding metal layer that is not bonded to the first insulating layer is connected to the metal base; a circular hole is provided at the edge of the cover plate; the printed circuit board is combined with the cover plate through a PIN needle assembly passing through the circular hole of the cover plate, and when the PIN needle assembly passes through the circular hole on the cover plate, an insulating gap is provided between the PIN needle assembly and the circular hole; the metal base is connected to the cover plate through the metal surface of the shielding metal layer that is not bonded to the first insulating layer, abandoning the plastic packaging structure of the traditional power module, and can play a good metal shielding role for the power module, on the one hand reducing the electromagnetic interference generated by the power module to the external circuit, on the other hand preventing external noise from entering the power module, thereby improving the anti-electromagnetic interference capability of the power module. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a schematic diagram of a conventional brick-type power module in one embodiment;

[0020] Figure 2 A schematic diagram of the structure of a cover plate in a brick-type power module packaging structure with a shielding function in one embodiment;

[0021] Figure 3 A schematic top view of a cover plate structure in a brick-type power module packaging structure with a shielding function in one embodiment;

[0022] Figure 4 A schematic diagram of a brick-type power module packaging structure with a shielding function in one embodiment;

[0023] FIG5( a ) is an exploded view of a cover plate of a brick-type power module packaging structure with a shielding function in one embodiment;

[0024] FIG5( b ) is an exploded view of a cover plate of a brick-type power module packaging structure with a shielding function in one embodiment;

[0025] Figure 6 A schematic diagram of a brick-type power module packaging structure with a shielding function in yet another embodiment;

[0026] FIG. 7( a ) is an exploded view of a cover plate of a brick-type power module packaging structure with a shielding function in yet another embodiment;

[0027] FIG7( b ) is an exploded view of a cover plate of a brick-type power module packaging structure with a shielding function in yet another embodiment;

[0028] Figure 8 A schematic diagram of a brick-type power module packaging structure with a shielding function in another embodiment;

[0029] FIG9( a ) is an exploded view of a cover plate of a brick-type power module packaging structure with a shielding function in another embodiment;

[0030] FIG. 9( b ) is an exploded view of a cover plate of a brick-type power module packaging structure with a shielding function in another embodiment. DETAILED DESCRIPTION

[0031] In the field of brick-type module power supplies, the commonly used packaging forms mainly include a single-sided metal base plus a five-sided plastic cover and a five-sided metal base plus a single-sided insulating cover (plastic or epoxy resin). Among them, the five-sided metal base solution has been increasingly used in recent years due to its better heat dissipation performance. Figure 1As shown, it does not have a shielding function. 101 is the cover of the traditional brick power module, 102 is the PCBA (Printed Circuit Board Assembly) of the traditional brick power module, and 103 is the box of the traditional brick power module. The cover is made of non-metallic material, and the box has metal and non-metallic materials. The packaging structure does not have overall shielding functionality. The traditional brick power module is prone to generate interference through the non-shielded surface and cause EMI problems.

[0032] In order to reduce electromagnetic interference, in practice, the distance between the power module and the external signal line is usually increased, or a shielding layer is added to the circuit board where the external line is located to alleviate the line interference problem; the EMI performance is improved by shielding the EMI filter separately. However, these measures increase the complexity of the system, increase the cost, size and weight. Therefore, it is of great significance to develop a module power packaging solution with shielding function.

[0033] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0034] In an exemplary embodiment, a brick-type power module packaging structure with a shielding function is provided, which is used to package a power module and includes a cover plate, a printed circuit board and a metal base; wherein:

[0035] like Figure 2 As shown, the cover plate includes a first insulating layer 201, a second insulating layer 202 and a shielding metal layer 203, wherein the shielding metal layer 203 is located between the first insulating layer 201 and the second insulating layer 202, and is respectively bonded to the first insulating layer 201 and the second insulating layer 202; at least two of the four sides of the first insulating layer 201 are smaller than the corresponding side lengths of the shielding metal layer 203, and the metal surface of the shielding metal layer 203 that is not bonded to the first insulating layer 201 is connected to the metal base; a circular hole is provided at the edge of the cover plate;

[0036] The printed circuit board is combined with the cover plate by passing the PIN needle assembly through the circular hole of the cover plate. When the PIN needle assembly passes through the circular hole on the cover plate, an insulating gap is provided between the PIN needle assembly and the circular hole.

[0037] The metal base is connected to the cover plate through the metal surface of the shielding metal layer 203 that is not in contact with the first insulating layer 201 .

[0038] Optionally, the length of at least two of the four sides of the first insulating layer is smaller than the length of the corresponding sides of the shielding metal layer, and the exposed metal surface may be a continuous metal surface or an alternate metal surface.

[0039] Specifically, the material of the shielding metal layer includes pure copper, pure aluminum, aluminum alloy, and copper alloy.

[0040] Exemplarily, when the shielding metal layer is a copper layer, the printed circuit board is combined with the cover plate by passing the PIN needle assembly through the circular hole of the cover plate, and the conductive connection between the metal base and the cover plate includes the metal base being connected to the cover plate through the copper surface of the copper layer that is not bonded to the first insulating layer. Optionally, the copper layer width is 0.20mm-2.00mm, including 0.20mm, 0.25mm, 0.30mm, 0.35mm, 0.40mm, 0.45mm, 0.50mm, 0.55mm, 0.60mm, 0.65mm, 0.70mm, 0.75mm, 0.80mm, 0.85mm, 0.90mm, 0.95mm, 1.00mm, 1.05mm, 1.10mm, 1.15mm, 1.20mm, 1.25mm, 1.30mm, 1.35mm, 1.40mm, 1.45mm, 1.50mm, 1.55mm, 1.60mm, 1.65mm, 1.70mm, 1.75mm, 1.80mm, 1.85mm, 1.90mm, 1.95mm, and 2.00mm.

[0041] In an exemplary embodiment, the area of ​​the second insulating layer is not less than the area of ​​the shielding metal layer; that is, the area of ​​the second insulating layer is greater than or equal to the area of ​​the shielding metal layer. Exemplarily, the second insulating layer is completely in contact with the shielding metal layer.

[0042] In an exemplary embodiment, the cover plate includes two long sides and two wide sides parallel to each other, wherein the length of the long sides is greater than the length of the wide sides, the circular hole of the cover plate can be set at any position of the cover plate, and the corresponding PIN needle is located at any position of the printed circuit board.

[0043] Specifically, the cover plate is laminated and pressed in multiple layers, with the upper and lower outermost layers being insulating layers, namely the first insulating layer and the second insulating layer, and the shielding metal layer in the middle. The lower insulating layer is completely bonded to the shielding metal layer, namely the second insulating layer is completely bonded to the shielding metal layer. The upper insulating layer, namely the first insulating layer, is bonded to the shielding metal layer, but the sizes are different. A circle of shielding metal layer is exposed around the first insulating layer, and the exposed part of the shielding metal layer can be installed with the five-sided metal base to achieve functions such as insulation and metal shielding.

[0044] Furthermore, a circular hole can be provided at any position on the cover plate. The circular hole is for allowing the PIN on the printed circuit board to pass through when the cover plate and the printed circuit board are installed. At the same time, the size of the circular hole sets an insulating gap to ensure that the PIN has insulation when passing through the circular hole.

[0045] Exemplarily, the width of the insulating gap is 0.15mm-2.00mm; Exemplarily, the diameter of the insulating gap is 0.15mm, 0.20mm, 0.25mm, 0.30mm, 0.35mm, 0.40mm, 0.45mm, 0.50mm, 0.55mm, 0.60mm, 0.65mm, 0.70mm, 0.75mm, 0.80mm, 0.85mm, 0.90mm, 0. .95mm, 1.00mm, 1.05mm, 1.10mm, 1.15mm, 1.20mm, 1.25mm, 1.30mm, 1.35mm, 1.40mm, 1.45mm, 1.50mm, 1.55mm, 1.60mm, 1.65mm, 1.70mm, 1.75mm, 1.80mm, 1.85mm, 1.90mm, 1.95mm, 2.00mm.

[0046] In an exemplary embodiment, in the structure of the packaged power module, the printed circuit board also includes a PIN needle assembly, which mainly includes PIN needles installed on the bottom surface of the printed circuit board to achieve signal and power transmission.

[0047] In an exemplary embodiment, circuit components are arranged on the printed circuit board. For example, circuit components such as a transformer, a control chip, a power switch tube, a resistor, an inductor, and a capacitor are arranged on the printed circuit board.

[0048] Specifically, the printed circuit board in the structure of the packaged power module includes a bare PCB board and a transformer and all other components on the bare PCB board, such as a control chip, a power switch tube, a resistor, a capacitor, and the like.

[0049] In an exemplary embodiment, the metal base includes five sides.

[0050] In an exemplary embodiment, at least two supporting points are provided inside the five-sided metal base for supporting the printed circuit board to be placed horizontally inside the five-sided metal base. Optionally, the supporting points are arc-shaped or column-shaped.

[0051] In an exemplary embodiment, the printed circuit board area is smaller than the bottom area of ​​the five-sided metal base.

[0052] In an exemplary embodiment, the method of connecting the metal base to the cover plate through the metal surface of the shielding metal layer that is not in contact with the first insulating layer includes bonding or screw connection.

[0053] Optionally, the conductive adhesive is covered on the exposed metal surface of the shielding metal layer that is not bonded to the first insulating layer or the metal base, and then bonded; screw holes are punched on the metal base and the cover, and the metal base and the cover are connected with screws.

[0054] Optionally, the shielding metal layer and the metal base are connected by bonding with conductive adhesive or locking with screws, and the exposed portion of the shielding metal layer can also be clamped and installed with the five-sided metal base.

[0055] For example, a top view of a brick-type power module cover structure with a shielding function is shown in FIG. Figure 3 As shown, the printed circuit board includes a bare PCB board and circuit components on the bare PCB board. The bare multilayer PCB board includes transformers, control chips, power switch tubes, resistors and capacitors and many other components. The bare PCB board is visible from the side. The copper plating is the part of the shielding metal layer that is not attached to the first insulating layer. The transformer core of the power module is wrapped inside the packaging material to achieve good electromagnetic shielding function. Among them, the bare PCB board is finally packaged inside the brick-type power module by a five-sided metal base and a cover plate. In particular, the transformer core on the bare PCB board is also packaged in a closed metal power shielding body to achieve good electromagnetic shielding function.

[0056] In this embodiment, the structure of the power module encapsulated by the printed circuit board, the cover plate and the five-sided metal base can achieve a good electromagnetic shielding effect. The power module includes a printed circuit board, a cover plate and a metal base. The printed circuit board is distributed on the bottom plate of the power module. An opening is designed on one side of the bottom plate of the five-sided metal base, and the remaining multiple sides are the outer shell of the power module structure, which serves as a heat dissipation material and also as the "outer shell" of the power module to achieve a metal shielding function.

[0057] In an exemplary embodiment, Figure 4 As shown, a brick-type power module packaging structure with a shielding function is provided, wherein 401 is a cover plate of the brick-type power module packaging structure with a shielding function, 402 is a PCBA of the brick-type power module packaging structure with a shielding function, and 403 is a box body of the brick-type power module packaging structure with a shielding function; further, the exploded view of the cover plate of the brick-type power module packaging structure with a shielding function is shown in Figures 5(a) and 5(b), wherein 501 is a surface non-metallic material, 502 is an inner metal material, 503 is an inner laminated metal material, and 504 is a surface non-metallic material, and the inner and surface metals are interconnected, wherein the surface layer is the first insulating layer and the second insulating layer, the inner layer is the shielding metal layer, and the inner laminated metal material is the metal surface of the shielding metal layer that is not laminated to the first insulating layer;

[0058] In yet another exemplary embodiment, Figure 6As shown, a brick-type power module packaging structure with a shielding function is provided, wherein 601 is a screw, 602 is a cover plate of the brick-type power module packaging structure with a shielding function, 603 is a PCBA of the brick-type power module packaging structure with a shielding function, and 604 is a box body of the brick-type power module packaging structure with a shielding function, wherein the thread is inside the screw hole corresponding to the screw; further, the cover plate decomposition diagram is shown in Figures 7(a) and 7(b), 701 is a surface non-metallic material, 702 is an inner layer bonded metal material, 703 is an inner layer metal material, 704 is a surface non-metallic material, the inner layer and the surface metal are interconnected, wherein the surface layer is the first insulating layer and the second insulating layer, the inner layer is the shielding metal layer, and the inner layer bonded metal material is the metal surface of the shielding metal layer that is not bonded to the first insulating layer;

[0059] In another exemplary embodiment, Figure 8 As shown, a brick-type power module packaging structure with a shielding function is provided, wherein 801 is a screw, 802 is a cover plate of the brick-type power module packaging structure with a shielding function, 803 is a PCBA of the brick-type power module packaging structure with a shielding function, and 804 is a box body of the brick-type power module packaging structure with a shielding function, wherein the screw hole in which the screw is embedded is a smooth through hole; further, the cover plate decomposition diagram is shown in Figures 9(a) and 9(b), 901 is a surface non-metallic material, 902 is an inner layer bonded metal material, 903 is an inner layer metal material, 904 is a surface non-metallic material, the inner layer and the surface metal are interconnected, wherein the surface layer is the first insulating layer and the second insulating layer, the inner layer is the shielding metal layer, and the inner layer bonded metal material is the metal surface of the shielding metal layer that is not bonded to the first insulating layer;

[0060] In the above-mentioned brick-type power module packaging structure with shielding function, the cover plate is a combination of metal and non-metal, which can not only play the safety and safety compliance of non-metallic materials, but also has the functionality of metal shielding. Because the box body is a pentahedral metal material, the packaging structure has the functionality of overall shielding.

[0061] The power module structure of the cover plate, printed circuit board and metal packaging shell provided in the above embodiment, the PCB bare board is placed on the bottom plate of the power module, and the other five-sided metal packaging shell is set, abandoning the plastic packaging structure of the traditional power module, which can play a good electromagnetic shielding role for the power module. The unique PCB bare board structure is suitable for the brick-type power module in this application by reasonably optimizing the copper plating method of the PCB bare board, that is, the cover plate design with a shielding metal layer sandwiched between the first insulating layer and the second insulating layer. The shielding metal layer that is not covered by the first insulating layer makes the edge of the PCB bare board copper-plated and conductively connected to the metal base to achieve efficient electromagnetic shielding effect.

[0062] In an exemplary embodiment, a brick-type power module packaging method with a shielding function is provided, comprising:

[0063] A cover plate is generated, the cover plate comprises a first insulating layer, a second insulating layer and a shielding metal layer, wherein the shielding metal layer is located between the first insulating layer and the second insulating layer and is bonded to the first insulating layer and the second insulating layer respectively; at least two of the four sides of the first insulating layer are shorter than the corresponding sides of the shielding metal layer, and the metal surface of the shielding metal layer that is not bonded to the first insulating layer is connected to the metal base; a circular hole is provided at the edge of the cover plate;

[0064] A printed circuit board is provided, and the printed circuit board is combined with the cover plate by a PIN needle assembly passing through the circular hole of the cover plate, and an insulating gap is provided between the PIN needle assembly and the circular hole when the PIN needle assembly passes through the circular hole on the cover plate;

[0065] The metal base is connected to the cover plate through the metal surface of the shielding metal layer that is not in contact with the first insulating layer.

[0066] The packaging structure of the power module in this embodiment adopts a five-sided metal base, a printed circuit board and a cover plate. A shielding metal layer is provided in the middle of the cover plate. The exposed metal surface of the shielding metal layer is connected to the metal base, so that the metal shielding of the entire power module can be achieved and the cover plate surface can be made insulating.

[0067] In an exemplary embodiment, the packaging structure and packaging method in the present application can also be used to package a brick-type EMI filter module, that is, the power module in the present application can be replaced with an EMI filter module.

[0068] For those skilled in the art, several modifications and improvements can be made without departing from the concept of the present application, and these modifications and improvements are all within the scope of protection of the present application. Therefore, the scope of protection of the present application shall be subject to the attached claims.

Claims

1. A brick-type power module packaging structure with shielding function, characterized in that: The structure comprises a cover plate, a printed circuit board and a metal base; wherein: The cover plate comprises a first insulating layer, a second insulating layer and a shielding metal layer, wherein the shielding metal layer is located between the first insulating layer and the second insulating layer and is bonded to the first insulating layer and the second insulating layer respectively; at least two of the four sides of the first insulating layer are shorter than the corresponding sides of the shielding metal layer, and the metal surface of the shielding metal layer that is not bonded to the first insulating layer is connected to the metal base; a circular hole is provided at the edge of the cover plate; The printed circuit board is combined with the cover plate by passing the PIN needle assembly through the circular hole of the cover plate. When the PIN needle assembly passes through the circular hole on the cover plate, an insulating gap is provided between the PIN needle assembly and the circular hole. The metal base is connected to the cover plate through the metal surface of the shielding metal layer that is not in contact with the first insulating layer.

2. The structure according to claim 1, characterized in that: The area of ​​the second insulating layer is not less than the area of ​​the shielding metal layer.

3. The structure according to claim 2, characterized in that: The metal base includes five sides.

4. The structure according to claim 3, characterized in that At least two supporting points are arranged inside the five-sided metal base for supporting the printed circuit board to be placed horizontally inside the five-sided metal base.

5. The structure according to claim 4, characterized in that: The area of ​​the printed circuit board is smaller than the bottom area of ​​the five-sided metal base.

6. The structure according to claim 5, characterized in that The method of connecting the metal base with the cover plate through the metal surface of the shielding metal layer that is not in contact with the first insulating layer includes bonding and screw connection.

7. A brick-type power module packaging method with shielding function, characterized in that: The method comprises: A cover plate is generated, the cover plate comprising a first insulating layer, a second insulating layer and a shielding metal layer, wherein the shielding metal layer is located between the first insulating layer and the second insulating layer and is bonded to the first insulating layer and the second insulating layer respectively; at least two of the four sides of the first insulating layer are shorter than the corresponding sides of the shielding metal layer, and the metal surface of the shielding metal layer that is not bonded to the first insulating layer is connected to the metal base; and a circular hole is provided at the edge of the cover plate; A printed circuit board is provided, wherein the printed circuit board is combined with the cover plate by a PIN needle assembly passing through the circular hole of the cover plate, and an insulating gap is provided between the PIN needle assembly and the circular hole when the PIN needle assembly passes through the circular hole on the cover plate; The metal base is connected to the cover plate through the metal surface of the shielding metal layer that is not in contact with the first insulating layer.

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