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CN-121985826-A - Power module

CN121985826ACN 121985826 ACN121985826 ACN 121985826ACN-121985826-A

Abstract

The invention discloses a power module which comprises a power chip, an integrated bottom plate structure and a preformed lead terminal combined structure. The surface copper layer of the integrated bottom plate structure is provided with a chip mounting area and an electric connection pattern of a circuit topology, and the bottom surface of the copper bottom plate is a radiating surface. The power chip is mounted in the chip mounting area. The lead terminals of the preformed lead terminal combination structure penetrate through the first PCB board and are welded and fixed through copper foils arranged on the first PCB board, and the copper foils also realize electric connection between the corresponding lead terminals. The terminal inner section of each lead terminal has a bent structure and terminal legs at the ends. The terminal outer side section of each lead terminal is parallel to the width edge of the copper bottom plate and extends to the outer side of the length edge of the copper bottom plate, and an external connection structure fixedly connected with the driving PCB is formed, and the end face and the heat dissipation surface of the external connection structure are of a vertical structure so as to realize 90-degree installation. The invention can save installation space, optimize heat dissipation path and improve assembly efficiency.

Inventors

  • Request for anonymity

Assignees

  • 海南亿塔科技有限公司

Dates

Publication Date
20260505
Application Date
20260202

Claims (17)

  1. 1. The power module is characterized by comprising a power chip, an integrated bottom plate structure and a preformed lead terminal combined structure; the integrated bottom plate structure comprises a copper bottom plate with an insulating heat conducting layer and a surface copper layer formed on the top surface of the insulating heat conducting layer; the surface copper layer is provided with an electric connection pattern of a chip mounting area and a circuit topology, and the insulating heat conduction layer is used for electrically insulating the copper bottom plate and the surface copper layer; The bottom surface of the copper bottom plate is a radiating surface, and the insulating heat conducting layer and the copper bottom plate form a heat conducting channel between the bottom surface of the surface copper layer and the radiating surface; The power chip is attached to the chip attaching area, and the radiating surface is used for fixedly mounting a radiator; The preformed lead terminal assembly structure comprises a plurality of lead terminals and a first PCB board for fixing the lead terminals; each lead terminal passes through the first PCB and is welded and fixed through a copper foil arranged on the first PCB, and the copper foil also realizes the electric connection between the corresponding lead terminals; Each lead terminal comprises a terminal outer section and a terminal inner section which are positioned at two sides of the first PCB; each terminal inner section is provided with a bending structure and a terminal welding leg at the end part, and the terminal welding leg is used for being welded on the welding position of the surface copper layer; The width sides of the terminal outer side sections and the copper bottom plate are parallel, the end parts of the terminal outer side sections extend to the outer side of the length side of one side of the copper bottom plate, the terminal outer side sections form an external connection structure fixedly connected with the driving PCB, and the end faces of the external connection structure and the heat dissipation surface are in a vertical structure so as to realize 90-degree installation.
  2. 2. The power module of claim 1, further comprising an injection molded housing that encapsulates the power module and exposes the cooling surface and the connection structure.
  3. 3. The power module of claim 2, wherein the upper and lower sides of the first PCB are both long sides, the lower side of the first PCB is in contact with the top surface of the surface copper layer, and grooves are formed in the upper and lower sides of the first PCB and fixedly combined with the injection molding shell through the grooves.
  4. 4. The power module of claim 1, wherein edges of the insulating and thermally conductive layer and the copper base plate are aligned, and edges of the surface copper layer are located inward of edges of the insulating and thermally conductive layer; the ratio of the length to the width of the copper bottom plate is more than 3:1.
  5. 5. The power module of claim 1, wherein the copper base plate comprises C10300 pure copper and the surface copper layer comprises C10300 pure copper.
  6. 6. The power module of claim 5, wherein the insulating and heat conducting layer is made of a material with a thermal conductivity of 15W/mK or more, and the peel strength between the insulating and heat conducting layer and the surface copper layer is > =15N/cm.
  7. 7. The power module of claim 1, wherein the lead terminal is made of T2 copper or copper alloy meeting the requirement of mounting strength.
  8. 8. The power module as set forth in claim 7, wherein the type of copper alloy constituting the lead terminal includes C19400.
  9. 9. The power module of claim 1, wherein the mounting structure of the power chip is a solder brazing structure or a nano silver sintering structure.
  10. 10. The power module as set forth in claim 9, wherein the front electrode of the power chip is further connected to the corresponding electrical connection pattern of the surface copper layer by bonding wires.
  11. 11. The power module of claim 1, wherein the welding process between the terminal pins and the surface copper layer comprises an ultrasonic welding process, a laser welding process, or a soldering process.
  12. 12. The power module of claim 1, wherein the pattern of the copper foil is configured according to the structure of the circuit topology; The number and the positions of the lead terminals are set according to the circuit topology structure, and the lead terminals corresponding to the terminal welding pins connected with the same electric connection pattern in the circuit topology are also connected through the corresponding copper foil patterns; the external connection structure is arranged according to the connection requirement with the drive PCB, and a safe working insulation space is reserved between the external sections of the terminals in the external connection structure.
  13. 13. The power module of claim 12, wherein the circuit topology is determined by an electrical system device to which the power module is applied.
  14. 14. The power module as recited in claim 13 wherein said electrical system equipment includes a plurality of inverters of different power.
  15. 15. The power module of claim 1, wherein the integrated backplane structure further has mounting holes located outside the width edges of the surface copper layer and through the insulating thermally conductive layer and the copper backplane.
  16. 16. The power module of claim 15, wherein the spacing of the mounting holes and the length and width of the integrated bottom structure are set according to the magnitude of the output current.
  17. 17. The power module as set forth in claim 12, wherein said external connection structure has two-layered arrangement of said terminal outer sections, and wherein the pitch between said lead terminals satisfies the requirements of insulation gap and creepage distance prescribed by IEC60664-1 standard.

Description

Power module Technical Field The invention relates to the field of semiconductor devices, in particular to a power module. Background Power modules are the core semiconductor devices for all electrical systems, power transmission and control, and are the heart of industrial systems and numerous electrical systems. As shown in fig. 1, a circuit diagram of a typical power module is shown, and an input rectifier bridge 101, an output inverter bridge 103 and a brake braking unit 102 are included in the circuit diagram, which is a typical circuit topology applied to an industrial frequency converter. As shown in fig. 2, a conventional standard power module is provided with a heat sink and a driving PCB, and a chassis 201 of the standard power module is typically mounted on a surface of the heat sink 202. Since the electrode terminals 203 are perpendicular to the bottom plate of the power module, the drive PCB 204 must be parallel to the module bottom surface, i.e., the surface of the heat sink 202 when the drive PCB 204 is mounted. Such a configuration occupies vertical space in the system and is disadvantageous in terms of the development requirements for reducing the system volume and increasing the power density. Disclosure of Invention The invention aims to solve the technical problem of providing a power device which can realize 90-degree installation, save installation space, optimize a heat dissipation path and improve assembly efficiency. In order to solve the technical problems, the power module provided by the invention comprises a power chip, an integrated bottom plate structure and a preformed lead terminal combined structure. The integrated bottom plate structure comprises a copper bottom plate with an insulating heat conducting layer and a surface copper layer formed on the top surface of the insulating heat conducting layer. The surface copper layer is provided with an electric connection pattern of a chip mounting area and a circuit topology, and the insulating heat conduction layer is used for electrically insulating the copper bottom plate and the surface copper layer. The bottom surface of the copper bottom plate is a radiating surface, the insulating heat conducting layer and the copper bottom plate form a heat conducting channel between the bottom surface of the surface copper layer and the radiating surface, and the thickness of the copper bottom plate is larger than that of the surface copper layer. The power chip is attached to the chip attaching area, and the radiating surface is used for fixedly mounting a radiator. The preformed lead terminal assembly structure includes a plurality of lead terminals and a first PCB for fixing the lead terminals. Each lead terminal penetrates through the first PCB and is welded and fixed through copper foils arranged on the first PCB, and the copper foils also realize electric connection between the corresponding lead terminals. Each lead terminal comprises a terminal outer side section and a terminal inner side section which are positioned on two sides of the first PCB. Each of the terminal inner sections has a bent structure and has terminal legs at ends for welding to the welding locations of the surface copper layers. The width sides of the terminal outer side sections and the copper bottom plate are parallel, the end parts of the terminal outer side sections extend to the outer side of the length side of one side of the copper bottom plate, the terminal outer side sections form an external connection structure fixedly connected with the driving PCB, and the end faces of the external connection structure and the heat dissipation surface are in a vertical structure so as to realize 90-degree installation. The power module is further improved by further comprising an injection molding shell, wherein the injection molding shell covers the power module and exposes the radiating surface and the connecting structure. The upper edge and the lower edge of the first PCB are both length edges, the lower edge of the first PCB is in contact with the top surface of the surface copper layer, and grooves are formed in the upper edge and the lower edge of the first PCB and are fixedly combined with the injection molding shell through the grooves. A further improvement is that the edges of the insulating and heat conducting layer and the copper bottom plate are aligned, and the edge of the surface copper layer is located inside the edge of the insulating and heat conducting layer. The ratio of the length to the width of the copper bottom plate is more than 3:1. The copper base plate is further improved in that the material of the copper base plate comprises C10300 pure copper, and the material of the surface copper layer is C10300 pure copper. The insulating heat conduction layer is made of a material with the heat conductivity of more than or equal to 15W/mK, and the peeling strength between the insulating heat conduction layer and the surface copper layer is > =15