Power module lead frame and power module

Abstract

The utility model discloses a power module lead frame and a power module, and relates to the semiconductor device technology field, the lead frame comprises a frame body, connecting ribs, a plurality of power boards and a plurality of power pins, the plurality of power boards and the plurality of power pins are arranged in the frame body through the connecting ribs, the power pins are arranged corresponding to the power board; one surface of the power board is a power chip setting area used for installing a power chip, and the other surface of the power board is a semi-etching area used for power input and power output; and the plurality of power pins are used for connecting the power chip arranged on the power chip setting area with an external circuit. According to the utility model, the resistance value of the power module during power transmission can be reduced, the current transmission efficiency can be improved, the performance of the power module is improved, and the reliability of the power module is improved.

Description

Technical Field

[0001] This utility model relates to the field of power semiconductor device technology, and in particular to a power module lead frame and a power module. Background Technology

[0002] As a chip carrier for integrated circuits, the lead frame is a key structural component that uses bonding materials (gold wire, aluminum wire, copper wire) to achieve electrical connection between the internal circuit leads of the chip and the external leads, forming an electrical circuit. It acts as a bridge connecting to external wires. Most semiconductor integrated circuits require the use of lead frames, which are an important basic material in the electronics and information industry.

[0003] With the increasing demand for high integration and miniaturization of chips, there is a desire to improve the packaging structure of power modules. In the packaging structure of a power module, the leadframe includes a base island for carrying the chip, inner pins providing internal electrical connections to the chip, and outer pins providing external electrical connections to the chip. After electrically connecting the chip to the inner pins of the leadframe, a molding compound is used to encapsulate the leadframe and the chip, and then the outer pins of the leadframe are used for external electrical connections. However, when power modules operate in high-frequency pulse or high-voltage fields, their heat dissipation performance and current confluence are poor, their overcurrent capacity is weak, their stray inductance is large, and their device reliability is low. Furthermore, the encapsulation of the power module is poor, making it easy to burn out the power devices. Since the operating performance of the power module is closely related to the leadframe, further adjustments to the leadframe are needed to improve the reliability of the power module during operation, resulting in more stable operation.

[0004] In the process of realizing this utility model, the inventors discovered that the prior art has at least the following problems:

[0005] Existing power modules exhibit low reliability when operating in high-frequency pulse or high-voltage environments. Utility Model Content

[0006] The purpose of this invention is to provide a power module lead frame and a power module to solve the technical problem of low reliability of power modules when operating in high-frequency pulse or high-voltage fields. The preferred technical solutions provided by this invention and their various technical effects are detailed below.

[0007] To achieve the above objectives, the present invention provides the following technical solution:

[0008] In a first aspect, this utility model provides a power module lead frame, including a frame body, connecting ribs, multiple power boards and multiple power pins, wherein the multiple power boards and the multiple power pins are all disposed in the frame body through connecting ribs, and the power pins are disposed corresponding to the power boards;

[0009] One side of the power board is a power chip mounting area for mounting power chips, and the other side is a semi-etched area for power input and power output.

[0010] The plurality of power pins are used to connect the power chip located on the power chip setting area to an external circuit.

[0011] Optionally, the semi-etched area includes an auxiliary fastening surface and a power contact surface; the auxiliary fastening surface is located around the power contact surface; the power contact surface is not covered by the encapsulating colloid during encapsulation and is used for DC input and AC output; the auxiliary fastening surface is covered by the encapsulating colloid during encapsulation.

[0012] Optionally, the etching depth of the auxiliary fastening surface is 1 / 4 to 1 / 2 of the thickness of the power board.

[0013] Optionally, the power board includes an upper bridge power board and a lower bridge power board, which are laterally connected to the frame body via transverse connecting ribs.

[0014] The power pins include multiple upper bridge power pins and multiple lower bridge power pins. The upper bridge power pins and lower bridge power pins extend inward from the edge of the frame body through longitudinal connecting ribs. The upper bridge power pins and lower bridge power pins are located on the sides of the upper bridge power board and the lower bridge power board, respectively.

[0015] Optionally, the upper bridge power pins are all narrow-body power pins of the same size; the lower bridge power pins are narrow-body power pins and wide-body power pins spaced apart.

[0016] Optionally, the wide-body power pin is provided with an auxiliary fastening groove, which is located on the same side as the half-etched area of ​​the power board. The auxiliary fastening groove is used to fasten the wide-body power pin to the encapsulation material when the power module is packaged.

[0017] Optionally, the depth of the auxiliary fastening groove is 1 / 4 to 1 / 2 of the thickness of the wide-body power pin.

[0018] Optionally, the ratio of the number of power chips to the number of power pins is 1:2.

[0019] Secondly, the present invention also provides a power module, including the power module lead frame described in any of the above claims, and further including a power chip, an electrical connector, and an encapsulating colloid; the power chip is disposed on the power board, and the electrical connector connects the power chip to the power pin to realize its electrical function; the encapsulating colloid is used to encapsulate the power chip, the power pin, and the electrical connector.

[0020] Optionally, the electrical connector is made of aluminum wire, copper wire, gold wire, silver wire, aluminum strip, or copper strip; the power chip is a MOSFET; and the encapsulating colloid is epoxy resin or silicone gel.

[0021] Implementing one of the above-described technical solutions of this utility model has the following advantages or beneficial effects:

[0022] This utility model provides a frame body, connecting ribs, multiple power boards, and multiple power pins. The power boards and power pins are all mounted within the frame body via the connecting ribs, with the power pins corresponding to the power boards. One side of each power board is a power chip mounting area for mounting power chips, and the other side is a semi-etched area for power input and output. The multiple power pins connect the power chips mounted on the power chip mounting area to external circuits. After the power chips are mounted on the lead frame and electrically connected to the power pins, encapsulation is required to form a power module. During encapsulation, the semi-etched area on the power board is not completely encapsulated by the encapsulating material, facilitating power input and output while also promoting heat dissipation. This also reduces the resistance of the power module during power transmission, improving current transmission efficiency, enhancing the performance and reliability of the power module. Attached Figure Description

[0023] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. In the drawings:

[0024] Figure 1 This is a first-view schematic diagram of the overall structure of the lead frame in Embodiment 1 of this utility model;

[0025] Figure 2 This is a second-view schematic diagram of the overall structure of the lead frame in Embodiment 1 of this utility model;

[0026] Figure 3 This is a first-view schematic diagram of the lead frame produced in batches according to Embodiment 1 of this utility model;

[0027] Figure 4 This is a second-view schematic diagram of the lead frame mass-produced in Embodiment 1 of this utility model;

[0028] Figure 5 This is a first-view schematic diagram of the overall structure of the power module in Embodiment 2 of this utility model;

[0029] Figure 6 This is a second-view schematic diagram of the overall structure of the power module in Embodiment 2 of this utility model;

[0030] Figure 7 This is a schematic diagram of the structure of the power module in Embodiment 2 of this utility model, which uses metal wires to connect the power chip and the power pins;

[0031] Figure 8 This is a schematic diagram of the structure of the power module in Embodiment 2 of this utility model, which uses a metal strip to connect the power chip and the power pin;

[0032] Figure 9 This is a schematic diagram of the structure of the power module mass-produced in Embodiment 2 of this utility model;

[0033] In the diagram: 1. Frame body; 2. Connecting ribs; 21. Transverse connecting ribs; 22. Longitudinal connecting ribs; 3. Power board; 31. Upper bridge power board; 32. Lower bridge power board; 321. First lower bridge power board; 322. Second lower bridge power board; 33. Power contact surface; 34. Auxiliary fastening surface; 4. Power pins; 41. Upper bridge power pins; 42. Lower bridge power pins; 43. Narrow-body power pins; 44. Wide-body power pins; 45. Auxiliary fastening grooves; 5. Power chip; 6. Electrical connectors; 7. Encapsulating colloid. Detailed Implementation

[0034] To make the objectives, technical solutions, and advantages of this utility model clearer, various exemplary embodiments described below will be referenced to the accompanying drawings, which form part of the exemplary embodiments, illustrating various exemplary embodiments that may be adopted to implement this utility model. Unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this disclosure. It should be understood that they are merely examples of processes, methods, and apparatuses consistent with some aspects of this utility model disclosed as detailed in the appended claims, and other embodiments may be used, or structural and functional modifications may be made to the embodiments listed herein without departing from the scope and spirit of this utility model.

[0035] In the description of this utility model, it should be understood that the terms "center," "longitudinal," "lateral," etc., indicate the orientation or positional relationship based on the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the referred element must have a specific orientation, or be constructed and operated in a specific orientation. The terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. The term "multiple" means two or more. The terms "connected" and "linked" should be interpreted broadly, for example, they can be fixed connections, detachable connections, integral connections, mechanical connections, electrical connections, communication connections, direct connections, indirect connections through an intermediate medium, and can be the internal connection of two elements or the interaction relationship between two elements. The term "and / or" includes any and all combinations of one or more of the related listed items. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0036] To illustrate the technical solution described in this utility model, specific embodiments are described below, showing only the parts related to the embodiments of this utility model.

[0037] Example 1:

[0038] like Figure 1-2 As shown, this utility model provides a power module lead frame, including a frame body 1, connecting ribs 2, multiple power boards 3, and multiple power pins 4. The multiple power boards 3 and multiple power pins 4 are all disposed within the frame body 1 via the connecting ribs 2, and the power pins 4 are correspondingly disposed with respect to the power boards 3. Figure 1 As shown, one side of power board 3 is the power chip mounting area, used to install power chips, such as... Figure 2 As shown, the other side is a semi-etched area for power input and power output; multiple power pins 4 are used to connect the power chip located on the power chip setting area to external circuitry.

[0039] Specifically, multiple power boards 3 and multiple power pins 4 are all set within the frame body 1 via connecting ribs 2. The frame body 1 is used to support the multiple power boards 3 and multiple power pins 4. The power boards 3 have two sides, such as... Figure 1 As shown, one side is a power chip setting area for mounting power chips. Power chips can be set in this area, and after setting, they can be connected to power pins 4 corresponding to those on power board 3 via bonding wires. For example... Figure 2 As shown, the other side of the power board 3 is a semi-etched area after semi-etching. The semi-etched area after etching is not on the same plane as the power board 3 itself. The etched part of the semi-etched area is recessed downward on the power board 3. The semi-etched area is used for power input and power output.

[0040] In this embodiment, since multiple power boards 3 are provided, multiple corresponding power pins 4 are also provided, which facilitates the connection of the power chip installed on the power chip setting area with the external circuit.

[0041] It should be noted that after the power chip is installed on the lead frame and electrically connected to the power pin 4, it needs to be packaged to form a power module. During the packaging process, the upper half of the etched area of ​​the power board 3 will not be completely encapsulated by the encapsulating glue. This facilitates power input and output, as well as heat dissipation. It also reduces the resistance of the power module during power transmission, thereby improving current transmission efficiency, enhancing the performance and reliability of the power module.

[0042] In this embodiment, the frame body 1, power board 3, and power pin 4 have the same thickness.

[0043] As an optional implementation method, such as Figure 1 As shown, the power board 3 includes an upper bridge power board 31 and a lower bridge power board 32, which are laterally connected to the frame body 1 via transverse connecting ribs 21; the power pins 4 include multiple upper bridge power pins 41 and multiple lower bridge power pins 42, which extend inward from the edge of the frame body 1 via longitudinal connecting ribs 22, and are located on the sides of the upper bridge power board 31 and the lower bridge power board 32 respectively.

[0044] Specifically, the power board 3 includes an upper bridge power board 31 and a lower bridge power board 32, and the power pins 4 include multiple upper bridge power pins 41 and multiple lower bridge power pins 42. The upper bridge power board 31 and the lower bridge power board 32 are connected to the frame body 1 by transverse connecting ribs 21, and the upper bridge power board 31 and the lower bridge power board 32 are arranged side by side. The upper bridge power pins 41 and the lower bridge power pins 42 extend inward from the upper and lower edges of the frame body 1 by longitudinal connecting ribs 22. The upper bridge power pins 41 are corresponding to the upper bridge power board 31 and are located on the side of the upper bridge power board 31, and the lower bridge power pins 42 are corresponding to the lower bridge power board 32 and are located on the side of the lower bridge power board 32.

[0045] like Figure 1 As shown, there are multiple upper-bridge power pins 41 and multiple lower-bridge power pins 42. Specifically, the number of upper-bridge power pins 41 and lower-bridge power pins 42 corresponds to the number of chips on the upper-bridge power board 31 and lower-bridge power board 32, with a power pin to power chip ratio of 2:1. For example, if two power chips are required on the upper-bridge power board 31, then the corresponding number of upper-bridge power pins 41 will be four.

[0046] like Figure 1 As shown, the lower-bridge power board 32 includes a first lower-bridge power board 321 and a second lower-bridge power board 322, which are arranged in parallel. The lower-bridge power pins 42 include a first lower-bridge power pin 42 and a second lower-bridge power pin 42, which are respectively configured to connect to the first lower-bridge power board 321 and the second lower-bridge power board 322. If a power chip needs to be installed on the first lower-bridge power board 321, then two corresponding first lower-bridge power pins 42 are provided to lead the power chip on the first lower-bridge power board 321 outwards for connection to external circuitry.

[0047] As an optional implementation method, such as Figure 2 As shown, the upper bridge power pins 41 are all narrow-body power pins 43 of the same size; the lower bridge power pins 42 consist of narrow-body power pins 43 and wide-body power pins 44 spaced apart. Specifically, the upper bridge power pins 41 are connected to the frame body 1 via longitudinal connecting ribs 22, and all are narrow-body power pins 43. In this embodiment, the size of the upper bridge power pins 41 can be the same as the size of the longitudinal connecting ribs 22, or it can be designed according to the application requirements of the power module on the PCB board.

[0048] Due to the correspondence between the number of power chips and power pins 4, one power chip needs to correspond to two power pins 4. Therefore, the lower bridge power pins 42 corresponding to the lower bridge power board 32 are provided with an even number of power pins 4. One power chip in the lower bridge power module corresponds to one narrow-body power pin 43 and one wide-body power pin 44. Figure 2 As shown, the lower bridge power board 32 includes a first lower bridge power board 321 and a second lower bridge power board 322. Each of the first lower bridge power board 321 and the second lower bridge power board 322 has a power chip. Therefore, there are two narrow-body power pins 43 and two wide-body power pins 44, which are spaced apart. In this embodiment, using wide-body power pins 44 in the lower bridge power pins 42 avoids heat concentration during current connection, which could lead to power module burnout, thus improving the stability and reliability of the power module during operation.

[0049] As an optional implementation, an auxiliary fastening groove 45 is provided on the wide-body power pin 44 in the lower bridge power pin 42. For ease of processing, the depth of the auxiliary fastening groove 45 is the same as the half-etch thickness, and the auxiliary fastening groove 45 is located on the same side as the half-etched area of ​​the power board 3. The auxiliary fastening groove 45 is used to fasten the wide-body power pin 44 to the package body during the power module packaging. It should be noted that setting the auxiliary fastening groove 45 on the same side as the half-etched area of ​​the power board 3 is only for the convenience of frame processing, not a limitation. It can also be located on a different side, depending on the actual application and power requirements.

[0050] Specifically, the upper bridge power pin 41 and the lower bridge power pin 42 are the same, both having two sides. One side is directly connected to the power chip set on the upper bridge power board 31 and the lower bridge power board 32, and the other side is for subsequent packaging to form a power module.

[0051] like Figure 2 As shown, an auxiliary fastening groove 45 is provided on the wide-body power pin 44, and the auxiliary fastening groove 45 is located on the same side as the half-etched area of ​​the power board 3. During the packaging process of the power module, under the action of the auxiliary fastening groove 45, the encapsulation insulating material can fasten the wide-body power pin 44 to the encapsulation material, making it less likely to fall off due to the external environment and improving the adhesion of the encapsulation material. At the same time, the auxiliary fastening groove 45 enables the power module to have high consistency when the power current is combined, and reduces the contact area with the external PCB board when outputting externally, thereby reducing the internal and external stray inductance of the power module during operation, and increasing the stability and safety of the power module.

[0052] It should be noted that the depth of the auxiliary fastening groove 45 is 1 / 4 to 1 / 2 of the thickness of the wide-body power pin 44. Specifically, the depth of the auxiliary fastening groove 45 is defined as D, and the thickness of the wide-body power pin 44 is defined as T. The relationship between the depth D of the auxiliary fastening groove 45 and the thickness T of the wide-body pin is: 0 < D < T, preferably D = 1 / 4 * T to 1 / 2 * T. The groove depth of the auxiliary fastening groove 45 is preferably 1 / 4 of the thickness of the wide-body power pin 44. In this embodiment, the thickness of the wide-body power pin 44 is selected as 0.2 mm, and according to the thinnest wall thickness of the epoxy resin and the creepage clearance requirements, the depth of the auxiliary fastening groove 45 is set to 0.05 mm. The purpose of setting the auxiliary fastening groove 45 and setting the groove depth of the auxiliary fastening groove 45 to 1 / 4 of the thickness of the wide-body power pin 44 is to ensure that the exposed area of ​​the pin can make contact with the PCB and ensure its electrical performance; the non-exposed pin area can act as a blocking insulation layer and meet the withstand voltage index; after encapsulation, the auxiliary fastening groove 45 will be filled with epoxy resin to meet the encapsulation and assembly relationship with the lead frame and meet the EMC function.

[0053] It should also be noted that the process flow of the auxiliary fastening groove 45 is as follows: the wide-body power pin 44 is stamped, then excess copper is laser etched, and then the carbonization layer is cleaned, so that the auxiliary fastening groove 45 can be formed on the wide-body power pin 44.

[0054] As an optional implementation method, such as Figure 2 As shown, the semi-etched area includes a power contact surface 33 and an auxiliary fastening surface 34. The auxiliary fastening surface 34 is located around the power contact surface 33. The power contact surface 33 will not be covered by the encapsulating colloid after encapsulation and is used for DC input and AC output. The auxiliary fastening surface 34 is covered by the encapsulating colloid during encapsulation.

[0055] Specifically, such as Figure 2 As shown, the side of the power board 3 that is a semi-etched area includes a power contact surface 33 and an auxiliary fastening surface 34, with the auxiliary fastening surface 34 located around the power contact surface 33. The specific process of forming the power contact surface 33 and the auxiliary fastening surface 34 on the semi-etched area is as follows: semi-etching is performed outwards along the outer edge of the power contact surface 33, thus forming the auxiliary fastening surface 34 on the semi-etched area, around the power contact surface 33. The auxiliary fastening surface 34 can be considered the semi-etched area, while the power contact surface 33 is the un-etched area. Since the auxiliary fastening surface 34 is the semi-etched area, it is concave inwards compared to the power contact surface 33. Therefore, during encapsulation, the auxiliary fastening surface 34 will be covered by the encapsulating adhesive, further improving the adhesion of the encapsulating adhesive and making it less prone to detachment due to external influences. The power contact surface 33 is the un-etched area, therefore, it will not be covered by the encapsulating adhesive after encapsulation. The power contact surface 33 is used for both DC input and AC output.

[0056] This embodiment reduces the resistance of the power module during power transmission by performing a half-etching design on the other side of the power board 3, thereby improving current transmission efficiency and power module performance.

[0057] It should be noted that the depth of the auxiliary fastening surface 34 formed after the semi-etching is 1 / 4 to 1 / 2 of the thickness of the power board 3. Specifically, the depth of the auxiliary fastening surface 34 is defined as D1, and the thickness of the power board 3 is defined as T1. The relationship between the thickness T1 of the power board 3 and the depth D1 of the auxiliary fastening surface 34 formed by the semi-etching is: 0 < D1 < T1. In this embodiment, the depth D1 of the auxiliary fastening surface 34 is preferably one-quarter T1. In this embodiment, the thickness of the power board 3 is selected as 0.2 mm, and according to the minimum wall thickness of the epoxy resin and the creepage clearance requirements, the depth D1 of the auxiliary fastening surface 34 is set to 0.05 mm.

[0058] The thickness of the power contact surface 33, formed by etching the other half of the power board 3, is consistent with the thickness of the auxiliary fastening groove 45. When encapsulated with encapsulant, the lead frame portion can be encapsulated inside the encapsulant, improving the adhesion of the encapsulant and facilitating its flow, thus improving the consistency of product performance. Simultaneously, while ensuring low resistance, it also possesses strong heat resistance and heat dissipation capabilities, further improving current transmission efficiency and the reliability of the power module.

[0059] As an optional implementation, the lead frame can be made of copper, aluminum, gold, silver, copper alloy, or aluminum alloy. In this embodiment, the overall material of the lead frame (frame body 1, power board 3, and power pins 4) is preferably any one of T2 copper, pure copper, or plate copper, which can reduce costs and increase efficiency.

[0060] It should be noted that the lead frame in this embodiment can be mass-produced, with multiple lead frames manufactured simultaneously and then cut to size. This makes it suitable for industrial production. Mass-produced lead frames include, for example... Figure 3 , Figure 4 As shown.

[0061] The embodiment is merely a special case and does not indicate that this utility model is implemented in such a way.

[0062] Example 2:

[0063] The second embodiment of this utility model also discloses a power module, such as Figure 5 , Figure 6 As shown, the device includes the power module lead frame described in Embodiment 1, as well as a power chip 55, an electrical connector 6, and an encapsulating colloid 7. The power chip 5 is disposed in the power chip placement area on the power board 3. The electrical connector 6 connects the power chip 5 to the power pins 4 to achieve its electrical function. The encapsulating colloid 7 encapsulates the power chip 5, the power pins 4, and the electrical connector 6. Specifically, the power chip 5 is disposed in the power chip placement area of ​​the power board 3 in the lead frame. After placement, the power chip 5 is connected to the power pins 4 through the electrical connector 6. After connection, encapsulation is performed. After encapsulation, the frame body and part of the connecting ribs are cut off to form the power module.

[0064] Electrical connector 6 is made of aluminum wire, copper wire, gold wire, silver wire, aluminum strip, or copper strip. For example... Figure 7 , Figure 8As shown, the power chip 5 can be electrically connected to the power pins 4 in the lead frame via flexible electrical connectors 6, such as metal wires (aluminum wires, copper wires, gold wires, silver wires) or metal strips (copper strips, aluminum strips). Compared to metal wires, metal strips have a larger current-carrying cross-section, which can further improve the problem of insufficient current. At the same time, the current flow direction changes from point to surface contact, thereby improving the impact of parasitic inductance on the bypass magnetic field, resulting in better current-combining effect and stronger stability. In addition, the metal strip also has a heat dissipation effect, further improving the heat dissipation capacity of the power module, with a double-sided heat dissipation effect.

[0065] The power chip 5 used in this solution is a MOSFET, which can be replaced by equivalents such as SiC IGBT, SiC MOSFET, GaN power chip 5, etc., all of which can be used on the power module lead frame.

[0066] In this embodiment, the lead frame uses a MOSFET as the power chip and an H-bridge module structure as an example. The drain (D) of the MOSFET is set in the power chip setting area on the upper bridge power board 3, the power chip setting area on the first lower bridge power board 3, and the power chip setting area on the second lower bridge power board 3 via solder (solder pad, solder wire, solder paste, etc.). Two power MOSFET chips are integrally set in the power chip setting area on the upper bridge power board 3 (or power MOSFET chips can be set separately and corresponding one-to-one with the lower bridge power area). One power MOSFET chip is set in the power chip setting area on the first lower bridge power area and the power chip setting area on the second lower bridge power area. The power chips 5 on the power chip setting areas on the upper bridge power board 3, the first lower bridge power board 3, and the second lower bridge power board 3 can be set according to the specific bridge electrical topology, such as half-bridge, three-phase full-bridge, etc.

[0067] Specifically, the orientation of the MOSFETs in the power chip setting area of ​​the upper bridge power region can be changed according to the actual application of the external PCB board, so that the pin frame described in Embodiment 1 has good compatibility.

[0068] The encapsulating colloid 7 is an insulating colloid such as epoxy resin or silicone gel. No specific limitation is made in this embodiment.

[0069] It should be noted that, since the lead frame in Embodiment 1 can be mass-produced, power chips 5 and electrical connectors 6 can also be mounted on the mass-produced lead frame and encapsulated using encapsulating colloid 7. Multiple power modules can be fabricated simultaneously, and subsequently cut to form multiple individual power modules. The mass-produced power modules are as follows: Figure 9 As shown.

[0070] The above description is merely a preferred embodiment of the present utility model. Those skilled in the art will understand that various changes or equivalent substitutions can be made to these features and embodiments without departing from the spirit and scope of the present utility model. Furthermore, under the teachings of the present utility model, these features and embodiments can be modified to adapt to specific situations and materials without departing from the spirit and scope of the present utility model. Therefore, the present utility model is not limited to the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this application are within the protection scope of the present utility model.

Claims

1. A power module lead frame, characterized in that, It includes a frame body (1), connecting ribs (2), multiple power boards (3) and multiple power pins (4). The multiple power boards (3) and the multiple power pins (4) are all set in the frame body (1) through the connecting ribs (2). The power pins (4) are set in correspondence with the power boards (3). One side of the power board (3) is a power chip mounting area for mounting power chips, and the other side is a semi-etched area for power input and power output. The plurality of power pins (4) are used to connect the power chip located on the power chip setting area to an external circuit.

2. The power module lead frame according to claim 1, characterized in that, The semi-etched area includes a power contact surface (33) and an auxiliary fastening surface (34), the auxiliary fastening surface (34) being located around the power contact surface (33); the power contact surface (33) is not covered by the encapsulating colloid during encapsulation and is used for DC input and AC output; the auxiliary fastening surface (34) is covered by the encapsulating colloid during encapsulation.

3. The power module lead frame according to claim 2, characterized in that, The etching depth of the auxiliary fastening surface (34) is 1 / 4 to 1 / 2 of the thickness of the power board (3).

4. The power module lead frame according to claim 1, characterized in that, The power plate (3) includes an upper bridge power plate (31) and a lower bridge power plate (32), and the upper bridge power plate (31) and the lower bridge power plate (32) are laterally connected to the frame body (1) through transverse connecting ribs (21); The power pin (4) includes multiple upper bridge power pins (41) and multiple lower bridge power pins (42). The upper bridge power pins (41) and lower bridge power pins (42) extend inward from the edge of the frame body (1) through longitudinal connecting ribs (22). The upper bridge power pins (41) and lower bridge power pins (42) are located on the sides of the upper bridge power plate (31) and the lower bridge power plate (32), respectively.

5. The power module lead frame according to claim 4, characterized in that, The upper bridge power pins (41) are all narrow-body power pins (43) of the same size; the lower bridge power pins (42) are narrow-body power pins (43) and wide-body power pins (44) spaced apart.

6. The power module lead frame according to claim 5, characterized in that, An auxiliary fastening groove (45) is provided on the wide-body power pin (44). The auxiliary fastening groove (45) is located on the same side as the half-etched area of ​​the power board (3). The auxiliary fastening groove (45) is used to fasten the wide-body power pin (44) to the encapsulation colloid when the power module is packaged.

7. The power module lead frame according to claim 6, characterized in that, The depth of the auxiliary fastening groove (45) is 1 / 4 to 1 / 2 of the thickness of the wide-body power pin (44).

8. The power module lead frame according to any one of claims 1-7, characterized in that, The ratio of the number of power chips to the number of power pins (4) is 1:

2.

9. A power module, characterized in that, The power module lead frame according to any one of claims 1-8 further includes a power chip (5), an electrical connector (6), and an encapsulating colloid (7); the power chip (5) is disposed in the power chip placement area on the power board (3), the electrical connector (6) connects the power chip (5) to the power pin (4) to realize its electrical function; the encapsulating colloid (7) is used to encapsulate the power chip (5), the power pin (4), and the electrical connector (6).

10. The power module according to claim 9, characterized in that, The electrical connector (6) is an aluminum wire, copper wire, gold wire, silver wire, aluminum strip, or copper strip; the power chip (5) is a MOSFET; and the encapsulating colloid (7) is epoxy resin or silicone gel.

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