Power module

Abstract

The utility model provides a power module, which comprises a plastic package body and a plurality of pins, the plastic package body is provided with a top surface and a bottom surface which are oppositely arranged and two side surfaces which are oppositely arranged, the pins are led out from the side surfaces of the plastic package body, a groove is arranged between at least one group of two adjacent pins, and the grooves are communicated with the top surface and the bottom surface of the plastic package body. The groove does not penetrate through the top surface and / or the bottom surface; under the condition that the overall size of the power module is not changed and the creepage distance and the bending strength are not reduced, the stress concentration at the groove is avoided, and further the power module is prevented from being broken from the groove in the process of locking a fastener on a production line of a workshop.

Description

Technical Field

[0001] The utility model relates to the technical field of semiconductors, in particular to a power module. Background Art

[0002] With the continuous improvement of the process integration of electronic devices, electronic equipment has become smaller and smaller, which requires the manufacture of power modules with smaller sizes. However, power modules with smaller sizes will limit the creepage distance between adjacent pins. Especially for high-voltage power modules, in actual applications, when a high voltage is applied to the pins of the power module, leakage may occur on the surface of the plastic package between two adjacent pins due to insufficient creepage distance, thus reducing the insulation strength of the power module. On the contrary, if the creepage distance between two adjacent pins meets the insulation safety standard, the size of the high-voltage power module chip cannot be further reduced. Therefore, there is an irreconcilable contradiction between the creepage distance and the size of the power module.

[0003] To increase the creepage distance, grooves are usually provided that longitudinally penetrate the top and bottom surfaces of the plastic package. However, to improve the heat dissipation capacity, some power modules need to install heat dissipation fins, which are specifically locked on the top surface of the plastic package by fasteners passing through the plastic package from the bottom surface. Since the top surface of the plastic package and the heat dissipation fin are not perfect planes and have uneven undulations, it is required that the plastic package has a certain flexural strength to prevent the chip from breaking after the fastener is locked. However, the groove is a stress concentration point of the plastic package. Due to the existence of this groove, the power module is prone to break from the groove during the process of locking the fastener on the production line in the workshop. Summary of the Utility Model

[0004] The purpose of the utility model is to provide a power module to solve the problem that the existing power module is prone to break from the groove.

[0005] To achieve the above purpose, the utility model provides a power module, including a plastic package and a plurality of pins. The plastic package has a top surface and a bottom surface arranged oppositely and two side surfaces arranged oppositely, and the pins are led out from the side surfaces of the plastic package; and,

[0006] There is at least one groove between at least a group of adjacent two pins, and the groove does not penetrate the top surface and / or the bottom surface.

[0007] Optionally, the side surface has a protruding edge parallel to the top surface and the bottom surface, and the groove is at least one of the following situations:

[0008] The groove extends from the top surface to the region between the edge and the bottom surface, from the bottom surface to the region between the edge and the top surface, and from the region between the top surface and the edge to the region between the bottom surface and the edge.

[0009] Optionally, the groove is located between two adjacent pins having a potential difference.

[0010] Optionally, the groove is provided between two adjacent pins with a potential difference greater than 125V.

[0011] Optionally, after the pins are led out from the side surface of the plastic package, they extend in the direction from the top surface to the bottom surface.

[0012] Optionally, the pins are surface mount pins.

[0013] Optionally, in the arrangement direction of the pins, the width of the notch of the groove is greater than the width of the groove bottom, the notch is the open end of the groove, and the groove bottom is the closed end of the groove.

[0014] Optionally, between two adjacent pins having the groove, the creepage distance between the two adjacent pins is increased through the groove, so that the creepage distance along the edge of the groove is greater than or equal to the creepage distance along the inner surface of the groove.

[0015] Optionally, the top surface is a flat surface.

[0016] Optionally, the edge of the top surface has a step, and the top surface is connected to the side surface through the step.

[0017] Optionally, the plastic package further includes a fastening hole, and a heat dissipation member is fastened to the power module through the fastening hole.

[0018] In the power module provided by the present utility model, it includes a plastic package and a plurality of pins. The plastic package has a top surface and a bottom surface arranged oppositely and two side surfaces arranged oppositely. The pins are led out from the side surfaces of the plastic package, and the pins can be through-hole pins or surface mount pins. There is at least one set of grooves between two adjacent pins, the grooves do not penetrate the top surface and / or the bottom surface, and there is a potential difference between two adjacent pins having the grooves. The present utility model can avoid stress concentration at the grooves without changing the overall size of the power module, and without reducing the creepage distance and bending strength, thereby avoiding the power module from breaking at the grooves during the process of locking the fasteners on the production line in the workshop. Description of the Drawings

[0019] Figures 1 to 4Schematic diagrams of the power module provided in the first embodiment of the present utility model from four different perspectives;

[0020] Figure 5 Partial structural schematic diagram of the power module provided in the first embodiment of the present utility model;

[0021] Figures 6 to 9 Schematic diagrams of the power module provided in the second embodiment of the present utility model from four different perspectives;

[0022] Figures 10 to 12 Schematic diagrams of the power module provided in the third embodiment of the present utility model from three different perspectives;

[0023] Figures 13 to 15 Schematic diagrams of the power module provided in the fourth embodiment of the present utility model from three different perspectives;

[0024] Among them, the reference numerals are:

[0025] 100 - plastic package; 100a - top surface; 100b - bottom surface; 100c - side surface; 200, a, b, c, d, e - pins; 300 - groove; 400 - step; x - x direction; y - y direction; z - z direction. Detailed implementation manners

[0026] The following will describe the detailed implementation manners of the present utility model in more detail with reference to the schematic diagrams. According to the following description, the advantages and features of the present utility model will be clearer. It should be noted that the drawings are all in a very simplified form and use non - precise scales, only for the purpose of facilitating and clearly assisting in explaining the purpose of the embodiments of the present utility model.

[0027] Embodiment 1

[0028] Figures 1 to 4 Schematic diagrams of the power module provided in this embodiment from four different perspectives. As Figures 1 to 4 shown, the power module includes a plastic package 100 and a plurality of pins 200.

[0029] Specifically, the plastic package 100 has a top surface 100a and a bottom surface 100b that are oppositely arranged and two side surfaces 100c that are oppositely arranged. The top surface 100a is the heat - dissipation surface of the power module. In some embodiments, a heat - dissipation component can be installed on the top surface 100a. The heat - dissipation component can be a heat - dissipation fin. Specifically, the plastic package 100 further includes fastening holes. The heat - dissipation fin is fastened to the top surface 100a by a fastener passing through the fastening holes of the plastic package 100. The side surface 100c is used to lead out the pins 200.

[0030] The pin 200 is led out from the side surface 100c of the plastic package 100. Specifically, the power module can be a through-hole package, and the pin is a through-hole pin. After the pin 200 is led out from the side surface 100c of the plastic package 100, it extends along the direction (y direction) from the top surface 100a to the bottom surface 100b. On each side surface 100c, a plurality of the pins 200 are arranged in a straight line along the x direction, and there is a spacing between two adjacent pins 200.

[0031] In some embodiments, the power module can be a surface-mount package, and the pin is a surface-mount pin. At this time, after the pin 200 is led out from the side surface 100c of the plastic package 100, it can extend along the direction (z direction) perpendicular to the side surface 100c.

[0032] It should be understood that the plastic package 100 is not limited to having only two side surfaces 100c for setting the pins 200. In some embodiments, the plastic package 100 can also have 4 side surfaces 100c for setting the pins 200, and the 4 side surfaces 100c are arranged in pairs opposite to each other, thereby increasing the design flexibility.

[0033] When the power module works, there may be a potential difference between two adjacent pins 200 with unequal electric potentials on each side surface 100c. For example, as Figure 1 shown, on the side surface 100c, there are pins a, b, c, d, e... arranged in sequence along the x direction. The pin a is adjacent to the pin b. If the electric potentials on the pin a and the pin b are unequal when the power module works, then the pin a and the pin b are two adjacent pins 200 with a potential difference; the pin b is adjacent to the pin c. If the electric potentials on the pin b and the pin c are unequal when the power module works, then the pin b and the pin c are two adjacent pins 200 with a potential difference; the pin c is adjacent to the pin d. If the electric potentials on the pin c and the pin d are unequal when the power module works, then the pin c and the pin d are two adjacent pins 200 with a potential difference; the pin d is adjacent to the pin e. If the electric potentials on the pin d and the pin e are unequal when the power module works, then the pin d and the pin e are two adjacent pins 200 with a potential difference...

[0034] In this embodiment, the pin b and the pin c, and the pin d and the pin e are two adjacent pins 200 with a potential difference.

[0035] In this embodiment, there is a groove 300 between at least one group of adjacent two of the pins 200, and the groove 300 does not penetrate the top surface 100a and / or the bottom surface 100b. It should be noted that the side surface has a protruding edge parallel to the top surface and the bottom surface. The groove 300 may be at least one of the following cases: the groove 300 extends from the top surface 100a to the area between the edge and the bottom surface 100b, the groove 300 extends from the bottom surface 100b to the area between the edge and the top surface 100a, and the groove 300 extends from the area between the top surface 100a and the edge to the area between the bottom surface 100b and the edge.

[0036] Furthermore, in this embodiment, the groove 300 is located between adjacent two of the pins 200 having a potential difference. Specifically, there is the groove 300 between the pin b and the pin c and between the pin d and the pin e. The groove 300 extends from the side surface 100c into the plastic package 100, and the groove 300 penetrates the top surface 100a until it exceeds the pin 200, but does not penetrate the bottom surface 100b. In other words, the side surface 100c has an edge parallel to the arrangement direction of the pins 200, and the groove 300 extends from the top surface 100a along the y direction to the area between the edge and the bottom surface 100b. In this way, without changing the overall size of the power module, and without reducing the creepage distance and bending strength, stress concentration at the groove 300 can be avoided, and thus the power module can be prevented from breaking at the groove 300 during the process of tightening the fasteners on the production line in the workshop.

[0037] It should be noted that, on the basis that both the creepage distance and the size of the power module meet the requirements, the groove 300 may be provided between at least one group of adjacent two of the pins 200 having a potential difference, or may be provided between all adjacent two of the pins 200 having a potential difference.

[0038] It can be understood that the greater the potential difference between adjacent two of the pins 200, the higher the requirement for the creepage distance between adjacent two of the pins 200. Therefore, the groove 300 may be provided between adjacent two of the pins 200 with a potential difference greater than 125V, but this should not be taken as a limitation.

[0039] Further, in this embodiment, along the arrangement direction (x-direction) of the pin 200, the width of the notch of the groove 300 is greater than the width of the bottom of the groove. The notch is the open end of the groove 300, and the bottom of the groove is the closed end of the groove 300, so that the groove 300 has a structure with a large opening and a small bottom. In this way, when encapsulating the power module, the plastic package 100 is easier to demold. In some embodiments, along the arrangement direction (x-direction) of the pin 200, the width of the notch of the groove 300 may also be equal to the width of the bottom of the groove, and the present invention does not limit this.

[0040] Figure 5 is a partial structural schematic diagram of the power module provided in this embodiment. As Figure 5 shown, between two adjacent pins 200 having the groove 300, the creepage distance between the two adjacent pins 200 is increased through the groove 300. The creepage distance L2 along the edge of the groove 300 is greater than the creepage distance L1 along the inner surface of the groove 300, but this is not limited thereto. The creepage distance L2 along the edge of the groove 300 may also be equal to the creepage distance L1 along the inner surface of the groove 300. In this way, on the basis of ensuring that the overall size of the power module remains unchanged (the distance between two adjacent pins 200 remains unchanged), the creepage distance will not decrease.

[0041] Please continue to refer to Figure 1 、 Figure 3 or Figure 4 , in this embodiment, the edge of the top surface 100a has a step 400, and the top surface 100a is connected to the side surface 100c through the step 400. The step 400 can increase the creepage distance between the pin 200 and the top surface 100a.

[0042] Further, the power module may be a power chip or other chips, and the present invention does not limit this.

[0043] Embodiment Two

[0044] Figures 6 to 9 is a structural schematic diagram of the power module provided in this embodiment from 4 different perspectives. As Figures 6 to 9As shown, the difference from the first embodiment is that in this embodiment, the groove 300 does not penetrate the top surface 100a nor the bottom surface 100b. In other words, the groove 300 extends in the y direction from the area between the top surface 100a and the edge to the area between the bottom surface 100b and the edge, and the whole groove 300 is located in the area between the top surface 100a and the bottom surface 100b. In this way, without changing the overall size of the power module, and without reducing the creepage distance and bending strength, the possibility of the power module breaking at the groove 300 during the process of locking the fasteners on the production line in the workshop can be further reduced.

[0045] Further, in this embodiment, the top surface 100a is a flat surface, which is convenient for installing heat dissipation fins, increasing the heat dissipation area, and improving the heat dissipation capacity.

[0046] Embodiment Three

[0047] Figures 10 to 12 are schematic structural diagrams of the power module provided in this embodiment from three different perspectives. As Figures 10 to 12 shown, the difference from the first embodiment is that in this embodiment, the groove 300 does not penetrate the top surface 100a but penetrates the bottom surface 100b. In other words, the groove 300 extends in the y direction from the bottom surface 100b to the area between the top surface 100a and the edge. In this way, without changing the overall size of the power module, and without reducing the creepage distance and bending strength, the possibility of the power module breaking at the groove 300 during the process of locking the fasteners on the production line in the workshop can be further reduced.

[0048] Further, in this embodiment, the top surface 100a is a flat surface, which is convenient for installing heat dissipation fins, increasing the heat dissipation area, and improving the heat dissipation capacity.

[0049] Embodiment Four

[0050] Figures 13 to 15 are schematic structural diagrams of the power module provided in this embodiment from three different perspectives. As Figures 13 to 15 shown, the difference from the first embodiment is that in this embodiment, the pin a and the pin b, the pin b and the pin c, and the pin c and the pin d are all adjacent two pins 200 with a potential difference.

[0051] Further, in this embodiment, there are grooves 300 between the pin a and the pin b, between the pin b and the pin c, and between the pin c and the pin d.

[0052] In summary, in the power module provided by the embodiment of the present utility model, it includes a plastic package body and a plurality of pins. The plastic package body has a top surface and a bottom surface which are oppositely arranged, and two side surfaces which are oppositely arranged. The pins are led out from the side surfaces of the plastic package body. The pins can be through-hole pins or surface-mount pins. There is a groove between at least a group of two adjacent pins. The groove does not penetrate the top surface and / or the bottom surface. There is an electric potential difference between two adjacent pins with grooves. The present utility model can avoid stress concentration at the groove while ensuring that the overall size of the power module remains unchanged, the creepage distance and the bending strength do not decrease, thereby avoiding the power module from breaking at the groove during the process of locking the fasteners on the production line in the workshop.

[0053] It should be noted that the various embodiments in this specification are described in a progressive manner. Each embodiment focuses on the differences from other embodiments. The same or similar parts among the various embodiments can be referred to each other. For the system disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the description of the method part.

[0054] It should also be noted that although the present utility model has been disclosed above with preferred embodiments, the above embodiments are not intended to limit the present utility model. For any person skilled in the art, without departing from the scope of the technical solution of the present utility model, many possible changes and modifications can be made to the technical solution of the present utility model by using the technical content disclosed above, or it can be modified into an equivalent embodiment with equivalent changes. Therefore, any simple modification, equivalent change and modification made to the above embodiments based on the technical essence of the present utility model without departing from the content of the technical solution of the present utility model still belong to the scope of protection of the technical solution of the present utility model.

[0055] It should also be understood that unless otherwise specified or indicated, the terms "first", "second", "third", etc. in the specification are only used to distinguish the various components, elements, steps, etc. in the specification, rather than to represent the logical relationship or sequential relationship between the various components, elements, steps, etc.

[0056] It should also be recognized that the terms described herein are only used to describe specific embodiments and are not intended to limit the scope of the present utility model. It must be noted that the singular forms "a" and "an" used herein and in the appended claims include plural referents unless the context clearly dictates otherwise. For example, a reference to "a step" or "a device" means a reference to one or more steps or devices and may include sub-steps as well as sub-devices. All conjunctions used should be understood in their broadest sense. Also, the word "or" should be understood to have the definition of a logical "or" rather than a logical "exclusive or" unless the context clearly dictates otherwise. In addition, the implementation of the methods and / or devices in the embodiments of the present utility model may include performing the selected tasks manually, automatically, or in combination.

Claims

1. A power module, characterized in that: It comprises a plastic package body and a plurality of pins, wherein the plastic package body has a top surface and a bottom surface which are arranged oppositely and two side surfaces which are arranged oppositely, and the pins are led out from the side surfaces of the plastic package body; as well as, A groove is provided between at least two adjacent pins of a group, and the groove does not penetrate through the top surface and / or the bottom surface.

2. The power module according to claim 1, characterized in that: The side surface has a protruding edge, the edge is parallel to the top surface and the bottom surface, and the groove is at least one of the following conditions: The groove extends from the top surface to the area between the edge and the bottom surface; The groove extends from the bottom surface to the area between the edge and the top surface; The groove extends from the top surface to the area between the edges to the area between the bottom surface and the edges.

3. The power module according to claim 1 or 2, characterized in that: The groove is located between two adjacent pins having a potential difference.

4. The power module according to claim 3, characterized in that: The groove is arranged between two adjacent pins whose potential difference is greater than 125V.

5. The power module according to claim 1 or 2, characterized in that: The pins are led out from the side surfaces of the plastic package body and extend along the direction from the top surface to the bottom surface.

6. The power module according to claim 1 or 2, characterized in that: The pins are surface mount pins.

7. The power module according to claim 1 or 2, characterized in that: In the arrangement direction of the pins, the width of the notch of the groove is greater than the width of the groove bottom, the notch is the open end of the groove, and the groove bottom is the closed end of the groove.

8. The power module according to claim 1 or 2, characterized in that: Between two adjacent pins having the groove, the creepage distance between the two adjacent pins is increased by the groove, so that the creepage distance along the edge of the groove is greater than or equal to the creepage distance along the inner surface of the groove.

9. The power module according to claim 1 or 2, characterized in that: The top surface is a flat surface.

10. The power module according to claim 1 or 2, characterized in that: An edge of the top surface has a step, and the top surface is connected to the side surface via the step.

11. The power module according to claim 1 or 2, characterized in that: The plastic package body also includes a fastening hole, through which a heat sink is fastened to the power module.

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