TO247 packaging structure suitable for double-sided heat dissipation

Abstract

The TO247 packaging structure comprises a heat dissipation top plate, a chip, a heat dissipation bottom plate and a plastic package body, the chip is arranged on the lower surface of the heat dissipation top plate, the heat dissipation bottom plate is electrically connected to the lower surface of the chip, and the plastic package body wraps the heat dissipation top plate, the chip and the heat dissipation bottom plate. The heat dissipation top plate is provided with a first heat dissipation surface exposed out of the upper surface of the plastic package body, the first heat dissipation surface can be used for installing a radiator, the heat dissipation bottom plate is provided with a second heat dissipation surface exposed out of the lower surface of the plastic package body, the second heat dissipation surface is flush with the lower surface of the plastic package body, and one side of the heat dissipation top plate is provided with a pin extending out of the plastic package body. One end, far away from the plastic package body, of each pin is provided with a bending part which is bent downwards, the lower end of each bending part is not higher than the second heat dissipation surface, and both the second heat dissipation surface and the bending parts can be welded with the circuit board. According to the utility model, a double-sided heat dissipation structure is adopted, and the flat-lying surface mounting on the circuit board is realized, so that the occupied space above the circuit board is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of chip packaging, in particular to a TO247 packaging structure suitable for double-sided heat dissipation. Background Art

[0002] The TO247 package is a reliable, stable and efficient electronic component package, which is widely used in various high-power electronic devices. The traditional TO247 package structure mainly includes a heat sink, a chip and a plastic package. The chip is attached to the front of the heat sink, and the plastic package is exposed on the back of the heat sink. The lower end of the heat sink is provided with pins extending vertically downward. During assembly, the pins are inserted downward into the welding holes on the circuit board, and the welding material is filled into the welding holes to weld the pins to the circuit board. However, since the TO247 package structure is welded on the circuit board in an inverted manner, it will occupy a large space above the circuit board. Utility Model Content

[0003] The utility model aims at the defects of the prior art and provides a TO247 packaging structure suitable for double-sided heat dissipation. The TO247 packaging structure adopts a double-sided heat dissipation structure and is mounted on a circuit board in a flat manner, thereby reducing the space occupied above the circuit board.

[0004] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0005] A TO247 packaging structure suitable for double-sided heat dissipation comprises a heat dissipation top plate, a chip, a heat dissipation bottom plate and a plastic package body, wherein the chip is arranged on the lower surface of the heat dissipation top plate, the heat dissipation bottom plate is electrically connected to the lower surface of the chip, the plastic package body covers the heat dissipation top plate, the chip and the heat dissipation bottom plate, the heat dissipation top plate has a first heat dissipation surface exposed on the upper surface of the plastic package body, the first heat dissipation surface can be used to install a radiator, the heat dissipation bottom plate has a second heat dissipation surface exposed on the lower surface of the plastic package body, the second heat dissipation surface is flush with the lower surface of the plastic package body, one side of the heat dissipation top plate is provided with a pin extending out of the plastic package body, the end of the pin away from the plastic package body is provided with a bending portion bent downward, the lower end of the bending portion is not higher than the second heat dissipation surface, and both the second heat dissipation surface and the bending portion can be welded to a circuit board.

[0006] By arranging a first heat dissipation surface on the heat dissipation top plate, electrically connecting the heat dissipation bottom plate on the lower surface of the chip, and arranging a second heat dissipation surface on the heat dissipation bottom plate, the second heat dissipation surface is flush with the lower surface of the plastic package body, and a double-sided heat dissipation structure is adopted, so that the heat dissipation effect is better; at the same time, a pin extending out of the plastic package body is arranged on one side of the heat dissipation top plate, and a bent portion bent downward is arranged at one end of the pin away from the plastic package body, and the lower end of the bent portion is not higher than the second heat dissipation surface. During assembly, the second heat dissipation surface and the bent portion are welded to the circuit board, so that the TO247 packaging structure can be mounted on the circuit board in a lying manner, thereby reducing the space occupied above the circuit board; in addition, the bent portion can also absorb the thermal expansion deformation of the entire structure, thereby improving the reliability of the device after assembly, and the welding of the second heat dissipation surface and the circuit board can realize direct conduction between the chip current and the circuit board, thereby reducing the loss caused by the conduction of the pins, and can also introduce the heat generated by the chip into the circuit board, thereby facilitating heat diffusion and improving the heat dissipation effect.

[0007] As a preferred embodiment, the bending portion includes a first bending section and a second bending section, the upper end of the first bending section is integrally connected to the pin, the lower end of the first bending section is integrally connected to the second bending section, the second bending section extends horizontally away from the plastic package body, and the lower surface of the second bending section is flush with the second heat dissipation surface. During assembly, the second bending section is welded to the circuit board.

[0008] As a preferred solution, the bending portion is a vertical section extending downward perpendicular to the pin, and the lower end of the vertical section is lower than the second heat dissipation surface. During assembly, the vertical section is passed through a welding hole on the circuit board, and the vertical section is welded to the circuit board.

[0009] Compared with the prior art, the utility model has obvious advantages and beneficial effects. Specifically, a first heat dissipation surface is arranged on the heat dissipation top plate, the lower surface of the chip is electrically connected to the heat dissipation bottom plate, and a second heat dissipation surface is arranged on the heat dissipation bottom plate. The second heat dissipation surface is flush with the lower surface of the plastic package body, and a double-sided heat dissipation structure is adopted, so that the heat dissipation effect is better; at the same time, a pin extending out of the plastic package body is arranged on one side of the heat dissipation top plate, and a bent portion bent downward is arranged at one end of the pin away from the plastic package body, and the lower end of the bent portion is not higher than the second heat dissipation surface. During assembly, the second heat dissipation surface and the bent portion are welded to the circuit board, so that the TO247 packaging structure can be mounted on the circuit board in a lying manner, thereby reducing the space occupied above the circuit board; in addition, the bent portion can also absorb the thermal expansion deformation of the entire structure, thereby improving the reliability of the device after assembly. The welding of the second heat dissipation surface and the circuit board can realize direct conduction between the chip current and the circuit board, thereby reducing the loss caused by the conduction of the pins, and can also introduce the heat generated by the chip into the circuit board, thereby facilitating heat diffusion and improving the heat dissipation effect.

[0010] In order to more clearly illustrate the structural features, technical means and specific purposes and functions achieved by the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments: BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 It is a schematic cross-sectional view of a TO247 package structure suitable for double-sided heat dissipation according to the first embodiment of the utility model;

[0012] Figure 2 It is a cross-sectional schematic diagram of a TO247 package structure suitable for double-sided heat dissipation, a heat sink, and a circuit board assembly according to the first embodiment of the utility model;

[0013] Figure 3 It is a schematic cross-sectional view of a TO247 package structure suitable for double-sided heat dissipation according to the second embodiment of the utility model;

[0014] Figure 4 It is a cross-sectional schematic diagram of a TO247 package structure suitable for double-sided heat dissipation, a heat sink, and a circuit board assembly according to the second embodiment of the utility model.

[0015] Description of the accompanying drawings:

[0016] 10-heat dissipation top plate; 101-first heat dissipation surface; 11-chip; 12-heat dissipation bottom plate; 121-second heat dissipation surface 13-plastic package; 14-pin; 15-bending portion; 151-first bending section; 152-second bending section; 153-vertical section; 20-heat sink; 30-circuit board; 31-welding hole. DETAILED DESCRIPTION

[0017] In the description of the present invention, it should be noted that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc. indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the utility model and simplifying the description, and do not indicate or imply that the position or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they cannot be understood as limitations on the present invention.

[0018] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0019] like Figure 1-2As shown, the utility model discloses a TO247 packaging structure suitable for double-sided heat dissipation. In the first embodiment, it includes a heat dissipation top plate 10, a chip 11, a heat dissipation bottom plate 12 and a plastic package 13. The chip 11 is arranged on the lower surface of the heat dissipation top plate 10, the heat dissipation bottom plate 12 is electrically connected to the lower surface of the chip 11, and the plastic package 13 covers the heat dissipation top plate 10, the chip 11 and the heat dissipation bottom plate 12. The heat dissipation top plate 10 has a first heat dissipation surface 101 exposed on the upper surface of the plastic package 13. The first heat dissipation surface 101 can be used to install a radiator. 20, the first heat dissipation surface 101 is flush with the upper surface of the plastic package 13, the heat dissipation bottom plate 12 has a second heat dissipation surface 121 exposed from the lower surface of the plastic package 13, the second heat dissipation surface 121 is flush with the lower surface of the plastic package 13, one side of the heat dissipation top plate 10 is provided with a pin 14 extending out of the plastic package 13, the end of the pin 14 away from the plastic package 13 is provided with a bending portion 15 bent downward, the lower end of the bending portion 15 is not higher than the second heat dissipation surface 121, and the second heat dissipation surface 121 and the bending portion 15 can both be welded to the circuit board 30.

[0020] Specifically, the bending portion 15 includes a first bending section 151 and a second bending section 152, the upper end of the first bending section 151 is integrally connected to the pin 14, the lower end of the first bending section 151 is integrally connected to the second bending section 152, the second bending section 152 extends horizontally away from the plastic package body 13, and the lower surface of the second bending section 152 is flush with the second heat dissipation surface 121. During assembly, the second bending section 152 is welded to the circuit board 30; by setting the bending portion 15 composed of the first bending section 151 and the second bending section 152, the lower surface of the second bending section 152 is flush with the second heat dissipation surface 121, thereby indirectly reducing the height of the pin 141, so that the second bending section 152 and the second heat dissipation surface 121 can be welded to the same side surface of the circuit board 30, thereby realizing that the TO247 packaging structure is flatly mounted on the circuit board 30.

[0021] like Figure 3-4 As shown, in the second embodiment, the difference from the first embodiment is that the bending portion 15 is a vertical section 153 extending downwardly perpendicular to the pin 14, and the lower end of the vertical section 153 is lower than the second heat dissipation surface 121. During assembly, the vertical section 153 is inserted into the welding hole 31 on the circuit board 30, and the vertical section 153 is welded to the circuit board 30. Specifically, during welding, the welding hole 31 is filled with solder material to weld the vertical section 153 to the circuit board 30.

[0022] In summary, the utility model provides a first heat dissipation surface 101 on the heat dissipation top plate 10, electrically connects the lower surface of the chip 11 to the heat dissipation bottom plate 12, and provides a second heat dissipation surface 121 on the heat dissipation bottom plate 12. The second heat dissipation surface 121 is flush with the lower surface of the plastic package 13, and a double-sided heat dissipation structure is adopted to achieve a better heat dissipation effect. At the same time, a pin 14 extending out of the plastic package 13 is provided on one side of the heat dissipation top plate 10, and a bent portion 15 bent downward is provided at one end of the pin 14 away from the plastic package 13, and the lower end of the bent portion 15 is not higher than the second heat dissipation surface 121. When assembling, By welding the second heat dissipation surface 121 and the bending portion 15 to the circuit board 30, the TO247 package structure can be mounted on the circuit board 30 in a lying manner, reducing the space occupied above the circuit board 30; in addition, the bending portion 15 can also absorb the thermal expansion deformation of the entire structure, thereby improving the reliability of the device after assembly. The welding of the second heat dissipation surface 121 and the circuit board 30 can realize direct conduction between the chip 11 current and the circuit board 30, thereby reducing the loss caused by the conduction of the pin 14, and can also conduct the heat generated by the chip 11 to the circuit board 30, thereby facilitating heat diffusion and improving the heat dissipation effect.

[0023] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Therefore, any modification, equivalent replacement, improvement, etc. made to the above embodiment based on the technical practice of the present invention still falls within the scope of the technical solution of the present invention.

Claims

1. A TO247 package structure suitable for double-sided heat dissipation, characterized in that: It includes a heat dissipation top plate, a chip, a heat dissipation bottom plate and a plastic package body, wherein the chip is arranged on the lower surface of the heat dissipation top plate, the heat dissipation bottom plate is electrically connected to the lower surface of the chip, the plastic package body covers the heat dissipation top plate, the chip and the heat dissipation bottom plate, the heat dissipation top plate has a first heat dissipation surface exposed on the upper surface of the plastic package body, the first heat dissipation surface can be used to install a radiator, the heat dissipation bottom plate has a second heat dissipation surface exposed on the lower surface of the plastic package body, the second heat dissipation surface is flush with the lower surface of the plastic package body, one side of the heat dissipation top plate is provided with a pin extending out of the plastic package body, the end of the pin away from the plastic package body is provided with a bending portion bent downward, the lower end of the bending portion is not higher than the second heat dissipation surface, and the second heat dissipation surface and the bending portion can be welded to the circuit board.

2. The TO247 package structure suitable for double-sided heat dissipation according to claim 1, characterized in that: The bending portion includes a first bending section and a second bending section, the upper end of the first bending section is integrally connected to the pin, the lower end of the first bending section is integrally connected to the second bending section, the second bending section extends horizontally away from the plastic package body, and the lower surface of the second bending section is flush with the second heat dissipation surface. During assembly, the second bending section is welded to the circuit board.

3. The TO247 package structure suitable for double-sided heat dissipation according to claim 1, characterized in that: The bending portion is a vertical section extending downward perpendicular to the pin, the lower end of the vertical section is lower than the second heat dissipation surface, and during assembly, the vertical section is inserted into a welding hole on the circuit board, and the vertical section is welded to the circuit board.

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