CN207519067U - Power module - Google Patents

Abstract

The present application provides a new type of power module, which at least includes: a metal casing, and a PCB board arranged in the metal casing; wherein, the PCB board is at least provided with a power switch tube, a first screw hole, a second screw hole, and Gold finger connector located next to the second screw hole; the first screw hole is pierced with a grounding screw connected to the metal casing; the ground noise generated by the power switch tube passes through the first screw hole Afterwards, it will pass through the metal shell to the second screw hole, and then be sent to the outside of the power module through the golden finger connector. In this application, the metal shell is used as the power ground, which reduces the number of layers of the PCB board and saves the cost of the PCB board; in addition, by isolating the power ground and the signal ground, the switching noise will not affect the signal control circuit; the high frequency in the switching noise The switching harmonics will be greatly attenuated on the metal casing, and the conduction interference will not affect the surrounding electronic equipment.

Description

power module

technical field

This application relates to the field of power modules, in particular to a new type of power module.

Background technique

In the design of the power module, due to the existence of the power switch, high di/dt and high du/dt are generated during its rapid turn-on and turn-off process, and the surge current and peak voltage generated by them form a source of noise and interference. In order to prevent it from causing interference to nearby electronic equipment, a metal casing is generally added to suppress its external radiation interference, and external interference is also blocked by the metal casing. Of course, the metal casing here needs to be connected to the ground of the power module to provide protection. effect. However, the rapid turn-on and turn-off of the power switch will also cause conduction interference. In addition to adding filter circuits, the suppression of conduction interference has a lot to do with PCB layout.

In order to suppress the conduction interference, and the noise generated by the power switch will also affect some small signal control circuits of the power module itself, so generally in PCB design, the ground is divided into power ground and signal ground, and they are connected at a single point , so that the switch interference will not have a great impact on the signal control circuit. In PCB design, a complete layer of ground is generally reserved for power ground, and there are certain requirements for the area and thickness of this layer of power ground, so that the high-frequency harmonics in the switching noise are attenuated on the ground plane. As a result, the PCB board will be a multi-layer board design, and the area of the PCB also needs to be increased, and sometimes the copper thickness of the ground layer also needs to be increased, so that the cost of the PCB board will increase significantly.

application content

In view of the shortcomings of the prior art described above, the purpose of this application is to provide a new type of power module for solving the above problems in the prior art.

In order to achieve the above purpose and other related purposes, the present application provides a power module, which at least includes: a metal casing, and a PCB board arranged in the metal casing; wherein, the PCB board is provided with at least a power switch tube, a first Screw holes, second screw holes, and gold finger connectors located next to the second screw holes; the first screw holes are pierced with grounding screws connected to the metal casing; the power switch tube produces After passing through the first screw hole, the ground noise will be transmitted to the second screw hole through the metal casing, and then sent to the outside of the power module through the golden finger connector.

In an embodiment of the present application, the bottom of the metal casing is provided with a threaded hole; the grounding screw is threaded through the first screw hole and connected to the threaded hole, thereby realizing the connection between the PCB board and the Single point connection to the metal housing.

In an embodiment of the present application, a position-limiting support part for fixing the position of the PCB board is disposed inside the metal casing.

In an embodiment of the present application, the PCB board is arranged parallel to the bottom surface of the metal casing.

In an embodiment of the present application, the first screw hole is disposed at an edge of the PCB.

In an embodiment of the present application, the first screw hole is disposed in the middle of the edge of the PCB board.

In an embodiment of the present application, the power switch tube is disposed beside the first screw hole.

In an embodiment of the present application, the golden finger connector is disposed on the other side of the PCB board opposite to the first screw hole.

In an embodiment of the present application, the second screw hole is disposed at an edge of the PCB board.

As mentioned above, the power module of the present application has the following beneficial effects:

1) The metal shell is used as the power ground, which reduces the number of PCB layers and saves the cost of PCB boards;

2) The power ground and the signal ground are well isolated, and the switching noise will not affect the signal control circuit;

3) The high-frequency switching harmonics in the switching noise will be greatly attenuated on the metal casing, and the conduction interference will not affect the peripheral electronic equipment.

Description of drawings

FIG. 1 is a schematic structural diagram of a power module in an embodiment of the present application.

Component designation description

1 ground screw

2 PCB boards

201 power switch tube

202 First screw hole

203 Second screw hole

204 gold finger connector

3 metal case

301 limit support part

302 threaded hole

Detailed ways

Embodiments of the present application are described below through specific examples, and those skilled in the art can easily understand other advantages and effects of the present application from the content disclosed in this specification. The present application can also be implemented or applied through other different specific implementation modes, and various modifications or changes can be made to the details in this specification based on different viewpoints and applications without departing from the spirit of the present application. It should be noted that, in the case of no conflict, the following embodiments and features in the embodiments can be combined with each other.

It should be noted that the diagrams provided in the following embodiments are only schematically illustrating the basic idea of the application, and only the components related to the application are shown in the diagrams rather than the number, shape and Dimensional drawing, the type, quantity and proportion of each component can be changed arbitrarily during actual implementation, and the component layout type may also be more complicated.

In the design of the existing PCB board, a complete ground is generally reserved for the power ground, and there are certain requirements for the area and thickness of the power ground, so that the high-frequency harmonics in the switching noise are attenuated in the ground On the plane, the PCB board will be a multi-layer board design, and the area of the PCB also needs to be increased, and sometimes the copper thickness of the ground layer also needs to be increased, so that the cost of the PCB board will increase significantly. In view of this, the present application proposes a new power module to solve this problem, specifically: treat the metal case as a complete ground plane. Since the area and thickness of the metal shell are larger than that of the PCB ground layer, it is more in line with the demand for power ground.

Please refer to FIG. 1 , this embodiment provides a power module. The power module includes: a PCB board 2 and a metal casing 3 , and the PCB board 2 is arranged in the metal casing 3 . In order to realize the fixed position of the PCB board 2 , a limit support part 301 can be provided on the side wall inside the metal casing 3 , preferably, the PCB board 2 is parallel to the bottom surface of the metal casing 3 .

The PCB board 2 is provided with a power switch tube 201 , a first screw hole 202 , a second screw hole 203 , a golden finger connector 204 , and other electronic circuit components. In detail: the first screw hole 202 can be set at the edge of the PCB board 2, preferably in the middle; the power switch tube 201 can be set next to the first screw hole 202; the gold finger The connector 204 can be arranged on the other side of the PCB 2 opposite to the first screw hole 202; a second screw hole 203 is arranged beside the golden finger connector 204; the second screw hole 203 It can be arranged at the edge position of the PCB board 2 .

The first screw hole 202 is pierced with the ground screw 1 connected with the metal casing 3 . The ground noise generated by the power switch tube 201 passes through the first screw hole 202, then passes through the metal casing 3 and is transmitted to the second screw hole 203, and then is sent to the external to the power module.

In addition, the bottom of the metal casing 3 may also be provided with a threaded hole 302 . The ground screw 1 passes through the first screw hole 202 and is threadedly connected with the threaded hole 302 , so as to realize a single-point connection between the PCB board 2 and the metal casing 3 .

To sum up, the power module of the present application reduces the number of PCB layers and saves the cost of the PCB board. The power ground is the metal shell, and the signal ground is on the PCB board, and they are connected at a single point through screw holes. In this way, the high-frequency harmonics in the switching noise will be greatly attenuated on the casing, and the conduction interference will not affect the surrounding electronic equipment. At the same time, the power ground and signal ground are well isolated, and switching noise will not affect the signal control circuit. Therefore, the present application effectively overcomes various shortcomings in the prior art and has high industrial application value.

The above-mentioned embodiments are only illustrative to illustrate the principles and effects of the present application, but are not intended to limit the present application. Any person familiar with the technology can modify or change the above-mentioned embodiments without departing from the spirit and scope of the present application. Therefore, all equivalent modifications or changes made by those skilled in the art without departing from the spirit and technical ideas disclosed in the application shall still be covered by the claims of the application.

Claims (9)

1. a kind of power module, which is characterized in that include at least：Metal shell, the pcb board being set in the metal shell； Wherein, at least provided with power switch pipe, the first screw hole, the second screw hole and positioned at second screw on the pcb board Golden finger connector beside hole；The earthing screw being connect with the metal shell is equipped in first screw hole；It is described After the Earth noise that power switch pipe generates is by first screw hole, described second can be passed to by the metal shell Screw hole, then it is sent to by the golden finger connector outside of the power module.

2. power module according to claim 1, which is characterized in that the bottom of the metal shell is provided with threaded hole； The earthing screw is connected through a screw thread after passing through first screw hole with the threaded hole, so as to fulfill the pcb board and The single-point connection of the metal shell.

3. power module according to claim 1, which is characterized in that be provided in the metal shell for described in fixation The limited support portion of the position of pcb board.

4. power module according to claim 1, which is characterized in that put down the bottom surface of the pcb board and the metal shell Row setting.

5. power module according to claim 1, which is characterized in that first screw hole is arranged on the pcb board Marginal position.

6. power module according to claim 5, which is characterized in that first screw hole is arranged on the pcb board The middle part at edge.

7. power module according to claim 5, which is characterized in that the power switch pipe is arranged on first screw The side in hole.

8. power module according to claim 5, which is characterized in that the golden finger connector is arranged on the pcb board The another side opposite with first screw hole.

9. power module according to claim 8, which is characterized in that second screw hole is arranged on the pcb board Marginal position.