JPH0433657Y2 - - Google Patents

Description

[Detailed description of the invention] Industrial field of application The invention uses large connection terminals through which a relatively large current flows between boards arranged in multiple stages above and below to connect with external equipment. The present invention relates to a power semiconductor device that is electrically connected to each other, and particularly relates to a connection structure for efficiently soldering a board and a connection terminal.

Prior Art What is shown in FIGS. 2 and 3 is an example of a conventional power semiconductor device packaged.
A power circuit board 2 in which semiconductor elements 1 such as transistors and diodes are arranged and connected on a wiring pattern.
and a control circuit board 6 to which switches and other various electrical components 5 are arranged and connected on a wiring pattern are arranged in two stages via a resin outer frame 3 for molding, and the power circuit board 2 is placed in the mold. It is fixed to the resin outer frame 3 with an internal casting resin 4 such as silicone gel, and a final sealing resin 7 such as epoxy resin is used.
The entire structure was fixed by injection hardening.

The flat external input/output terminals 8, 8, . 6 and its end protrudes outward, and the external input/output terminal 8 is used to connect to an external device.

Problems with the Prior Art Since the external input/output terminal 8 as described above is for connecting with an external device as described above, it must be subjected to a certain amount of external force so that the terminal can be inserted or removed. In order to withstand the current, it is necessary to flow a relatively large current in the power circuit, so it has a relatively large flat plate shape as shown in Figure 4a and b, and in conventional power semiconductor devices, the external input/output The terminal 8 and the control circuit board 6 are connected to the fourth
As shown in FIG. b, the external input/output terminal 8 is electrically connected by soldering 10 over the entire length of the outer periphery. However, when performing the soldering 10 as described above, the heat during soldering is transferred to the external input/output terminal 8 itself and the power circuit board 2 to which this external input/output terminal 8 is connected, and is radiated. Therefore, there is a problem that good soldering may not be achieved.

Purpose of the invention Therefore, the purpose of the present invention is to prevent excess heat from being dissipated during soldering, and to
An object of the present invention is to provide a power semiconductor device having a structure that enables an improvement in yield during soldering.

Structure of the invention The main means adopted by the invention to achieve the above object is to connect the power circuit board and the control circuit board, which are arranged vertically in multiple stages, with an external In a power semiconductor device electrically connected by input/output connection terminals, the control circuit board is passed through the body of the connection terminal in a non-conducting state, and a side part of the connection terminal is provided with: A sub-terminal having an L-shape in side view and narrower than the connecting terminal is integrally attached, and the extending portion reaching the tip of the sub-terminal is separated from the control circuit board, so that only the tip is controlled as described above. This is a power semiconductor device that is soldered to a circuit board to electrically connect the boards to each other.

Embodiments Next, embodiments embodying the present invention will be described with reference to FIGS. 1a and 1b to provide an understanding of the present invention. FIG. 1 shows an inter-board connection structure of a power semiconductor device according to an embodiment of the present invention, and FIG. 1A is a front view showing an example of external input/output terminals that can be used in the connection structure. 4B is a view corresponding to FIG. 4B showing how the external input/output terminals are attached to the power semiconductor device.

Note that the same reference numerals are used for the same elements as those of the prior art shown in FIGS. 2 to 4.

The following examples are merely specific examples of the present invention, and are not intended to limit the technical scope of the present invention.

The main difference between the embodiment shown in FIG. 1 and the conventional example shown in FIGS. 2 to 4 is that, as shown in FIG. 1a, the external input/output terminal 8a has a
The point is that the small sub-terminal 11, which is L-shaped when viewed from the side, is integrally attached. The width l at the connection part of the sub-terminal 11 with the external input/output terminal 8a is:
The width L of the external input/output terminal 8a at the connection part with the sub-terminal 11 is much smaller than the width L, and therefore, the heat applied to the tip of the sub-terminal 11 is
Since the resistance during transmission is large, the amount of heat radiated toward the external input/output terminal 8a is extremely small.

As shown in FIG. 1b, the external input/output terminal 8a integrally provided with the above-mentioned sub-terminal 11 has a main body part that is controlled in the same way as in the conventional example shown in FIG. By inserting it into the insertion hole 12 provided in the circuit board 6, it is mechanically fixed to the control circuit board 6. In this case, external input/output terminal 8
The body portion of a and the control circuit board 6 are in a non-conducting state. Further, the tip of the sub-terminal 11 is inserted into a sub-terminal insertion hole 13 bored adjacent to the mounting hole 12 into which the body of the external input/output terminal 8a is inserted, and the control circuit is connected by soldering 14. It is electrically connected to the substrate 6.

As mentioned above, the external input/output terminal 8a is connected to the control circuit board 6 via the small sub-terminal 11 with poor thermal conductivity.
Since the soldering is performed 14, heat during soldering is difficult to be transmitted to the external input/output terminal 8a through the sub-terminal 11, and therefore failures in soldering due to heat radiation are significantly reduced. Furthermore, in the device of this embodiment, only the tip of the sub-terminal 11 is electrically connected to the control circuit board 6, and the extending portion of the sub-terminal 11 to the tip is separated from the control circuit board 6. Therefore, heat does not escape to the control circuit board 6 through this portion (see FIG. 1b), and the soldering work can be performed extremely well.

As mentioned above, in the present invention, in order to avoid heat from the connection terminals such as the external input/output terminal 8a, a small sub-terminal is provided on the connection terminal, and only the tip of the sub-terminal is soldered to the control circuit board. The structure of the sub-terminals is not limited to that shown in Fig. 1, as the aim is to minimize heat dissipation during soldering.
Various forms are possible.

Further, the number of stages of boards is not limited to the two stages shown in the above embodiment, but may be three or more stages, and the connection terminals are electrically connected to these boards via sub-terminals.

Effects of the Invention As described above, the present invention provides connection terminals for external input/output that are installed upright on the power circuit board in a conductive state between the power circuit board and the control circuit board arranged in multiple stages above and below. In the power semiconductor device, the body of the connection terminal is passed through the control circuit board in a non-conducting state, and the side part of the connection terminal has a width wider than the connection terminal. An L-shaped sub-terminal is integrally attached when viewed from a narrow side, and an extended portion reaching the tip of the sub-terminal is separated from the control circuit board, and only the tip is soldered to the control circuit board. Since this is a power semiconductor device in which the boards are electrically connected to each other, sub-terminals are used to solder the connection terminals to the board. This prevents heat dissipation from the solder and significantly improves the soldering success rate. Further, in the device according to the present invention, only the tip of the sub-terminal is electrically connected to the control circuit board, and the extending portion of the sub-terminal to the tip is separated from the control circuit board. Heat does not escape to the control circuit board through this part, and the soldering work can be performed extremely well.

[Brief explanation of drawings]

FIG. 1 shows an inter-board connection structure of a power semiconductor device according to an embodiment of the present invention.
2 is a front view showing an example of a connecting terminal that can be used in the same connection structure, FIG.
The figures relate to the connection structure between the boards of a conventional power semiconductor device.
The plan view in the figure, Figure 4 is A- in Figure 3.
It is a sectional view taken along arrow A (a view corresponding to FIG. 1b). Explanation of symbols, 2...Power circuit board, 6...Control circuit board, 8a...External input/output terminal (connection terminal), 11...Subterminal, 12...Mounting hole, 13...
...Subterminal insertion hole, 14...Soldering.

Claims (1)

[Scope of Claim for Utility Model Registration] Electrical connection between a power circuit board and a control circuit board arranged in multiple stages above and below through connection terminals for external input/output installed in a conductive state on the power circuit board. In the power semiconductor device, the body of the connection terminal passes through the control circuit board in a non-conducting state, and a side part of the connection terminal has a width narrower than the connection terminal in side view. An L-shaped sub-terminal is integrally attached, the extending portion reaching the tip of the sub-terminal is separated from the control circuit board, and only the tip is soldered to the control circuit board to connect the boards to each other. A power semiconductor device that is electrically connected.