JPH0635382Y2 - Lead terminal mounting structure for hybrid integrated circuit - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a lead terminal mounting structure for a hybrid integrated circuit that employs a metal insulating substrate.

[Conventional technology]

FIG. 3 shows a conventional lead terminal mounting structure for a hybrid integrated circuit. In the figure, 1 is a metal insulating substrate formed by coating a metal plate 1a with an insulating layer 1b such as resin, 2 is a terminal mounting land of a circuit pattern formed on the upper surface of the substrate 1, 3 is a lead terminal for external drawing, 4 is a solder joint. That is, in the conventional structure, a round lead or a flat lead wire is used as the lead terminal 3 and the tip of the lead terminal 3 is soldered to the terminal mounting land 2.

[Problems to be solved by the device]

By the way, in the lead terminal mounting structure in which the round lead or the flat lead wire is soldered on the substrate as described above, there are the following difficulties in the manufacturing process. That is, when connecting the lead terminal 3 to the terminal mounting land 2 on the substrate by the reflow soldering method, it is necessary to temporarily hold the lead terminal 3 at a predetermined position using a jig or the like during the reflow soldering process. However, the work process is troublesome. There is also a method of manually soldering using a soldering iron, but the work efficiency is low and not suitable for mass production.

On the other hand, a clip type lead is used as the lead terminal, and similarly to the lead terminal mounting structure for a ceramic substrate, the clip type lead is sandwiched at the peripheral edge of the substrate and temporarily fixed, and then soldered to the terminal mounting land. Later, we also tried a terminal mounting method that cuts the clip jaw on the play side, which is in contact with the metal plate of the metal insulating board, from the root so that it floats from the metal surface of the board, but with this method, cutting the clip jaw is a manual operation. Therefore, the work efficiency is low and it is not suitable for mass production.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and an object thereof is to provide a lead terminal mounting structure capable of connecting lead terminals in a simple working process for a hybrid integrated circuit using a metal insulating substrate. And

[Means for Solving the Problems]

In order to solve the above problems, the lead terminal mounting structure of the present invention has a thickness of 0.05 to 0.2 mm between the metal surface of the metal insulating substrate and the clip type lead terminal, and the clip portion of the clip type lead terminal and the clip section. A clip-type lead terminal is sandwiched around the periphery of the substrate so that one end of the lead terminal and the terminal-side mounting land on the circuit side are in contact with each other with an insulating sheet having a size only in contact with the metal surface interposed therebetween. Solder joints shall be made between the lead terminals and the circuit terminal mounting lands.

[Action]

As in the above structure, by interposing an insulating sheet between the metal surface of the board and the clip-type lead terminal except for the clip jaws that come into contact with the terminal mounting lands on the board, the lead terminal is obstructed with respect to the board. It can be temporarily fixed without a lead terminal, and the metal surface of the board and the lead terminal are electrically insulated by an insulating sheet when the lead terminal is mounted.
After soldering the lead terminal, it can be used as a product without cutting the clip jaw on the play side.

The insulating sheet is preferably made of polyimide, polyester, silicone resin film, etc. as a material that can withstand the heating temperature during soldering and solvent cleaning after soldering, and is thick considering the withstand voltage. 0.05 ~
Select the one with about 0.2 mm. Also, after cutting the insulating sheet to the required size, it is either attached to the metal surface of the board in advance, or temporarily set on the clip type lead, and the clip type lead is attached to the board, and the spring force of the clip is used to attach the insulating sheet to the board. It should be sandwiched between the metal surface and the lead.

〔Example〕

1 and 2 show different embodiments of the present invention, and the same members corresponding to those in FIG. 3 are designated by the same reference numerals.

First, FIG. 1 shows an embodiment in which a hybrid integrated circuit is formed on one surface of a substrate 1. As a lead terminal, a clip-type lead terminal 5 having upper and lower bifurcated clip jaws 5a and 5b is adopted, Clip jaw on the upper side of the metal insulating substrate 1
5a is sandwiched and mounted on the peripheral edge of the substrate so that the terminal 5a contacts the terminal mounting land 2. In order to prevent the lead terminal 5 from directly contacting the metal plate 1a of the substrate 1, an insulating sheet 6 is provided between the lead terminal 5, especially the lower clip jaw 5a and the metal plate 1a of the substrate 1. It is sandwiched, and in this mounted state, the upper clip jaw 5a and the terminal mounting land 2 are soldered by the reflow soldering method.

Here, the insulating sheet 6 has a thickness of 0.05 to 0 in consideration of withstand voltage.
A resin film of 2 mm is used, and after being cut to the required size, it is attached to the metal plate 1a of the substrate 1 on the lower surface and peripheral surface area where the lead terminals 5 come into contact with an adhesive, or a clip-type lead. When the lead terminal 5 is set on the clip jaw 5b of the terminal 5 and the lead terminal 5 is mounted on the board 1, the insulating sheet 6
Is sandwiched and fixed between the metal surface of the substrate 1 and the lead terminal 5.

FIG. 2 shows an embodiment in which a hybrid integrated circuit is formed on both sides of the substrate 1. In this embodiment, the insulating sheet 6 is the metal insulating substrate 1.
On the other hand, it is interposed between the peripheral end surface of the metal plate 1a and the lead terminal 5 to prevent contact with the lead terminal 5. In this state, the upper and lower clip jaws 5a, 5b of the lead terminal 5 and the circuit side Is soldered to the terminal mounting land 2.

After soldering the lead terminals 5 in each of the above-described embodiments, a resin coating is applied to the surface of the substrate, and the entire circuit including the lead mounting portion is resin-sealed.

[Effect of device]

The lead terminal mounting structure according to the present invention has the following effects by being configured as described above.

That is, a clip-type lead terminal is used as the lead terminal, and an insulating sheet is interposed between the lead terminal and the metal insulating substrate in a state where the lead terminal is mounted on the metal insulating substrate. By soldering between the terminal mounting land and the lead terminal, it is possible to temporarily fix the lead terminal to the board without the need for a special jig during the soldering process, and between the metal surface of the board and the lead terminal. Since it is electrically insulated by an insulating sheet, it can be used as a product as it is without cutting the play side clip jaw after soldering. As a result, the process of assembling the hybrid integrated circuit can be simplified and the productivity can be greatly improved.

[Brief description of drawings]

FIG. 1 and FIG. 2 are cross-sectional views of the essential part of different embodiments of the present invention, and FIG. In the figure, 1: metal insulating substrate, 1a: metal plate, 1b: insulating layer, 2: terminal mounting land, 4: solder joint part, 5: clip type lead terminal, 6: insulating sheet.

Claims (1)

[Scope of utility model registration request] 1. A lead terminal mounting structure for a hybrid integrated circuit using a metal insulating substrate, wherein the clip type lead terminal has a thickness of 0.05 to 0.2 mm between a metal surface of the metal insulating substrate and the clip type lead terminal. The peripheral edge of the substrate is such that one end of the lead terminal and the circuit side terminal mounting land are in contact with each other with an insulating sheet having a size only at the portion where the sandwiched portion and the metal surface come into contact with each other. A lead terminal mounting structure for a hybrid integrated circuit, characterized in that the lead terminal and the circuit side terminal mounting land are soldered together.