JPH097491A - Electronic fuse - Google Patents

Abstract

PURPOSE: To improve workability, and reduce cost without using a gold wire by printing and forming patterning whose central part is composed of neck- shaped solder cream between copper foil electrodes on an insulating film. CONSTITUTION: A solder cream pattern 14 where electrodes 12 and 13 which are oppositely arranged so as to separate from each other and are composed of copper foil are electrically continued with each other, is printed and formed on an insulating film 11. Since a central part 14a of the pattern 14 is thinly formed in a neck shape, when a large electric current flows between the electrodes 12 and 13, solder of the central part 14a melts, and it is disconnected by being pulled by both electrodes due to surface tension, and both electrodes are electrically discontinued with each other. Projecting parts of the electrodes 12 and 13 from the film 11 are formed external terminals. Normally, a part of the electrodes 12 and 13 and a surface of the pattern 14 are sealed by resin, and are cut off from an external part.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic fuse,
Particularly, the present invention relates to a structure of an electronic fuse which has high productivity and low cost.

[0002]

2. Description of the Related Art Conventionally, this type of electronic fuse has a structure shown in FIG.

In FIG. 5, reference numeral 1 is a resin mold plate, and 2,
3 is a lead having metal plate-shaped electrode portions 2a and 3a, 4 is a gold wire electrically connected to the electrode portions 2a and 3a of the leads 2 and 3, and 5 is a silicon-based inner resin that covers the gold wire 4. is there.

The electronic fuse having the above structure has leads 2, 3
When a large current flows between them, the gold wire melts and breaks,
The leads 2 and 3 are electrically disconnected.

[0005]

However, according to the above-mentioned conventional example, since the connection of the gold wire to the lead electrode is performed by the fusion bonding using the wire bonder, the productivity is poor, and the gold wire is not used. However, there is a problem that the cost becomes high because of the use of.

[0006]

The above-mentioned problems can be solved by printing a pattern consisting of a solder cream having a neck-shaped central portion between copper foil electrodes without using a gold wire.

[0007]

According to the above structure, since the pattern is formed by printing, the workability is improved and the productivity is improved, and since the solder cream is used instead of the gold wire, a low cost electronic fuse can be obtained.

[0008]

EXAMPLE Next, regarding the electronic fuse according to the present invention,
This will be described with reference to FIGS.

In FIG. 1 and FIG. 2, 11 is an insulating film mixed with an epoxy material, 12 and 13 are adhesively fixed on the film 11, and electrodes made of copper foil are arranged so as to be spaced apart from each other, and 14 is a film. Electrode 1 printed on 11
It is a solder cream pattern that electrically connects 2 and 13. Here, the pattern 14 is, as shown in FIG.
The central portion 14a is thin and formed in a neck shape.

The electronic fuse having the above structure has electrodes 12, 1
When a large current flows between the electrodes 3, the solder in the central portion 14a is melted and pulled by the electrodes 12 and 13 due to surface tension to break the wire, and the electrodes 12 and 13 are electrically disconnected. The portions of the electrodes 12 and 13 protruding from the film 11 form external terminals.

The electronic fuses shown in FIGS. 3 and 4 are the same as those shown in FIG.
A part of the electrodes 12, 13 of the electronic fuse and the pattern 14 of the solder cream in FIG. 2 are sealed with a resin 15 such as an epoxy resin so as to be shielded from the outside.

[0012]

As described above, according to the electronic fuse of the present invention, since the pattern of the solder cream having the neck shape in the central portion is formed by printing between the electrodes, the workability is improved and the productivity is improved. Further, since the solder cream is used without using the conventionally used gold wire, there is an advantage that a low-cost electronic fuse can be obtained.

[Brief description of drawings]

FIG. 1 is a plan view showing an electronic fuse according to the present invention.

FIG. 2 is a sectional view showing an electronic fuse according to the present invention.

FIG. 3 is a plan view showing a state in which an electronic fuse according to the present invention is resin-sealed.

FIG. 4 is a cross-sectional view showing a state in which the electronic fuse according to the present invention is resin-sealed.

FIG. 5 is a plan view showing a conventional electronic fuse.

[Explanation of symbols]

 11 Insulating film 12, 13 Electrode (copper foil) 14 Solder cream pattern 15 Resin

Claims (1)

[Claims] 1. An electronic fuse having a structure in which copper foil electrodes are spaced apart and opposed to each other on an insulating film, and a pattern made of a solder cream having a neck shape at the center is printed between the electrodes.