JPH02125603A - Four-terminal chip type solid state electrolytic capacitor - Google Patents

Abstract

PURPOSE:To unnecessitate the attention about directivity at the time of packaging and mounting, improve the reliability of mounting, and reduce electric loss by making two terminals of inside and two terminals of outside have different polarities with each other. CONSTITUTION:An anode lead wire 2 of a capacitor element 1 is welded to an external terminal 3 of anode; a cathode layer of the capacitor element 1 is connected with an external terminal 5 of cathode by using conductive adhesive agent 4; molding and packaging are performed by transfer molding; each of the external terminals 3, 5 are cut off and subjected to forming. The external terminal 3 of anode is bifurcated into two branches, passes around behind a bottom surface from one side surface; the two branches are arranged in the inner side of external four-terminals, and turned into anode terminals 6, 7. The external terminal 5 of cathode reaches the bottom surface from both facing side surfaces, are arranged in the outer side of the external four-terminals, and turned into cathode terminals 8, 9. Thereby, the careful attention about directivity at the time of packing and mounting is unnecessitated, the reliability of mounting is improved, and electric loss can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a four-terminal chip type solid electrolytic capacitor, and more particularly to the structure of a terminal portion of a four-terminal chip type solid electrolytic capacitor.

[Conventional technology]

Conventionally, a chip type solid electrolytic capacitor has a structure in which two external terminals are led out, for example, as shown in FIG. In the figure, 11 is a capacitor element, an anode external terminal 13 is connected to a lead wire 12 planted from the capacitor element, and a cathode external terminal 15 is bonded to the cathode layer of the capacitor element 11 with a conductive adhesive 14. Thereafter, it is covered with a covering material, and the exposed anode and cathode external terminals are bent along the outer wall to form an external connection part.

[Problem to be solved by the invention]

The conventional electrolytic capacitors mentioned above are polar components due to the electrical properties of their dielectrics. Therefore, the above-described chip type solid electrolytic capacitor has two terminals, and each terminal has a different polarity, so that it has directionality as an electronic component.

If an electrolytic capacitor is mounted in the wrong direction, it will cause a short circuit in the electrical circuit, resulting in a fatal failure. This can be prevented by devising packaging methods such as taping in the same direction, but there is a drawback that reverse mounting can occur due to packaging mistakes or malfunctions of the mounting machine.

The object of the present invention is to provide a four-terminal chip that does not cause incorrect mounting, eliminates the need to pay attention to directionality during packaging and mounting, and in addition improves mounting reliability and reduces electrical loss. An object of the present invention is to provide a type face-piece electrolytic capacitor.

[Means to solve the problem]

In the 4-terminal chip-type surface electrolytic capacitor of the present invention, one external terminal is led out from each of the opposing side surfaces, two external terminals are led out from one side surface adjacent to the opposing side surfaces, and each terminal is arranged to the bottom surface. The structure is characterized in that four external terminals are arranged substantially parallel to each other on the bottom surface.

A preferred embodiment of the present invention can be achieved by configuring the four external terminals arranged substantially parallel to each other, with the two inner terminals serving as anode terminals and the two outer terminals serving as cathode terminals.

〔Example〕

Next, the present invention will be explained with reference to the drawings. FIGS. 1(a) and 1(b) are a sectional view and a schematic diagram of an embodiment of the present invention.

First, a metal powder with valve action such as aluminum or tantalum is formed into a desired shape, vacuum sintered, and anodized. Next, a semiconductor layer such as manganese dioxide, and a conductive layer such as a graphite layer, paste layer, and solder layer are formed. The anode lead wire 2 of the capacitor element 1 on which the body layers have been sequentially formed is welded to the anode external terminal 3, the cathode layer of the capacitor element 1 is connected to the cathode external terminal 5 with a conductive adhesive 4, and a molded exterior is formed by transfer molding. Then, by cutting and forming each external terminal 3.5, a four-terminal chip type surface electrolytic capacitor of the present invention is obtained.

At this time, the anode external terminal 3 is divided into two parts, going from one side to the bottom, and the external 4 terminals are placed on the inside and become the anode terminals 6, 7, and the cathode external terminal 5 is placed on the bottom from both opposing sides and is placed on the outside. In the case of 4 terminals, the cathode terminal 8 is placed on the outside.
．． It becomes 9.

〔Effect of the invention〕

As explained above, in the present invention, since the two inner terminals and the two outer terminals have different polarities (), even if the orientation is changed by 180 degrees, they are mounted in the positive direction, so it is necessary to pay attention to the directionality when packaging and mounting. This has the effect of eliminating

(2) Furthermore, since there are two mounting surfaces for external terminals for each polarity, the reliability of mounting is improved.

(3) The mounting area is large and electrical loss can be reduced.

There are also other secondary effects.

[Brief explanation of drawings]

FIGS. 1(a) and (b) are a cross-sectional view and a schematic structural diagram of a four-terminal chip-type surface electrolytic capacitor according to an embodiment of the present invention, and FIG. 2 is a cross-sectional view of an example of a conventional chip-type solid electrolytic capacitor. be. 1.11... Capacitor element, 2, 12... Anode lead wire, 3, 13... Anode external terminal, 4.14...
Conductive adhesive, 5.15...Cathode external terminal, 6,7.
...Anode terminal, 8,9...Cathode terminal, 10.20...
・Exterior material.

Claims (2)

[Claims] (1) Lead out one external terminal from each side surface facing each other, lead out two external terminals from one side surface adjacent to the facing side surface, arrange each terminal up to the bottom surface, and connect the external terminals approximately parallel to each other at the bottom surface. A 4-terminal chip type solid electrolytic capacitor characterized by arranging 4 terminals. (2) A four-terminal chip type solid electrolytic capacitor according to claim 1, characterized in that, of the four external terminals arranged substantially in parallel, two inner terminals are anode terminals and two outer terminals are cathode terminals.