JPH0333042Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a chip resistor, and more particularly to a so-called multiple chip resistor in which a plurality of resistance elements are arranged adjacent to each other on a common ceramic substrate or the like.

FIG. 1 shows a conventional multiple chip resistor, and FIG. 2 shows a cross section taken along the line -- in FIG. A ceramic substrate 2 formed in a rectangular shape has a plurality of electrodes 4A, 4B formed on its surface and side surfaces at a constant insulating interval in the longitudinal direction, and a plurality of electrodes 4A, 4B are formed between each electrode 4A, 4B. As shown in FIG. 2, a resistor element 6 is individually formed, one end of which is overlapped with the electrode 4A and the other end of which is electrically connected to the electrode 4B. Then, the resistance element 6 and the electrodes 4A, 4
A part of the surface of B is covered with a protective film 8 made of an insulating material such as synthetic resin. Next, FIG. 3 shows how this type of resistor is mounted on a printed wiring board by face bonding. show. That is, a chip resistor is connected by solder 14 between wiring conductors 12A and 12B formed on the surface of printed wiring board 10, with protective film 8 facing printed wiring board 10.

This type of resistor aims to be compact, so between the adjacent electrodes 4A and 4A, the electrode 4
The interval between B and 4B is set narrowly. Therefore, when soldering is performed, the solder enters into the space between the electrodes 4A and 4A, and between the electrodes 4B and 4B, and short circuits are likely to occur due to the solder 14. The withstand voltage between the electrodes 4B and 4B is low. Moreover, when mounted on the printed wiring board 10, each electrode 4A,
A large space 16 is formed in the gap between the electrodes 4A and between the electrodes 4B and 4B, and impurities such as processing liquid and water during face bonding enter and remain in this space 16, and this impurities such as chip resistors etc. This may cause deterioration of characteristics.

Therefore, the object of this invention is to provide a chip resistor that improves the withstand voltage by eliminating the space between the electrodes, and prevents short circuits due to solder penetration and deterioration of characteristics due to impurity penetration.

That is, the chip resistor of this invention includes a plurality of electrodes arranged facing the surface of an insulating substrate and extending to the side surface of the insulating substrate, and a plurality of electrodes arranged on the surface of the insulating substrate. a plurality of resistance elements installed on the insulator substrate, and the electrode installed on the insulator substrate selectively covering a part of the electrode together with each resistance element, and exposed on the front and side surfaces of the insulator substrate. A protective film extends as an insulating member between the electrodes and protrudes from the electrode surface.

Hereinafter, this invention will be described in detail with reference to embodiments shown in the drawings.

FIG. 4 shows an embodiment of the chip resistor of this invention, and the same parts as those of the resistor shown in FIG. 1 are given the same reference numerals.

For example, a ceramic substrate 2 is used as an insulating substrate in this chip resistor, and a plurality of pairs of electrodes 4A and 4B are arranged facing each other on the surface of the ceramic substrate 2 with a constant insulating interval. Each electrode 4A, 4B is connected to a ceramic substrate 2.
is extended to the side. And each electrode 4
Between A and 4B, as shown in FIG.
A resistor element 6 is individually formed, one end of which is overlapped with the electrode 4B, and the other end of which is electrically connected to the electrode 4B.

Further, on the upper surface of the ceramic substrate 2, a protective film 8 is provided which selectively covers a portion of the upper surface of each electrode 4A, 4B together with each resistor element 6. This protective film 8 is formed of an insulating material such as synthetic resin,
A part of it is extended to the surface and side surface of the ceramic substrate 2 between the electrodes 4A and 4A and between the electrodes 4B and 4B.
18B is formed, and the ceramic substrate 2
Insulating portions 20A and 20B are formed on the side surfaces of. Further, the protective film 8 is formed thicker than the electrodes 4A and 4B, and is formed between the electrodes 4A and 4A and between the electrodes 4B and 4B.
The insulating parts 18A and 18B between them form a flat surface with the protective film 8 on the upper surface side of each resistance element 6, and the insulating parts 2
Since 0A and 20B are also formed thicker than electrodes 4A and 4B, insulating parts 18A, 18B, 20
A and 20B protrude from between the electrodes 4A and 4B, respectively, beyond the electrode surfaces in the thickness direction.

In this way, between the adjacent electrodes 4A, 4A, the electrode 4
Since the insulating parts 18A, 18B, 20A, and 20B are formed by selectively extending a part of the protective film 8 between B and 4B, when mounted on the printed wiring board 10 as shown in FIG. As shown in FIG. 3, the space 16 between the adjacent electrodes 4A, 4A is filled with the insulating part 18A, and the space 16 between the other adjacent electrodes 4B, 4B is filled with the insulating part 18A.
It will be filled by B. For this reason, electrode 4
It is possible to increase the withstand voltage between A and 4A and between electrodes 4B and 4B, and also prevent short circuits due to the intrusion of solder 14, and prevent the intrusion of face bonding treatment liquid, moisture, and other impurities that conventionally occur in the space. Since there is no residue, characteristic deterioration can be prevented and stable electrical characteristics can be maintained over a long period of time.

Further, an insulating part 20A is installed between one electrode 4A and 4A on the side surface side of the ceramic substrate 2 by an extension of the protective film 8, and an insulating part 20A is installed between the other electrodes 4B and 4B.
An insulating part 20B is installed between them by an extension of the protective film 8, and each insulating part 20A, 20B protrudes from the electrode surface of each electrode 4A, 4B.
Together with the insulating parts 18A and 18B, the withstand voltage between the adjacent electrodes 4A and 4A and between the electrodes 4B and 4B can be improved, and short circuits due to solder can be prevented.

And each insulating part 18A, 18B, 20A, 2
0B is a protective film 8 installed on the upper surface of the resistor element 6.
Since it can be formed by extending the
The insulation between B can be processed in the same process without requiring a special process.

In addition, insulating parts 18A, 18B, 20A, 20B
may be formed of an insulating member different from the protective film 8, and the protective film 8 may be extended, and similar effects can be expected.

As explained above, according to this invention, the following effects can be obtained.

(a) A protective film that selectively covers part of the surface of the electrode along with the resistive element is extended as an insulating member between the electrodes exposed on the surface and side surfaces of the insulating substrate, and is made to protrude from the electrode surface. , the space that conventionally occurred between electrodes can be removed by using an insulating member, increasing the withstand voltage between the electrodes, and preventing short circuits and impurity intrusion due to solder, improving reliability. At the same time, stable electrical characteristics can be maintained.

(b) In addition, since the insulating member between the electrodes is formed by extending the protective film, the insulation between the electrodes can be achieved at the same time as the formation of the protective film, and no special treatment process is required. Chip resistors with high voltage and high reliability can be manufactured at low cost.

[Brief explanation of the drawing]

Figure 1 is a perspective view showing a multiple chip resistor, Figure 2
The figure is a sectional view taken along the line -- of the multiple chip resistor shown in Figure 1, Figure 3 is a perspective view showing the mounting state of the multiple chip resistor shown in Figure 1, and Figure 4 is a cross-sectional view of the multiple chip resistor shown in Figure 1. FIG. 2 is a perspective view showing an example of a resistor. Fifth
This figure is a perspective view showing the state in which the chip resistor shown in FIG. 4 is mounted. 2... Ceramic substrate (insulator substrate), 4A,
4B... Electrode, 6... Resistance element, 8... Protective film,
18A, 18B, 20A, 20B...Insulating section (insulating member).

Claims (1)

[Claims for Utility Model Registration] A plurality of electrodes arranged opposite to the surface of an insulating substrate and extending to the side surface of the insulating substrate, and installed between the electrodes on the surface of the insulating substrate. between the plurality of resistive elements and the electrode, which is installed on the insulating substrate so as to selectively cover a part of the electrode together with each resistive element, and is exposed on the front and side surfaces of the insulating substrate. A chip resistor comprising a protective film extending as an insulating member and protruding from an electrode surface.