JPS5885557A - Hybrid thick film integrated circuit - Google Patents

Abstract

PURPOSE:To improve the assembling workability by covering only a pad for measuring an element irrespective of soldering with insulating resin coating in a plurality of pads for connecting electric parts and measuring the element in a thick film circuit board, thereby reducing the soldering bridge. CONSTITUTION:A pad 8 for measuring an element of pads 7, 8 for connecting parts and measuring element is not necessary after through a trimming step, but has a danger of shortcircuiting in a soldering step. Accordingly, insulating resin 4 is covered so as not to expose it, thereby providing soldering resist function.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an insulating resin code I5 code pattern for a hybrid thick film integrated circuit.

Hybrid integrated circuits have recently become extremely compact, high-density, and practical.

The number of electrical components mounted on thick film substrates is also increasing. For this reason, the spacing between the soldering pads becomes narrower, and a solder bridge occurs during one soldering process, causing a problem of "shout" defects due to soldering.

Figure 1 (al % fbl, Figure 2 (al, (bl) shows the prior art, Figure 1 (at is a plan view of main parts of a thick film circuit board, Figure 1 fbl is A of Figure 1 fat) -A' is a sectional view, and Figure 2 (a+' is a component assembly diagram of a hybrid integrated circuit in which electrical components are mounted on a thick film circuit board made of aluminum and soldered). 2(b) is B- in Fig. 2 [al.
This is a cross-sectional view taken along B'.

The thick film circuit shown in FIG. 1 (al) is made by printing and firing a conductor consisting of a conductor 2 on a ceramic substrate 01.

After that, the resistor 3 is printed and fired.

After trimming the resistor B if necessary, the insulating resin coat 4 is printed and cured by heating.

The transistor 51- is mounted on the thick film circuit board shown in FIG.
.

When forming a hybrid integrated circuit by mounting and soldering electrical components such as a capacitor 6, the electrical component connection pads 7a to 7
Because the distance between e and the device measurement band 80 is narrow, a solder bridge portion 10 occurs between the electrical component connection pad 7b and the device measurement pad 8 shown in FIG. was occurring.

The object of the present invention is to eliminate the above-mentioned drawbacks of the prior art when soldering thick film circuit boards.

The present invention aims to reduce the number of solder bridges in the circuit and improve the ease of assembly of hybrid integrated circuits.

In order to achieve the above object, the present invention covers only the device measurement pads unrelated to soldering among the plurality of electrical component connection pads and device measurement pads on a thick film circuit board with an insulating resin coat. 1) It reduces the number of places where solder adheres.

FIG. 6 shows a thick film circuit board according to an embodiment of the present invention;
4(b) is an assembly plan view of the main parts of a hybrid integrated circuit in which electrical components are mounted and soldered on the thick film circuit board of FIG. 6. It is a Cl cross-sectional view.

The thick film circuit board shown in Fig. 6 is made by printing and firing a conductor paste v on an alumina substrate to form a conductor consisting of a wiring conductor 2, and then printing and firing a resistor paste to form a resistor 3. Then, the resistance value of the resistor 3 is precisely trimmed as required, and then a thermosetting resin paste is printed and heated to harden to complete the process. In Fig. 3, among the component connection pads 7 and the element measurement pads 8, the element measurement pads 8 are not only unnecessary after the above-mentioned trimming process, but also have the risk of shorting during the half-fitting process. It has the following. Therefore, as shown in FIG. 6, the element measurement pad 8 is covered with an insulating resin so as not to be exposed, thereby providing a solder resist function. 1
() By doing this, when soldering, the number of solder (fi) parts will be reduced, and short-circuit defects caused by solder bridges will be reduced.

reduced.

By applying the present invention, it is possible to reduce short-circuit defects caused by solder bridges and the like during soldering of high-density mounted hybrid integrated circuits.

This has the effect of significantly improving soldering workability.

[Brief explanation of drawings]

Figure 1 is a diagram of the main parts of a conventional thick film circuit board, Figure 2 is a diagram of a conventional thick film circuit board with electrical components mounted on it, and Figure 6 is a diagram of the main parts of a conventional thick film circuit board.
The figure is a plan view of the main part of the thick film circuit board according to the present invention, and FIG. 4 is a drawing showing electrical components mounted on the thick film circuit board according to the present invention. 4... Insulating resin coat 7... Pad for electrical component connection 8... Pad for element measurement 9... Pad for electrical component connection]/Inner contact portion 10...
- Susuki, Patent Attorney, Handa Bridge Department 1) Toshiyuki = u 4 ・ O 2 Kuni (α) 5. 5 ・7bi ・ ぢ 2≦ a−g□□7′ ／／／／／／／／ ≦7 、／／／／ B ／／ ／ ／′／
BL:
Bi 7,7 0 a 1/////////
／／／／／／／／／! Sai 2 illustration soup filtration bacterium v

Claims (1)

[Claims] 1. Conductor wiring and resistors are printed and fired on a ceramic substrate, the resistors are trimmed, and an insulating resin coat is hardened and formed.Electrical components are formed on a thick film substrate. In the hybrid integrated circuit formed by soldering, there are a plurality of connection pads for circuit connection of the electrical components and a plurality of element measurement pads for measuring resistance values, etc., and the trimming of the resistor is completed. After that, the insulating resin. - A hybrid thick film integrated circuit characterized in that the element measuring pad is covered with a pad.