JPS63220594A - Electronic circuit adjustment - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method for adjusting electronic circuits such as thick film integrated circuits which are often used in electronic devices such as video tape recorders that require miniaturization.

Conventional technology In recent years, the demand for smaller, lighter, thinner, and more sophisticated electronic devices has been increasing, and as a result, how to increase the density of the electronic circuits in these devices has become an extremely important issue. It's coming.

Under these circumstances, the conventional method of mounting electronic circuits that has been commonly used is to divide one electronic circuit into several functional circuits and integrate the circuit elements that make up each functional circuit. There is a mounting method in which a circuit block is constructed by converting the electronic circuit into a circuit block, and this circuit block is mounted on a printed wiring board to construct an electronic circuit.

In particular, in electronic circuits that incorporate this concept of functional circuitization, it is necessary to adjust the circuit characteristics of each functional circuit. Particularly in thick-film integrated circuits, so-called trimming, such as cutting out the area of printed resistors, is performed to improve the circuit characteristics. Many functional trimming methods are used to adjust characteristics.

Hereinafter, an electronic circuit adjustment method using the conventional function trimming method described above will be described from Kotobuki to Section 3 with reference to the drawings. As shown in FIG. 4, the thick film integrated circuit uses a so-called thick film circuit board in which a conductive paste or a printing paste is printed and fired on the surface of a ceramic substrate 1 to form circuit conductors 2 and printed resistors 3. Printed resistor 3 for adjusting circuit characteristics
In this case, the printing area is set large, that is, the resistance value is set small in advance, taking into account variations in circuit characteristics. after that,
An electronic circuit adjustment method has been used in which electronic components 4 necessary to configure a circuit block having a desired function are mounted, and printed resistors 3 are trimmed to obtain predetermined circuit characteristics. However, with the above conventional method, the printed resistor to be trimmed must be set in advance to a smaller resistance value as the printed area increases, taking into account variations in circuit characteristics. On the other hand, if the circuit operating range is narrow, there is a problem that the circuit will not operate in the state before the printed resistor is trimmed, and it will not be possible to determine if the electronic component is defective. It is not until the electronic component is discarded that it is determined that it is defective, and as a result, the entire board must be discarded and discarded.

In view of the above problems, the present invention provides an electronic circuit adjustment method that makes it possible to check the operation of a circuit block before applying printed resistance 1-'J mink to a circuit block with any characteristics. The purpose is to

Means for Solving the Problems In order to achieve the above object, the electronic circuit adjustment method of the present invention provides a method for adjusting one end of the mark 1!11 resistor of a circuit board on which printed wiring is provided and a plurality of electronic components are arranged. A variable resistor is formed in an open state, and a variable resistor is connected between the other end of the printed resistor and a first portion connecting one end of the printed resistor, and the resistance value of the variable resistor is changed to ] Determine the first resistance value of the variable resistor that will give the electrical characteristics or predetermined characteristics of the circuit board, remove the variable resistor, and set the resistance value of the printed resistor to the first resistance value. and connect one end of the stamp resistor to the first part of MiJ.

Effect By installing a variable resistor whose resistance value can be varied over a wide range using the above adjustment method, the electronic circuit formed on the circuit board can be easily set in the operating range, and the electrical characteristics can be changed. A first resistance value of the variable resistor that provides predetermined characteristics can be determined. Furthermore, when characteristics are detected in order to determine the first resistance value, it becomes possible to determine whether or not the electronic components disposed on the circuit board are defective. Furthermore, since the resistance value to which the resistance value of the printed resistor should be set can be confirmed, the work of adjusting the resistance value of the printed resistor is facilitated.

EXAMPLE Hereinafter, an electronic circuit adjustment method according to an example of the present invention will be described with reference to the drawings. 1 and 2 are equivalent circuit diagrams illustrating an electronic circuit adjustment method according to an embodiment of the present invention.

In FIGS. 1 and 2, 5, 6.7 are terminals, and a printed resistor 8 is formed between the terminals 5 and 6. Note that the printed resistor 8 is set to have a large printed area, that is, a small resistance value, in order to adjust the circuit characteristics. 9 is a variable resistor.

When adjusting the characteristics of the electronic circuit with the above configuration, do not change the terminal 6.
A variable resistor 9 is attached between the terminal 7 and the terminal 7, and the resistance value R9 of the variable resistor 9 is changed to obtain a resistance value RO that provides a predetermined circuit characteristic.
(Figure 1).

Next, the variable resistor 9 is removed, the printed resistor 8 is trimmed, and the resistance value R8 of the printed resistor 8 is set to the resistance value R8 obtained as described above.
After that, connect terminal 5 and terminal 70 with a jumper lead or the like (Fig. 2).

A case in which the above electronic circuit adjustment method is applied to an electronic circuit made of a thick film integrated circuit will be described with reference to FIG.

In FIG. 3, 1o is a ceramic substrate, and a conductor paste or a resistor paste is printed and fired on the surface of this ceramic substrate 6 to form circuit conductors 11 and printed resistors 8. A printed resistor 8 is formed between the terminals 5 and 6, and lead terminals 12 provided on both sides of the ceramic substrate are connected to terminals of an electronic component 13 via a circuit conductor 11 and a printed resistor 8, respectively. . The printed wiring board 14 on which the ceramic substrate 10 is mounted is provided with fitting holes 15 into which the lead terminals 12 are fitted, and the terminals 5 and 5 in these fitting holes 16 are provided.
Fitting holes 15a and 15b into which lead terminals 12 respectively connected to 7 are fitted are connected by printed wiring 16.

When adjusting the electronic circuit with the above configuration, first, the lead terminals 12 and the printed wiring board 14 are insulated, and the variable resistor 9 is attached between the terminals 6 and 70.

Next, the characteristics of the electronic circuit formed on the ceramic substrate 10 are measured while changing the resistance value R9 of the variable resistor 9, and a resistance value RO that provides predetermined characteristics is determined.

Then, remove the variable resistor 9 from the ceramic substrate 1o,
The printed resistor 8 is trimmed to set the resistance value R8 of the printed resistor 8 to the resistance value RO. Then, the ceramic substrate 10 is mounted on the printed wiring board 14, thereby adjusting the characteristics of the electronic circuit.

Therefore, according to this embodiment, the variable resistor 9 is attached,
By changing the resistance value of the variable resistor 9, it is easy to set the electronic circuit formed on the ceramic substrate 10 in the operating region, and the resistance value of the variable resistor 9 that provides predetermined characteristics can be easily determined. becomes possible. At the time when the characteristics of the broken electronic circuit are measured, it is possible to determine whether the electronic component 8 is defective. Furthermore, the resistance value to which the resistance value of the printed resistor 8 should be set becomes clear, and trimming can be easily performed. As a result, the yield of electronic circuits is improved, and the adjustment of the characteristics of electronic circuits becomes more accurate and easier than before.

Effects of the Invention According to the present invention, one end of the printed resistor of the circuit board is formed open, and a variable resistor is attached between the dragon end of the printed resistor and the first part connecting the one end of the printed resistor. To the first resistor 9, which changes the resistance value of the variable resistor so that the electrical characteristics of the circuit board become predetermined characteristics.

Since the resistance value of the printed resistor was determined and the resistance value of the printed resistor was adjusted to the first resistance value, a variable resistor was attached and the characteristics were measured, thereby controlling the electronic circuit formed on the circuit board to the operating range. This makes it easy to set the first resistance value to have a predetermined characteristic. Further, in the process of measuring the characteristics of the electronic circuit and determining the first resistance value, it is possible to determine whether or not the electronic components disposed on the circuit board are defective.

At this point, the resistance value to which the resistance value of the printed resistor should be set becomes clear, so the adjustment work of the resistance value of the printed resistor becomes more accurate and easier than in the past. As a result, the yield of electronic circuits and workability are improved.

[Brief explanation of the drawing]

1 and 2 are equivalent circuit diagrams illustrating an electronic circuit adjustment method according to an embodiment of the present invention, and FIG. 3 is a perspective view of a printed wiring board to which the electronic circuit adjustment method according to an embodiment of the present invention is applied. Figure, λ4 is a perspective view of the printed circuit board 11 to which the conventional electronic circuit adjustment method is applied.
0...Ceramink board, 11...Circuit conductor, 13...Electronic component, 14...Printed wiring board. Name of agent: Patent attorney Toshio Nakao and 1 other person 2nd
Figure 13-Electric': + Shubai + 4-67 thousand distribution map 3 f3f/7f. JP-A n, '1B3-22D594 (4) Figure 4 □

Claims (1)

[Claims] A first printed resistor is formed with one end of a printed resistor in an open state on a circuit board on which printed wiring is provided and a plurality of electronic components are arranged, and the other end of the printed resistor is connected to one end of the printed resistor.
A variable resistor is connected between the variable resistor and the variable resistor, the resistance value of the variable resistor is changed to determine a first resistance value of the variable resistor at which the electrical characteristics of the circuit board become predetermined characteristics, An electronic circuit adjustment method comprising removing a resistor, adjusting the resistance value of the printed resistor to the first resistance value, and connecting one end of the printed resistor to the first portion.