JPH1092690A - Capacitance adjusting equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a capacitance adjusting equipment wherein the adjusting work time of a capacitance is short, and its adjustment is performed easily, and it is made stable. SOLUTION: In this capacitance adjusting equipment, there is provided on a printed board PB a parallel circuit wherein a reference capacitor C1 with an arbitrary capacitance value and capacitors C2, C3,... with respective capacitance values being 2<x> times (x is an integer) as large as the capacitance value of the reference capacitor C1 are connected in parallel with each other via pattern cutting portions K1, K2,.... Then, employing as the minimum capacitance the capacitance of the reference capacitor C1 and employing as the maximum capacitance the total capacitance of all the capacitors C1, C2, C3,..., the pattern cutting portions K1, K2,... are cut selectively to adjust a desired capacitance value within the employed scope of capacitance values.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a capacitance adjusting circuit for adjusting a capacitance to an arbitrary capacitance value.

[0002]

2. Description of the Related Art Conventionally, a capacitance is adjusted using a trimmer capacitor or a streak is formed in a capacitor element using a laser beam, in other words, a required capacitance value is obtained by laser trimming. .

[0003]

In any of the above-mentioned prior arts, the adjusting operation time is long, the adjustment is difficult and the cost is high. In the former, there is a problem in the stability of the capacity.

[0004]

Since the present invention apparatus SUMMARY OF THE INVENTION To solve the above problems, a reference capacitor C1 with any capacitance value as shown in FIG. 1, 2 ^x (x of the capacitor C1 of this standard Capacitors C2 and C3 having an integer value
Are provided on the printed circuit board PB by connecting in parallel via the pattern cut portions K1, K2,..., The minimum capacitance is set as the capacitance of the reference capacitor C1, and the maximum capacitance is set to all capacitors C1, C2. .. the desired capacitance value in the range as the included capacitance of the pattern cut portions K1, K2
.. Are selected and cut for adjustment.

[0005]

FIG. 1 is a connection diagram showing the configuration of a first embodiment of the apparatus of the present invention. In the first embodiment, a reference capacitor C1 having an arbitrary capacitance value and capacitors C2 to C4 having a capacitance value of 2 ^x (x is an integer) of the reference capacitor C1 are connected via pattern cut sections K1 to K4. A parallel circuit formed in parallel is formed on the printed circuit board PB, and the capacitance of the capacitor C1 based on the minimum capacitance, for example, C
1 = 1 pF, and the maximum capacitance is the included capacitance of all the capacitors C1 to C4, for example, 15 pF and the range is 1 to 15 pF.
In the desired capacitance value in the pattern cut portion K, for example, 7 pF
Adjustment is made by selecting and cutting K4 from 1 to K4. When adjusting to a capacitance value of 2 pF, the pattern cut portion K
When adjusting the capacitance value to 10 pF by cutting 1, K3, and K4, the pattern cut portions K1 and K3 are cut, and the capacitance can be adjusted in the range of 1 to 15 pF in the same manner. That is, the capacitance of the parallel circuit is measured by the capacitance measuring unit MA,
While the capacitance is displayed on the capacitance display section DS, the pattern cut sections K1 to K4 are selected and cut by the cutting means CU so as to obtain a desired capacitance value, and the capacitance value is adjusted.

FIG. 2 is a connection diagram showing the configuration of a second embodiment of the apparatus of the present invention. This second form is a conveyor CV
, A capacity measuring unit MA for measuring the capacity at the measuring position, a capacity displaying unit DS, a capacity comparing unit CP for comparing the measured capacity with the set capacity, a capacity counting unit CT for counting a predetermined capacity, and a pattern. A cutting unit CU for cutting the cut portions K1 to K4 is provided. The capacity is set, the total capacity is measured by the capacity measuring unit MA, compared with the set capacity, and the predetermined capacity is counted by the capacity counting unit CT. In order to obtain a predetermined capacity, the pattern cut portions K1 to K4 are selected as described above and cut by the cutting means CU.

FIG. 3 is an explanatory diagram for adjusting the capacity by the apparatus of the present invention. A portion of about 5% to 20% of the target capacity value is adjusted by the apparatus of the present invention. For example, when the target capacitance value is 150 pF and the capacitance of about ± 10% is adjusted, 140 pF is set as the fixed capacitor Cf, C1 = 1 pF, C2 = 2 pF, C3 = 4 pF, C4.
= 8 pF is used as the adjustment capacitor. 140pF total capacity
+ 1pF + 2pF + 4pF + 8pF = 155pF. If there is an error in the 140pF capacitor itself, the error is adjusted by the 15pF capacitor of the present invention to 150pF.

[0008]

As described above, according to the present invention, since the capacitance of the capacitor connected in parallel is adjusted by selecting and cutting the pattern cut portion, the adjustment work time is short, the adjustment is easy, and the cost is low. It is possible to provide a capacity adjusting device having a stable capacity.

[Brief description of the drawings]

FIG. 1 is a connection diagram illustrating a configuration of a first example of an embodiment of a device of the present invention.

FIG. 2 is a connection diagram showing a configuration of a second example of the embodiment of the device of the present invention.

FIG. 3 is an explanatory diagram in the case of adjusting the capacity by the device of the present invention.

[Explanation of symbols]

 C1 Reference capacitor C2, C3 ... Capacitor K1, K2 ... Pattern cut section PB Printed circuit board MA Capacity measurement section DS Capacity display section CU Cut means CV Conveyor CP Capacity comparison section CT Capacity counting section Cf Fixed capacitor

Claims (4)

[Claims] 1. A parallel circuit formed by connecting a reference capacitor having an arbitrary capacitance value and a capacitor having a capacitance value of 2 ^x (x is an integer) of the reference capacitor in parallel via a pattern cut portion. Provided on the substrate, the minimum capacitance is the capacitance of the reference capacitor, the maximum capacitance is the included capacitance of all capacitors, a desired capacitance value in the range is adjusted by selecting and cutting the pattern cut portion. Capacity adjustment device. 2. The capacitance adjusting device according to claim 1, wherein a capacitance measuring unit is connected to the parallel circuit to measure a capacitance value. 3. The total capacity is measured by the capacity measuring unit,
3. The capacity adjusting device according to claim 2, wherein the counting section counts to a predetermined capacity value, and cuts the pattern cut section so as to have the counted capacity. 4. A capacity measuring unit for conveying a printed circuit board by a conveyor and measuring a capacity at a measuring position, a capacity comparing unit for comparing a measured capacity with a set capacity, a capacity counting unit for counting a predetermined capacity, and a pattern cutting unit. 2. The capacity adjusting device according to claim 1, further comprising a cutting means for cutting.