JPH07249522A - Inductor device formed of circuit board and its manufacture - Google Patents

Abstract

PURPOSE:To improve the adjusting sensitivity and stability of a function adjusting inductor formed of the microstrip line of a printed wiring board for the high frequency circuit of various kinds of electronic equipment by preventing the deterioration of the adjustment time and yield and the occurrence of cost losses and increasing the inductance of the inductor proportionally to the cut amount of the signal pattern of the printed wiring board. CONSTITUTION:The inductance of an inductor can be increased proportionally to the cut amount of the signal pattern 11, in which a clearance 12 is provided in advance as part of a meandering shape at the central part, of a printed wiring board when the pattern 11 is cut in a meandering state with a laser function trimming device. In addition, when the end section of the pattern 11 is cut off in a straight line, the inductance can be reduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inductor device formed by a circuit board used for a high frequency circuit of electronic equipment and a method for manufacturing the inductor device.

[0002]

2. Description of the Related Art Conventionally, in an inductor device formed by a microstrip line on a circuit board, the inductance is changed by a cutting technique for partially scraping a signal pattern of a copper foil with an ultrasonic cutter or a router.

[0003]

However, in the above-described conventional inductor device formed by the circuit board, the signal pattern is processed because the blade of the cutting machine is brought into contact with the inductor formed by the microstrip line to scrape the signal pattern. It took a lot of time to make adjustments because it was not possible to make measurements at the same time. In addition, since the processing of the signal pattern and the measurement are separated, there is a problem that overtrimming is likely to occur, and the yield is reduced and loss cost is likely to occur.

The present invention solves the above-mentioned conventional problems, and an object of the present invention is to provide an inductor device formed by a circuit board which can be processed and measured at the same time, and a manufacturing method thereof.

[0005]

In order to achieve the above object, the present invention preliminarily provides a part of a signal pattern of an inductor formed by a microstrip line of a printed wiring board with a clearance which is a part of a meandering shape. Laser trimming to form a meandering shape.

[0006]

Therefore, according to the present invention, by cutting the signal pattern of the function adjusting inductor formed in the microstrip line of the printed wiring board in a meandering shape by using the laser function trimming device, the cut amount of the signal pattern can be reduced. Accordingly, the inductance can be proportionally increased, the stability of the function adjustment that simultaneously performs the processing and the measurement is improved, and the adjustment time can be shortened and the yield can be increased.

Further, according to the present invention, the inductance can be reduced by cutting the end face of the signal pattern when overtrimming is performed, so that it is not necessary to discard the printed wiring board and the loss cost can be reduced. You can

[0008]

【Example】

(Embodiment 1) Hereinafter, a first embodiment of the present invention will be described with reference to FIG. FIG. 1A is a plan view of a first layer showing a part of a resonator used in a high frequency circuit formed by a printed wiring board having a four-layer structure, and FIG. 1B is a plan view of a second layer. 1 (c) is a plan view of the third layer, and FIG. 1 (d) is a plan view of the fourth layer. 2 is a sectional view thereof.

1 and 2, 11 is a signal pattern of a function adjusting inductor formed by a microstrip line, a is the width of the signal pattern 11, and 12 is a linear clearance provided in the center of the signal pattern 11. , B
Is the width of the clearance 12, c is the length of the clearance 12, 13 is the signal pattern of the resonator inductor formed of strip lines, 14 is the ground pattern, and 15 is a through hole connecting the signal patterns 11 and 13 with the ground pattern. , 16 are dielectrics, and 17 and 18 are grooves of the signal pattern 11 cut by the laser beam.

The resonator of the high frequency circuit is usually used in combination with a capacitor or an amplifier. In this embodiment, it is assumed that the constant of the function adjusting inductor is changed in order to adjust the oscillation frequency.

The signal pattern 11 of the function adjusting inductor is formed on the first layer of the printed wiring board having a four-layer structure, and the width b of the linear clearance 12 formed at the center thereof is (laser processing width) ≤ b ≦ (limit width of clearance machining of printed wiring board). Also, clearance 1
The length c of 2 is a / 2 <c <a, where a is the width of the signal pattern 11. The signal pattern 11 of the function adjusting inductor includes a clearance 12 and a laser-cut groove 1.
7 and 18 meander in a meandering shape, and the through hole 5 forms the signal pattern 13 of the resonator inductor of the third layer and the ground pattern 1 of the second and fourth layers.
4 are connected in series. The signal pattern 11 of the function adjusting inductor has a microstrip line configuration, and the signal pattern 13 of the resonator inductor has a strip line configuration.

The characteristics of the inductor device formed by the microstrip line of the printed wiring board constructed as described above will be described with reference to FIG. FIG. 3A shows characteristics in the conventional case where no linear clearance is provided in the central portion of the signal pattern 11. As is clear from this figure, in the conventional case where no linear clearance is provided in the central portion of the signal pattern 11, the length of the signal pattern does not increase with a constant inclination according to the cut amount of the signal pattern 11. The change in inductance does not have a perfect proportional relationship with the cut amount, and stable function adjustment cannot be obtained. On the other hand, in the case of the present embodiment, by forming the signal pattern 11 in the order of the grooves 17 and 18 from right to left in FIG. 1, the length of the signal pattern 11 is increased according to the cut amount. Since it increases at a constant inclination and becomes larger than the above, stable function adjustment can be performed with high sensitivity.

(Second Embodiment) Next, a second embodiment of the present invention will be described with reference to FIG. FIG. 4A is a part of a resonator obtained by cutting the signal pattern of the function adjusting inductor of the first layer into a meandering shape by using a laser function trimming device as in the resonator shown in the first embodiment. FIG. 2B is a plan view of a part of the resonator in which the signal pattern of the function adjusting inductor is cut in a meandering shape and then the end face is cut straight.

In FIG. 4, reference numeral 21 is a signal pattern of a function adjusting inductor formed by a microstrip line, 22 is a through hole connecting the signal pattern 21 and a pattern of another layer, 23 is a dielectric, and 24, 25. , 26
Is a groove obtained by cutting the signal pattern 21 in a meandering shape, and 27 is a groove obtained by cutting the end surface of the signal pattern 21 straight.

Recent progress in laser processing technology is 0.53.
By developing a laser function trimming device that outputs laser light having a wavelength of μm, it is possible to process a copper foil pattern formed on a printed wiring board in a non-contact state.

With respect to the signal pattern 21 of the function adjusting inductor shown in FIG. 4, the grooves 24, 25, and 26 are cut in a meandering shape from the end thereof in order, so that excellent characteristics similar to those of FIG. 1 are obtained. The inductance can be increased in proportion to the cut amount.

Further, after the signal pattern 21 is cut in the meandering shape as described above, the end face of the signal pattern 21 is cut straight from top to bottom in the drawing to form the groove 27, so that the cut amount is adjusted according to the cut amount. As a result, the length of the signal pattern 21 is shortened, so that the inductance can be proportionally reduced according to the cut amount of the signal pattern 11, as shown in FIG.

[0018]

As described above, according to the present invention, a signal pattern is formed by using a laser function trimming device by previously providing a clearance which is a part of a meandering shape in a part of a signal pattern of an inductor device formed on a circuit board. The inductance can be increased in proportion to the cut amount when the is cut into a meandering shape, the function adjustment for performing the machining and the measurement at the same time becomes stable, and the adjustment time can be shortened and the high yield can be realized.

According to the present invention, the inductance can be reduced by cutting the end face of the signal pattern when overtrimming the signal pattern of the function adjusting inductor device in a meandering shape. Since it is not necessary to discard the printed wiring board, loss cost can be reduced.

[Brief description of drawings]

FIG. 1A is a plan view of a part of a first layer of a resonator according to a first embodiment of the present invention. FIG. 1B is a part of a second layer of a resonator according to a first embodiment of the present invention. Plan view (c) Plan view of a part of the third layer of the resonator according to the first embodiment of the present invention (d) Plan view of a part of the fourth layer of the resonator according to the first embodiment of the present invention

FIG. 2 is a partial cross-sectional view of a resonator according to the first embodiment.

3A is a characteristic diagram of a function adjusting inductor in the first embodiment; FIG. 3B is a characteristic diagram of a conventional function adjusting inductor in which a clearance is not provided in a signal pattern.

FIG. 4A is a plan view of a part of a resonator in which the signal pattern of the first layer of the function adjusting inductor in the second embodiment of the present invention is cut in a meandering shape; and FIG. 4B, the function adjustment in the same embodiment. View of the straight-cut signal pattern of the first layer of the inductor

FIG. 5 is a characteristic diagram when the signal pattern of the function adjusting inductor in the second embodiment is straight cut.

[Explanation of symbols]

11 Signal Pattern of Function Adjusting Inductor 12 Clearance of Function Adjusting Inductor 13 Signal Pattern of Resonator Inductor 14 Ground Pattern 15 Through Hole 16 Dielectric 17 and 18 Laser Cut Trench 21 Signal Pattern of Function Adjusting Inductor 22 Through hole 23 Dielectric 24, 25, 26 Groove of signal pattern cut in meander shape 27 Straight groove of signal pattern a Signal width of function adjustment inductor b Width of clearance of function adjustment inductor c Length of clearance for function adjusting inductor

Claims (2)

[Claims] 1. An inductor device formed of a circuit board, wherein a clearance which becomes a part of a meandering shape is provided in advance in a part of a signal pattern. 2. The inductance of a signal pattern of an inductor formed by a microstrip line of a printed wiring board is cut in a meandering shape by using a laser function trimming device to increase the inductance and an end surface of the signal pattern when overtrimming is performed. A method for manufacturing an inductor device formed by a circuit board, wherein the inductance is reduced by cutting the inductor.