JPH0494505A - Printed inductor inductance adjustment method - Google Patents

Abstract

PURPOSE:To improve yield and simplify the adjustment process by forming an inductance adjustment conductor pattern with a specified area at the center of the spiral-shaped conductor pattern that constitutes the print inductor and by removing some portion of this pattern to adjust the inductance. CONSTITUTION:When a spiral-shaped conductor pattern 2 that constitutes the printed inductor is formed on a substrate 1, a conductor pattern 4 is placed in the center including an inductance adjustment section 4a. Next, the edge of the section 4a is gradually removed by a laser beam or other means while measuring the inductance and the area is reduced until the inductance reaches a specified value. The area of the section 4a is set in such a way that the inductance will be larger than the specified value when the entire section is removed. As a result, the inductance adjustment process is simplified and the yield can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for adjusting the inductance of a printed inductor formed by printing a spiral conductor pattern on a substrate surface.

(Prior Art) A printed inductor is formed, for example, on the surface of a substrate constituting an oscillator, and forms a resonant circuit together with a capacitor formed between it and a ground pattern on the back surface of the substrate. The resonant frequency of this resonant circuit is adjusted, for example, by adjusting the inductance of the printed inductor.

Conventionally, in order to adjust the inductance of such a printed inductor, for example, as shown in FIG. was. In this way, when the solder 14 is attached to a part of the surface of the conductor pattern 13, the thickness of the conductor pattern 13 in that part becomes thicker, so the printed inductor 1 is adjusted depending on the amount of solder attached and the attached area.
2's inductance becomes smaller. Therefore, the resonant frequency of the resonant circuit is adjusted.

(Problem to be Solved by the Invention) However, when attaching the solder 14 to the surface of the conductor pattern 13 of the printed inductor 12 as described above, the conductor may be The degree of spread of the solder 14 on the surface of the pattern 13 differs, resulting in variations in the amount and area of the solder 14 attached. Therefore, if the amount or area of solder 14 to be adhered is insufficient, the adhesion operation may be repeated until a predetermined amount or area is achieved.

However, if the solder 14 spreads too much and the adhesion area becomes too large, it becomes difficult to correct it.

Therefore, there is a problem in that the inductance adjustment work becomes complicated and the yield decreases unless the operator is skilled.

The present invention has been made in view of the above-mentioned problems, and is an inductance adjustment method for printed inductors that facilitates the inductance adjustment work of printed inductors and that can improve the yield even by non-skilled workers. The purpose is to provide a method.

(Means for Solving the Problem) In order to achieve such an object, in the method for adjusting the inductance of a printed inductor of the present invention, a predetermined area of the spiral conductor pattern forming the printed inductor is The present invention is characterized in that a conductor pattern for inductance adjustment is formed in advance, and at least a portion of this conductor pattern is later removed to change its area, thereby adjusting the inductance of the printed inductor.

(Function) The central part of the spiral conductor pattern that forms the printed inductor is where magnetic flux is concentrated, and if a conductor pattern that does not directly contribute to the formation of the printed inductor is formed here, this conductor pattern will interfere with the magnetic flux created by the printed inductor. Therefore,
A conductor pattern with a predetermined area for inductance adjustment is formed in advance in the center of this spiral conductor pattern, and when at least a part of this conductor pattern is removed later to change its area, the printed inductor is formed. The inductance of the printed inductor can be adjusted by changing the proportion of magnetic flux that is blocked.

(Example) Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

First, a substrate 1 as shown in FIG. 1 is prepared.

This substrate l constitutes, for example, an oscillator, and is made of a dielectric material or the like. On the surface of this substrate 1,
A spiral conductor pattern 3 for forming a printed inductor 2 is printed. One end 3 of this conductor pattern 3
A is connected to an electronic circuit (not shown) constituting an oscillator or the like, and the other end 3b is connected, for example, to a ground pattern formed on the back surface of the substrate 1 via a through hole formed in the substrate 1. A conductor pattern 4 for inductance adjustment having a predetermined area that does not directly contribute to the formation of the printed inductor 2 is formed in the center of the spiral conductor pattern 3 .

This conductor pattern 4 for inductance adjustment obstructs the magnetic flux of the printed inductor 2 formed by the conductor pattern 3 and reduces its inductance. The inductance is set to be larger than a predetermined value.

Next, as shown in FIG. 2, the conductor pattern 4 for inductance adjustment formed in the center of the spiral conductor pattern 3 on the surface of the substrate 1 as described above is subjected to appropriate means such as router, sandblasting, laser beam, etc. For example, the areas are reduced by sequentially removing them from the tip 4a side. In this way, when the conductor pattern 4 for inductance adjustment is removed and its area becomes smaller, the rate at which the magnetic flux of the printed inductor 2 is obstructed decreases. becomes larger. Therefore, while measuring the inductance of the printed inductor 2 and the resonant frequency of the resonant circuit formed by the printed inductor 2, the conductor pattern 4 is removed one by one, and when the inductance or resonant frequency reaches a predetermined value, it is removed. Just stop working. When the conductor pattern 4 is completely removed, the inductance becomes maximum.

The method for adjusting the inductance of a printed inductor according to the present invention has the above-described configuration, but the inductance of the printed inductor is not limited to one that forms a resonant circuit of an oscillator, but can be similarly adjusted for other purposes. . Furthermore, it goes without saying that the shape of the printed inductor is not limited to the rectangular shape shown in the drawings, and even if the printed inductor has other shapes such as a circular shape, the inductance can be similarly adjusted. Also,
The shape of the conductor pattern 4 for inductance adjustment may be determined depending on the Q required for the circuit using the printed inductor 2, the inductance adjustment range, etc.

(Effects of the Invention) As is clear from the above explanation, according to the present invention,
The inductance is adjusted by removing at least a part of the conductor pattern for inductance adjustment having a predetermined area formed in advance in the center of the spiral conductor pattern forming the printed inductor and changing the area. The inductance adjustment work of the printed inductor becomes easier, and the yield can be improved even if the operator is not very skilled.

[Brief explanation of drawings]

1 and 2 are perspective views of a printed inductor for explaining an inductance adjustment method of a printed inductor according to an embodiment of the present invention, and FIG. 3 is a perspective view of a printed inductor for explaining a conventional inductance adjustment method. FIG. l...Substrate, 2...Printed inductor, 3...Conductor pattern forming the printed inductor, 4...Conductor pattern for inductance adjustment.

Claims (1)

[Claims] (1) A method for adjusting the inductance of a printed inductor (2) formed by spirally printing a conductor pattern (3) on the surface of a substrate (1), the method comprising: a spiral conductor pattern (2) forming the printed inductor (2); A conductive pattern (4) with a predetermined area for inductance adjustment is formed in advance in the center of the area 3), and later at least a part of this conductive pattern (4) is removed to change its area, thereby printing. A method for adjusting the inductance of a printed inductor, the method comprising adjusting the inductance of an inductor (2).