JPS5937569B2 - electronic circuit - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a microelectronic circuit, and more particularly to an electronic circuit in which the value of an inductor formed as a film on a substrate such as a dielectric substrate or an insulating substrate can be easily adjusted. It is something.

Microelectronic circuits are used in a wide range of fields for the purpose of miniaturizing wireless equipment including microportable radios, radio receivers, television receivers, various signal generators, and various signal receivers. , has also been developed. Among these, it is very preferable to form the inductor as a spiral or micro-strip conductive film on the substrate from the viewpoint of miniaturization of the electronic circuit. However, even with an inductor formed as a film, it is necessary to adjust or change the value of the inductor. As this type of technology, Japanese Patent Application Laid-Open No. 51-38062
There is a publication entitled ``Microelectronic circuit''. Japanese Patent Publication No. 51-380
In Publication No. 62, an inductor having a plurality of parallel branches is formed on a part of the base, and the value of the inductor is changed by selectively opening the inductor having these parallel branches with a laser beam. It is configured so that it can be done. However, after making the parallel branch an open circuit, if you want to modify the inductor in that circuit to a smaller value or change it to an inductor that can be applied to a different frequency bandwidth, the parallel branch can be removed. Therefore, it cannot be changed easily. Also, for the resection of parallel branches,
A laser beam is used, but the laser beam is a special device and is not common. However, the purpose of the present invention is to form an inductor as a spiral film on a substrate, and then connect a chip-type capacitor or the like between the spiral wires.
The present invention provides an electronic circuit in which the value of an inductor is variably adjusted by short-circuiting.

Hereinafter, an electronic circuit according to the present invention will be explained based on the drawings.

In FIG. 1, reference numeral 1 denotes a substrate such as a dielectric substrate or an insulating substrate, specifically a ceramic board, a printed wiring board, etc.

A conductor 2 is formed as a film on the base 1 by thick film technology or thin film technology.

The conductor 2 has a pair of terminals 3 and 4, and a portion between the terminals 3 and 4 is formed integrally with a spirally wound portion 5 around the first terminal 3. Note that the number of windings of the winding portion 5 is not limited to that shown in the drawings, but is determined according to the purpose of use or design. This creates a spiral inductor L
is formed. Reference numeral 6 denotes a third terminal, which is formed as a terminal for connecting other parts, separate circuits, etc. as necessary, but is preferably formed as the conductor 2 coating at the same time as the inductor L.

Reference numeral 7 denotes a zipper line, which is also provided as necessary, and electrically connects the first terminal 3 and the third terminal 6.

Next, the case of adjusting the inductor L will be explained.

To adjust the inductor L, a chip type capacitor 8 is used and fixed between adjacent conductors 2 of the winding portion 5 of the inductor L to match the desired inductor value. The capacitor 8 can be fixed in place by applying solder paste to the corresponding surface between each electrode and the conductor 2 of the capacitor 8 and then fixing it using a soldering furnace, or by soldering with a soldering iron (low temperature). There are ways to do this. Therefore, by changing the position of the capacitor 8 fixed between the conductors 2, the length of the conductor 2 between the terminals 3 and 4 can be changed, so the inductor L can be changed as shown in FIG. It can be varied by partially short-circuiting with a capacitor 8. When attaching the capacitor 8, in order to clarify its position, positioning may be performed by resist printing, by marking on a pattern, or by special processing such as forming recesses or protrusions on the base. It is better to use a method such as positioning using In addition, in FIG. 1, terminal 4 and terminal 6
If a capacitor 9 of a chip type, disk type, or trimmer type, which has a much smaller capacitance than the capacitor 8, is provided between the capacitor and the capacitor 8, a resonant circuit as shown in FIG. 3 can be constructed.

Note that it is also possible to use the terminal 3 instead of the terminal 6. As described above, the present invention is configured to short-circuit the conductors of a spiral inductor using a capacitor, so that the inductor value can be easily adjusted.

Also, if you want to change the inductor value for another purpose, for example, change the frequency band from 134 to 150 MHz to 158 to 1
Even when changing to the 74 MHz band, the inductor value can be changed very easily by changing the position of the capacitor. Such an electronic circuit can be used not only as a resonant circuit as described above, but also as a part of a matching circuit of a high frequency circuit.

[Brief explanation of drawings]

FIG. 1 is a diagram showing an embodiment of the present invention, FIG. 2 is a diagram showing adjustment of the inductor L according to the present invention, and FIG. 3 is a diagram showing the case where the inductor L according to the present invention is used as a resonant circuit. It is. In the figure, 1 is a base, 2 is a conductor, 3, 4 and 6 are terminals, and 5
7 is a winding portion, 7 is a zipper wire, and 8 and 9 are capacitors.

Claims (1)

[Scope of Claims] 1. A base comprising a dielectric base or an insulating base, a first terminal and a second terminal on the base, the second terminal being wound around the first terminal. An electronic circuit consisting of an inductor integrally formed of a conductor in a circuit part, and a capacitor provided between adjacent conductors of the inductor so as to change the inductance value by short-circuiting the conductors. . 2. The electronic circuit according to claim 1, wherein the capacitor is a chip type capacitor. 3. The electronic circuit according to claim 1 or 2, wherein another capacitor is provided between the first terminal and the second terminal. 4. In claim 1 or 2, a third terminal provided on the base body, and a jumper provided between the first terminal and the third terminal to short-circuit both terminals. An electronic circuit consisting of wires. 5 In claim 4, the second terminal and the third terminal
An electronic circuit in which another capacitor is installed between the terminals of