JP2734232B2 - LC resonator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an LC resonator used for a filter circuit, an oscillation circuit and the like.

[0002]

2. Description of the Related Art Conventionally, as an LC resonator of this type, a laminated capacitor portion constituted by alternately laminating dielectric layers and capacitor electrode layers, and a magnetic layer and a coil conductor are alternately laminated. In addition, there is known a structure in which each coil conductor is electrically connected to a series via a through-hole or the like and a laminated coil portion configured to be integrally overlapped. In the LC resonator having such a structure, the values of the capacitance C of the multilayer capacitor portion and the inductance L of the multilayer coil portion are apt to vary, and trimming is performed by drilling a hole in the multilayer coil portion to obtain desired resonance characteristics. Needed to be implemented.

An object of the present invention is to provide an LC resonator which can accurately form a capacitance C and an inductance L and does not require trimming for adjusting resonance characteristics.

[0004]

In order to solve the above-mentioned problems, an LC resonator according to the present invention is provided on a surface of a dielectric substrate.
Capacitive electrodes are provided on the back surface, and each of the capacitive electrodes
Extends to opposite end faces of the dielectric substrate,
On at least one of the capacitance electrodes, a resin
A coil conductor is provided via an insulator layer made of the above, and the capacitor electrode and the coil conductor are electrically connected by an external electrode.
It is characterized in that a parallel resonance circuit is formed .

In the above arrangement, since the capacitance electrodes are provided on the front and back surfaces of the dielectric substrate, the dimensional accuracy of the dielectric substrate is improved, and the capacitance electrodes are formed on the dielectric substrate by means of sputtering or photoresist. By providing the capacitor electrode on the front and back surfaces of the body substrate, the dielectric substrate provided with the capacitor electrode becomes a plate-like capacitor with small variation in capacitance C.
Also, setting the dielectric substrate via an insulating layer a conductive coil
Since the structure is provided on the scaled capacitance electrode, it is not necessary to electrically connect a plurality of coil conductors to the series via through holes or the like as in the related art. Therefore, the coil conductor is a thin-film coil having excellent dimensional accuracy, and a coil having a small variation in inductance L is formed.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an LC resonator according to the present invention will be described below with reference to the accompanying drawings. In this embodiment, L
The case of one C resonator will be described, but during mass production, it is manufactured in the form of a mother substrate having a plurality of LC resonators. As shown in FIG. 1 and FIG.
Are provided with capacitance electrodes 2 and 3 respectively. One end of the capacitance electrode 2 extends to the left end surface of the dielectric substrate 1, and one end of the capacitance electrode 3 extends to the right end surface of the dielectric substrate 1. The dimensions, particularly the thickness, of the dielectric substrate 1 are finished with high precision. The capacitance electrodes 2 and 3 are also formed with high dimensional accuracy by using a method such as a sputtering method or a photoresist method, so that variations in the facing area and the like are reduced.

Next, as shown in FIG. 3 and FIG. 4, an insulating layer 5 such as a polyimide resin is formed on substantially the entire surface of the dielectric substrate 1 on which the capacitor electrodes 2 are formed by means such as screen printing. I do. Further, the spiral coil conductor 8, the extraction electrode 9a, and the extraction electrode 9b are respectively provided at the center, left edge, and right edge of the surface of the insulator layer 5 with dimensional accuracy by means such as a sputtering method or a photoresist method. Well formed. to this
Thus, the coil-shaped coil conductor 8 is provided with the insulator layer 5 interposed therebetween.
And provided on the capacitor electrode 2. One end of the coil conductor 8 is electrically connected to the extraction electrode 9a. After the coil conductor 8 and the lead electrodes 9a and 9b are formed, an insulating film 12 such as a polyimide resin is locally provided on the surface of the insulator layer 5 so as to cover a part of the coil conductor 8.
Further, the connecting conductor 1 electrically connecting the other end of the coil conductor 8 and the extraction electrode 9b to the surface of the insulating film 12.
5 is provided.

Next, as shown in FIGS. 5 and 6, the coil conductor 8, the capacitor electrode 3 and the like are covered with insulating layers 17 and 18 made of polyimide resin or the like. At the time of mass production, the mother substrate is thereafter separated for each product. Further, the substrate 1
The external electrodes 20 and 21 are provided on both left and right ends of the device by means such as sputtering to obtain a completed product. The external electrode 20 is electrically connected to the capacitor electrode 2 and the extraction electrode 9a.
1 is electrically connected to the capacitance electrode 3 and the extraction electrode 9b. FIG. 7 is an electrical equivalent circuit diagram of the LC resonator thus obtained. Here, C is a capacitance generated between the capacitance electrodes 2 and 3, and L is an inductance generated in the coil conductor 8. The capacitance C is a capacitance of a plate-shaped capacitor composed of the dielectric substrate 1 having good dimensional accuracy and the capacitance electrodes 2 and 3 having small variations in the facing area and the like.
Further, since the coil conductor 8 does not have a structure in which a plurality of coil conductors are connected in series through a through hole or the like as in the related art, the coil conductor 8 becomes a thin-film coil having excellent dimensional accuracy, and the inductance L varies. Fewer coils are obtained. As a result, an LC resonator that does not require trimming for adjusting resonance characteristics is obtained.

The LC resonator according to the present invention is not limited to the above embodiment, but can be variously modified within the scope of the invention. The coil conductor is an insulator layer on each of the two capacitance electrodes provided on the front and back surfaces of the dielectric substrate.
May be provided. Further, the shapes of the coil conductor and the capacitance electrode are arbitrary and determined according to the specifications of the product.

[0010]

As is clear from the above description, according to the present invention, the dielectric substrate provided with the capacitor electrodes on the front and back surfaces is provided.
Since the coil conductor is provided on the formed capacitor electrode via an insulator layer, a combination of a plate-like capacitor with small variation in capacitance C and a thin-film coil with small variation in inductance L results in resonance. An LC resonator that does not require trimming for adjusting characteristics can be obtained.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a manufacturing procedure of one embodiment of an LC resonator according to the present invention.

FIG. 2 is a vertical sectional view taken along line X-X 'shown in FIG.

FIG. 3 is a perspective view showing a manufacturing procedure of one embodiment of the LC resonator according to the present invention.

FIG. 4 is a vertical sectional view taken along line X-X ′ shown in FIG. 3;

FIG. 5 is a perspective view showing a completed product of one embodiment of the LC resonator according to the present invention.

FIG. 6 is a vertical sectional view taken along the line X-X ′ shown in FIG. 5;

FIG. 7 is an equivalent electric circuit diagram of the LC resonator shown in FIG. 5;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Dielectric substrate 2, 3 ... Capacitance electrode 5 ... Insulator layer 8 ... Conductor for coils 20, 21 ... External electrode

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Takashi Makita 2-26-10 Tenjin, Nagaokakyo-shi, Kyoto Murata Manufacturing Co., Ltd. (56) References JP-A-58-145114 (JP, A) JP-A Sho 62-132309 (JP, A)

Claims (1)

(57) [Claims] A capacitor electrode is provided on each of front and back surfaces of a dielectric substrate.
And one end of each of the capacitor electrodes is provided with the dielectric substrate.
Extending at opposite end faces of the plate, at least
A coil conductor is provided on one of the capacitor electrodes via an insulating layer made of resin , and the capacitor electrode and the coil conductor are electrically connected by external electrodes to form a parallel resonance circuit. An LC resonator characterized in that: