JPH1146104A - Dielectric coaxial resonator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the number of resonator component parts and to supply a part that has high reliability at low cost by using an input-output electrode formed on a dielectric for the electric connection between an external circuit and a dielectric coaxial resonator. SOLUTION: A recessed groove 8 is provided from an opening on one end surface 7 of a through hole formed on a cylindrical dielectric 3 in the direction of a mounted surface of the dielectric coaxial resonator 1. An input-output electrode 6 is formed in the groove 8 and a part of the electrode 6 extends up to the mounted surface. A ground electrode 4 is formed on a full surface and four side planes of the other end surface of the dielectric 3. The electrode 4 is formed, separating from the far side of the surface 7 of the four side planes of the dielectric 3. Also, an inner peripheral electrode is formed on an inner peripheral surface of the through hole, its one end is connected to the electrode 6 and the other end is connected to the electrode 4 respectively. As material of the dielectric 3, high dielectric constant ceramic, etc., whose main component is oxide of barium oxide-titanium oxide-oxide of a lanthanoid element is used.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a dielectric filter,
The present invention relates to a structure of a dielectric coaxial resonator used for a high frequency device such as a dielectric duplexer and a voltage controlled oscillator (VCO).

[0002]

2. Description of the Related Art A conventional dielectric coaxial resonator having a structure shown in FIG. 4 is used. As shown in FIG.
The dielectric coaxial resonator 51 has a ground electrode 54 on the outer peripheral surface of the cylindrical dielectric 53 having the through hole 52 except for one end surface 61.
However, an inner peripheral electrode 55 is formed on the inner peripheral surface of the through hole 52. A metal coupling terminal 56 for electrically connecting the inner peripheral electrode 55 and the external circuit 58 is inserted into the through hole 52 from the one end face 61 side. Coupling terminal 56
Is fixed to the inner peripheral electrode 55 by a technique such as soldering. The other end of the coupling terminal 56 is
It is bent so as to be in contact with the external circuit 58 formed on the circuit board 59, and is fixed by solder 57. The ground electrode 54 formed on the outer peripheral surface of the dielectric 53 is connected to the ground electrode 60 formed on the circuit board 59.
Is electrically connected to

[0003]

However, the conventional dielectric coaxial resonator 51 has the following problems.

That is, in the dielectric coaxial resonator 51, it is necessary to attach a coupling terminal 56 for electrically connecting the inner peripheral electrode 55 and the external circuit 58 to the dielectric 53, which is very troublesome. Was. Further, when the dielectric coaxial resonator 51 is mounted on the circuit board 59, it is necessary to bend the coupling terminal 56 in accordance with the difference in height between the through hole 52 and the external circuit 58, and the handling thereof is difficult. Met. Further, the addition of the bending process causes a problem that the reliability of the component is reduced.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a highly reliable dielectric coaxial resonator which is excellent in mountability and is intended to solve the above-mentioned technical problems.

[0006]

In order to achieve the above object, in the dielectric coaxial resonator according to the first aspect of the present invention, a cylindrical dielectric having a through hole and one end face of the dielectric are removed. In the dielectric coaxial resonator having the ground electrode formed on the outer peripheral surface and the inner peripheral electrode formed on the inner periphery of the through hole, the recess extending from the opening on the one end surface side of the through hole to the outer edge of the one end surface. A groove, and an input / output electrode formed on the concave groove, a part of which extends to the mounting surface, and the ground electrode is spaced apart from an edge of one side of each side surface of the dielectric. It is formed.

Further, in the dielectric coaxial resonator according to the second aspect of the present invention, a dielectric having two end faces and four side faces, a through hole formed between the two end faces of the dielectric, An inner peripheral electrode formed on the inner periphery of the through hole, and a ground electrode formed on the outer peripheral surface excluding at least one end surface of the dielectric, and one of four side surfaces of the dielectric is provided. In the dielectric coaxial resonator used by being mounted on a substrate or the like with the mounting surface as the mounting surface, the ground electrodes are formed on the four side surfaces of the dielectric by a predetermined width from the edge on the end face side where the ground electrode is not formed. Not provided, and a concave groove connecting the through-hole and the mounting surface is provided on the end surface where the dielectric ground electrode is not formed, and the input / output is electrically connected to the inner peripheral electrode in the concave groove. Electrodes are formed, and the input and output electrodes are mounted on the dielectric mounting surface. It has been extended to.

Thus, the input / output electrodes and the external circuit can be electrically connected without using the coupling terminals.
Further, by extending the input / output electrodes to the mounting surface, the degree of joining between the input / output electrodes and the external circuit can be further increased. Further, since the ground electrode is formed at a distance from the edge on the one end surface side, the electric field intensity at the input / output electrode can be reduced, and the conductor loss at the input / output electrode can be suppressed.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a dielectric coaxial resonator according to the present invention will be described below with reference to the drawings.

First, the dielectric coaxial resonator 1 is shown in FIGS.
As shown in FIG. 5, a concave groove 8 is provided from the opening in one end face 7 of the through hole 2 formed in the cylindrical dielectric 3 having the through hole 2 in the direction of the mounting surface of the dielectric coaxial resonator 1. I have. The input / output electrode 6 is formed in the concave groove 8, and a part of the input / output electrode 6 extends to the mounting surface. A ground electrode 4 is formed on the entire other end face and four side faces of the dielectric 3. The ground electrode 4 is connected to one end face 7 of the four sides of the dielectric 3.
It is formed at a distance from the side edge. An inner peripheral electrode 5 is formed on the inner peripheral surface of the through hole 2, and one end thereof is connected to the input / output electrode 6 and the other end is connected to the ground electrode 4. In FIGS. 1 and 2, for convenience of description, the mounting surface is illustrated as being the upper surface of the drawing.

As a material of the dielectric 3, a high dielectric constant ceramic or the like containing an oxide of barium oxide-titanium oxide-lanthanide as a main component is used. For the ground electrode 4, the inner peripheral electrode 5, and the input / output electrode 6, a high conductivity material such as silver or copper is used. These electrodes are formed by forming electrodes on the entire surface of the dielectric 3 including the through holes 2 by using a technique such as electroless plating, and then removing unnecessary portions by performing an etching process or the like.

The dielectric coaxial resonator 1 configured as described above is mounted on a circuit board, for example, as shown in FIG. That is, the dielectric coaxial resonator 1 is surface-mounted on the circuit board 12 on which the external circuit 10 and the ground electrode 11 are formed, and the input / output electrodes 6 of the dielectric coaxial resonator 1
The ground electrode 4 is electrically connected to the ground electrode 11 by soldering.

The dielectric coaxial resonator 1 according to the present invention is not limited to the above embodiment, but can be variously modified within the scope of the invention. For example, a dielectric filter, a dielectric duplexer, a VCO, and the like can be configured using a plurality of resonators 1 of the present embodiment. Also,
By removing the electrodes on both end faces of the dielectric coaxial resonator 1, it is possible to use it as a half-wavelength resonator.

[0014]

As is apparent from the above description, the following excellent effects can be obtained according to the dielectric coaxial resonator of the present invention.

First, the resonator is constructed by using an input / output electrode formed on a dielectric without using an externally connected terminal for electrical connection between the external circuit and the dielectric coaxial resonator. The number of components to be manufactured can be reduced, and highly reliable components can be supplied at low cost. Also,
Since the resonator can be reduced in size without using the coupling terminal, it is possible to reduce the size of the entire circuit as a result.

Furthermore, by extending a part of the input / output electrode to the mounting surface, the degree of joining between the input / output electrode and the external circuit is increased, and the electrical conduction can be performed more reliably. Furthermore, since the input / output electrode / ground electrode of the resonator and the mounting surface of the circuit board can all be located on the same plane, the stability of the resonator at the time of mounting can be improved.

In addition, the ground electrodes formed on the four sides of the dielectric coaxial resonator are formed at a distance from the edge on the side of the end face where the groove is formed, so that the ground electrodes are formed in the groove. The electric field strength of the input / output electrode portion can be reduced. As a result, conductor loss in the input / output electrode portion can be suppressed. This also allows the miniaturization of the resonator. That is, when the same no-load Q is realized, a material having a high dielectric constant can be used as the dielectric material because the conductor loss can be suppressed, so that the size of the resonator can be reduced. is there.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a dielectric coaxial resonator according to the present invention.

FIG. 2 is a cross-sectional view taken along line XX of FIG.

FIG. 3 is a cross-sectional view showing a mounted state of the dielectric coaxial resonator of the present invention.

FIG. 4 is a cross-sectional view showing a mounted state of a conventional dielectric coaxial resonator.

[Explanation of symbols]

 1, 51 ... dielectric coaxial resonator 2, 52 ... through hole 3, 53 ... dielectric 4, 54 ... ground electrode 5, 55 ... inner peripheral electrode 6 ... input / output Electrodes 7, 61 ... One end face 8 ... Grooves 9, 57 ... Solder 10, 58 ... External circuit 11, 60 ... Ground electrode 12, 59 ... Circuit board 56 ... Coupling terminal

Claims (2)

[Claims] 1. A cylindrical dielectric having a through hole, a ground electrode formed on an outer peripheral surface excluding one end surface of the dielectric, and an inner peripheral electrode formed on an inner periphery of the through hole. In the dielectric coaxial resonator, a concave groove extending from the opening on the one end surface side of the through hole to the outer edge of the one end surface, and an input / output electrode formed on the concave groove and a part of which extends to the mounting surface. A dielectric coaxial resonator having a ground electrode formed at a distance from an edge of one side of each side surface of the dielectric. 2. A dielectric having two end faces and four side faces, a through hole formed between the two end faces of the dielectric, an inner electrode formed on an inner periphery of the through hole, and a dielectric. And a ground electrode formed on the outer peripheral surface excluding at least one end surface of the dielectric material. The dielectric coaxial resonance device is mounted on a substrate or the like using one of the four side surfaces of the dielectric as a mounting surface. Wherein the ground electrode is not formed on the four side surfaces of the dielectric by a predetermined width from the edge on the side of the end face where the ground electrode is not formed; and that the ground electrode of the dielectric is formed. Not on the end face,
A concave groove connecting the through hole and the mounting surface is provided, an input / output electrode electrically connected to the inner peripheral electrode is formed in the concave groove, and the input / output electrode extends to the dielectric mounting surface. A dielectric coaxial resonator characterized in that: