JPH088608A - Filter - Google Patents

Abstract

PURPOSE:To provide a filter which can omit an external capacitor for adjustment of frequency and also can be adjusted even after its mounting. CONSTITUTION:The electrodes 2-4 are provided on a substrate 1, and the input electrodes are placed on the mounting surface of the resonators 6-8 against the substrate 1 with the prescribed spaces secured to the outer circumferential electrodes provided on the mounting surface. Then the electrodes 2-4 of the substrate 1 are connected to the input electrodes of the resonators 6-8. Meanwhile an opening part 15 is formed on the substrate 1 so that the input electrodes of the resonators 6-8 or the outer circumferntial electrodes placed opposite to these input electrodes can be viewed from the rear side of the substrate 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a filter using a dielectric resonator.

[0002]

2. Description of the Related Art Conventionally, in this type of filter, a dielectric resonator is mounted on a substrate, and an input electrode of this substrate and an input electrode of the dielectric resonator are connected via a capacitor to form a notch filter. Was.

[0003]

In the above structure, when adjusting the notch frequency, it is necessary to replace the capacitor with one having a capacitance value corresponding to it.
Therefore, many types of capacitors are required, and
There was a problem that it became difficult to make fine adjustments after mounting. Therefore, the present invention, without using an external capacitor,
Moreover, the purpose is to enable adjustment after mounting.

[0004]

In order to achieve this object, the present invention provides a mounting surface of the resonator on a substrate,
The input electrode is arranged at a predetermined distance from the outer peripheral electrode provided on the mounting surface thereof, and the input electrode of the substrate and the input electrode of the dielectric resonator are connected to each other, and on the substrate, An opening is formed so that the input electrode of the dielectric resonator or the outer peripheral electrode facing the input electrode faces the back surface of the substrate.

[0005]

With the above structure, after mounting the dielectric resonator on the substrate, the input electrode of the dielectric resonator or the outer peripheral electrode facing the dielectric resonator can be removed from the back side of the substrate through the opening. Since it is possible to change the capacitance value of the capacitor formed between the two, it is possible to adjust the frequency that becomes the notch without providing an externally attached capacitor.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In FIG. 1, reference numeral 1 is a substrate formed of a material having a low dielectric constant, and electrodes 2, 3, 4, 5 are provided on one end side of the surface side thereof as shown in FIG. Moreover, three dielectric resonators 6, 7, and 8 are mounted in parallel on the substrate 1. These dielectric resonators 6 to 8 are prismatic as shown in FIG. 6, and a through hole 9 is provided in the central portion thereof. An electrode 10 is provided in the through hole 9 and on the outer peripheral surface and the lower surface in FIG. Further, a linear input electrode 11 is provided on the mounting surface portion of the dielectric resonators 6 to 8 on the substrate 1, and the outer peripheral electrode 10 on one end side of the input / output electrode 11 is as shown in FIG. , It becomes concave like it is wrapped. These dielectric resonators 6 to
8 is mounted on the substrate 1 shown in FIG. 7 as shown in FIG. By this mounting, the input electrode 11 of the dielectric resonator 6 becomes the substrate 1
The electrodes 2 and 11 of 7 are soldered to 3 and 11 of 8 is soldered to 4, respectively, and are also electrically connected. Although not shown only in FIG. 5 on the other end of the surface of the substrate 1, metal foils 12, 13 and 14 for fixing are provided, and 6 is attached to 12 by means of solder.
7 is fixed to 3 and 8 is fixed to 14. In this embodiment, an opening 15 is provided in the center of the substrate 1 as shown in FIG. 5, and the opening 15 allows the input electrode 11 of the dielectric resonators 6 to 8 from the back surface side as shown in FIG.
And, the outer peripheral electrodes 10 facing each other can be exposed at one end side thereof. Therefore, if the input electrode 11 or the outer peripheral electrode 10 facing the input electrode 11 is cut through the opening 15, the capacitance value of the capacitor 16 shown in FIG. 4 formed between the two can be varied. The inductors 17 and 18 in FIG. 4 are mounted between the electrodes 2, 3 and 3, 4 as shown in FIG. 5, and the capacitors 19, 20 and 21 in FIG.
It is mounted between 5 and 3,5 and 4,5, thereby forming a notch filter as shown in FIG.
The opening 15 is extended to the outside of the three dielectric resonators 6, 7 and 8 as shown in FIG. 3, so that the outer peripheral electrodes 10 at both ends are scraped off as shown in FIG. Will be able to. FIG. 8 shows another embodiment. In this embodiment, the open end has a concave shape and an electrode is provided inside the dielectric resonator, which is shown in FIG. As described above, three may be mounted side by side.

[0007]

As described above, according to the present invention, an input electrode is arranged on the mounting surface of the resonance substrate on the substrate at a predetermined distance from the outer peripheral electrode provided on the mounting surface, and the input of the substrate is suppressed. Connecting the electrode for input and the input electrode of the dielectric resonator,
On the substrate, an input electrode of the dielectric resonator or an outer peripheral electrode facing the input electrode is formed with an opening so as to face from the back surface of the substrate.

With the above arrangement, after the dielectric resonator is mounted on the substrate, the input electrode of the dielectric resonator or the outer peripheral electrode facing the dielectric resonator is scraped from the rear surface side of the substrate through the opening. For example, since the capacitance value of the capacitor formed between the two can be changed, the notch frequency can be adjusted without separately providing an external capacitor.

[Brief description of drawings]

FIG. 1 is a perspective view of an embodiment of the present invention.

[Figure 2] Plan view

[Figure 3] Rear view

FIG. 4 is an electrically equivalent circuit diagram thereof.

FIG. 5 is an exploded perspective view thereof.

FIG. 6 is a perspective view of the dielectric resonator.

FIG. 7 is a perspective view of the substrate.

FIG. 8 is a perspective view of a dielectric resonator according to another embodiment of the present invention.

[Explanation of symbols]

 1 Substrate 2 Electrode 3 Electrode 4 Electrode 6 Dielectric Resonator 7 Dielectric Resonator 8 Dielectric Resonator 10 Peripheral Electrode 11 Input Electrode 15 Opening

Claims (4)

[Claims] 1. A substrate and a dielectric resonator mounted on the surface of the substrate, wherein an input electrode is provided on the substrate, and an input electrode is provided on a mounting surface of the resonator on the substrate. The electrodes are arranged at a predetermined distance from the outer peripheral electrodes provided on the mounting surface of the electrodes to connect the input electrodes of the substrate and the input electrodes of the dielectric resonator, and the substrate is provided with the dielectric material. A filter in which an opening is formed so that the input electrode of the resonator or the outer peripheral electrode facing the input electrode is faced from the back surface of the substrate. 2. The filter according to claim 1, wherein a plurality of dielectric resonators are arranged in parallel on a substrate and mounted, and input electrodes of adjacent dielectric resonators are connected by an inductance. 3. The filter according to claim 1, wherein the input electrode of the dielectric resonator has a linear shape, and the outer peripheral electrode has a concave shape so as to wrap one end side of the input electrode. 4. The filter according to claim 1, wherein the opening extends to the outside of the dielectric resonator.