JPH0878909A - Laminated filter - Google Patents

Abstract

PURPOSE: To provide the laminated filter with which the notch of a frequency on the high band side can be easily controlled and yield can be improved. CONSTITUTION: An electrode 16 for controlling the notch of the frequency on the high band side is provided on the upper surface of a main body 15 of this filter, and an electric connecting part 17 for electrically connecting an external electrode and the electrode 16 for notch control is provided. Besides, the area of the electrode 16 for notch control is enlarged rather than the area of the electric connecting part 17, and the shape of that electric connecting part 17 is formed into a thin linear shape.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laminated filter used for communication equipment and the like.

[0002]

2. Description of the Related Art A conventional technique will be described below with reference to the drawings.

FIG. 5 is an exploded perspective view of a conventional laminated filter, and FIG. 6 is a perspective view of the same laminated filter.

As shown in FIGS. 5 and 6, the laminated filter has ceramic sheets 1, 3 made of a plurality of dielectrics.
The filter main body 15 is formed by laminating 5, 9, and 11. The lower shield electrode 2 is attached to the ceramic sheet 1,
The ceramic sheet 3 includes internal electrodes 6 for interstage coupling, electrodes 7 for input / output coupling, and electrodes 8 for frequency adjustment.
The ceramic sheet 5 is provided with the strip line 4, and the ceramic sheet 9 is provided with the upper shield electrode 10. Also, the lower shield electrode 2 and the upper shield electrode 1
0, the strip line 4, and the frequency adjusting electrode 8 are electrically connected to the earth electrodes 12 and 14 which are external electrodes provided on the outer peripheral surface of the filter body 15. Further, the input / output coupling electrode 7, the lower shield electrode 2, the upper shield electrode 1
0 is electrically connected to the input / output electrode 13 which is an external electrode provided on the outer peripheral surface of the filter body 15.

[0005]

In the above structure, the strip line 4, the interstage coupling electrode 6, the input / output coupling electrode 7 and the frequency adjusting electrode 8 provided on the ceramic sheets 3 and 5 inside the filter body 15 are provided. When they were respectively formed, some printing deviations occurred and the frequency characteristics were slightly different depending on the individual laminated filters. Moreover, when adjusting these frequency characteristics, since the notch on the high frequency side of the frequency could not be adjusted, there was a problem that the frequency characteristics could not be adjusted completely, leading to a decrease in yield. Was there.

In order to solve the above problems, it is an object of the present invention to provide a laminated filter in which the notch on the high frequency side can be easily adjusted and the yield can be improved.

[0007]

In order to achieve the above object, in a laminated filter of the present invention, a filter body formed by laminating a plurality of dielectrics is provided, and a filter body is provided between the laminated dielectrics of the filter body. A strip line and an internal electrode, and an external electrode that is electrically connected to the strip line and the internal electrode and is provided on the outer peripheral surface of the filter body. A notch adjusting electrode is provided, and an electrical connecting portion that electrically connects the external electrode electrically connecting to the internal electrode and the notch adjusting electrode is provided.

[0008]

With the above configuration, if a part of the notch adjusting electrode provided on the upper surface of the filter body is removed, the high frequency side can be easily adjusted, and the frequency characteristic is completely adjusted. The yield can be improved.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is an exploded perspective view of a laminated filter in the first embodiment of the present invention, FIG. 2 is a perspective view of the laminated filter, and FIG. 3 is an equivalent circuit diagram of the laminated filter.

The same components as those in the conventional example are designated by the same reference numerals. As shown in FIGS. 1 and 2, the laminated filter is a ceramic sheet made of a plurality of dielectrics 1, 3, 3.
The filter main body 15 is formed by laminating 5, 9, and 11. The lower shield electrode 2 is attached to the ceramic sheet 1,
The ceramic sheet 3 includes internal electrodes 6 for interstage coupling, electrodes 7 for input / output coupling, and electrodes 8 for frequency adjustment.
The ceramic sheet 5 is provided with the strip line 4, and the ceramic sheet 9 is provided with the upper shield electrode 10. Also, the lower shield electrode 2 and the upper shield electrode 1
0, the strip line 4, and the frequency adjusting electrode 8 are electrically connected to the earth electrodes 12 and 14 which are external electrodes provided on the outer peripheral surface of the filter body 15. Further, the input / output coupling electrode 7, the lower shield electrode 2, the upper shield electrode 1
0 is electrically connected to the input / output electrode 13 which is an external electrode provided on the outer peripheral surface of the filter body 15. The notch adjusting electrode 16 on the high frequency side is provided on the upper surface of the filter body 15, and the electrical connecting portion 17 that electrically connects the external electrode and the notch adjusting electrode 16 is provided. Further, the area of the notch adjusting electrode 16 is larger than the area of the electrical connecting portion 17, and the electrical connecting portion 1
The shape of 7 is a thin linear shape.

Further, the equivalent circuit diagram at that time is as shown in FIG. 3, and the notch adjusting circuit 18 for adjusting the notch by the notch adjusting electrode 16 and the electrical connecting portion 17,
19 is formed.

The operation will be described below with reference to the drawings. As shown in FIG. 4, X is a characteristic frequency waveform diagram before frequency adjustment, and Y is a characteristic frequency waveform diagram after frequency adjustment. As shown in the drawing, when the frequency of the high frequency side of the laminated filter is adjusted, the high frequency side of the frequency can be easily adjusted by removing a part of the notch adjusting electrode 17 provided on the upper surface of the filter body 15. Therefore, the frequency characteristics are completely adjusted, and the yield can be improved.

Further, the area of the notch adjusting electrode 16 is larger than the area of the electric connecting portion 17, and since the electric connecting portion 17 has a thin linear shape, the inductance in the electric connecting portion 17 is small. Are efficiently formed.

[0015]

As described above, according to the present invention, by removing a part of the notch adjusting electrode provided on the upper surface of the filter body, the high frequency side can be easily adjusted, and the frequency characteristics can be adjusted. It is possible to provide a laminated filter in which the adjustment is completely performed and the yield is improved.

Further, since the area of the notch adjusting electrode is larger than the area of the electrical connecting portion and the shape of the electrical connecting portion is a thin linear shape, the inductance is efficiently formed in the electrical connecting portion. To be done.

[Brief description of drawings]

FIG. 1 is an exploded perspective view of a laminated filter according to the present invention.

FIG. 2 is a perspective view of the laminated filter.

FIG. 3 is an equivalent circuit diagram of the multilayer filter.

FIG. 4 is a characteristic frequency waveform diagram of the multilayer filter.

FIG. 5 is an exploded perspective view of a conventional laminated filter

FIG. 6 is a perspective view of the laminated filter.

[Explanation of symbols]

 1, 3, 5, 9, 11 Ceramic sheet 2 Lower shield electrode 4 Stripline 6 Inter-stage coupling electrode 7 Input / output coupling electrode 8 Frequency adjusting electrode 10 Upper shield electrode 12, 14 Earth electrode 13 Input / output electrode 15 Filter body 16 Notch adjustment electrode 17 Electrical connection 18 Notch adjustment circuit 19 Notch adjustment circuit

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tadanori Fujisawa 55-12, Ozumi, Osamu, Tanabe-cho, Tsuzuki-gun, Kyoto Prefecture Matsushita Nitto Electric Co., Ltd.

Claims (3)

[Claims] 1. A filter body formed by laminating a plurality of dielectrics, a strip line and an internal electrode provided between the laminated dielectrics of the filter body, and an electrical connection between the strip line and the internal electrode. And an external electrode provided on the outer peripheral surface of the filter body while being connected to, the notch adjusting electrode on the high frequency side is provided on the upper surface of the filter body, and the external electrode and the notch adjusting electrode. A laminated filter provided with an electric connection portion for electrically connecting. 2. The laminated filter according to claim 1, wherein the area of the notch adjusting electrode is larger than the area of the electrical connection portion. 3. The laminated filter according to claim 1, wherein the electric connection portion has a thin linear shape.