JP2773651B2 - Multilayer filter - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

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

[0002]

2. Description of the Related Art A laminated filter has a filter main body formed by laminating a plurality of dielectrics, an internal electrode provided at least one between the laminated dielectrics of the filter main body, and an electric electrode connected to the internal electrode. And an external electrode provided on the outer peripheral surface of the filter body.

[0003]

In the above-mentioned conventional configuration,
Since the dielectric and the internal electrode are fired simultaneously, variations in firing conditions, differences in the shrinkage between the dielectric and the internal electrode, variations in the shrinkage between lots, and the like occur. As a result, there is a problem that the resonance frequency and the pass bandwidth are not constant.

An object of the present invention is to solve the above-mentioned problems and to provide a multilayer filter capable of easily adjusting a resonance frequency and a pass bandwidth.

[0005]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides first and second strikes arranged between dielectrics.
The first external electrode side of the lip line electrode is short-circuited, the second
External electrode side as the open end of the part first shield electrode corresponding to the open end or a short circuit portion is to be calculated and removed for a second strip line electrode.

[0006]

According to the present invention, the first external electrode side is a short-circuited end and the second external electrode side is an open end. Since a part of the shield electrode corresponding to the end is deleted over the first and second stripline electrodes, the pass band width of the multilayer filter varies according to the position where the shield electrode is deleted. Thereby, the lamination pass band width can be narrowed without increasing the insertion loss.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A laminated filter according to an embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view of a laminated filter according to an embodiment of the present invention, and FIG. 2 is an exploded perspective view of the laminated filter. 1 and 2, reference numeral 1 denotes a filter main body formed by laminating five dielectrics 2 to 6 shown in FIG. Between these dielectrics 3 and 4, and between dielectrics 4 and 5, two strip line electrodes 71 and 72 for forming a filter , and first input / output electrode 8a,
A second input / output electrode 8b, an additional capacitance electrode 9, and a coupling capacitance electrode 10 are provided. The dielectrics 2 and 3 have the first
A shield electrode 11a is provided, and between the dielectrics 5 and 6
Is provided with a second shield electrode 11b . No.
First and second shield electrodes 11a and 11b and stripper
The ends of the in-electrodes 71 and 72 and the additional capacitance electrode 9 are extended to the outer peripheral surfaces on the front and rear surfaces of the filter main body 1 .
The first external electrode 12a and the second external electrode 12b are electrically connected. In addition, the first and second input / output electrodes 8a,
8b is extended to the outer peripheral surface on the left and right sides of the filter body 1, where the third external electrode 13a and the fourth external electrode 13a are arranged.
It is electrically connected to the electrode 13b . In addition, the first and second
2 strip line electrodes 71 , 72 , first and second input terminals.
Output electrodes 8a, 8b , additional capacitance electrode 9, coupling capacitance electrode 1
0, the first and second shield electrodes 11a and 11b are silver if
And the first to fourth external electrodes 12a, 1
Reference numerals 2b, 13a, and 13b each have a three-layer structure including a lower silver or copper electrode, a middle nickel plating electrode, and an upper solder or tin plating electrode.

Further, first and second strip line power
The poles 71 and 72 are connected to the short-circuit ends 71b and 72b and the open ends 71b.
a and 72a, and the short sides near the first external electrode 12a that are electrically connected are short-circuited ends 71b and 72b .
The sides closer to the external electrode 12b are open ends 71a and 72a.

[0009] The laminated filter configured as described above will be described below with reference to the drawings.

FIG. 3 shows a first shield according to one embodiment.
FIG. 4 is an explanatory view showing a trimming portion of a portion where a part of an electrode 11a is deleted together with a dielectric 2 on an upper surface of a filter main body 1;

With this configuration, the strip line electrode 7
By removing the trimming portion 16 which is a part of the first shield electrode 11a corresponding to the open end 72a from the open end 71a of the first and second 72 through the outermost dielectric 2, the pass band of the multilayer filter is reduced. The width can be reduced.

FIG. 4 is a waveform diagram showing the characteristic frequency of the multilayer filter. As shown in FIG. 4, the transmission characteristic 22 before the trimming adjustment becomes the transmission characteristic 23 after the trimming adjustment,
The pass band width of the multilayer filter can be reduced without increasing the insertion loss.

It should be noted that the trimming portion is the short-circuit end 71b.
Shield electrode 11a corresponding to short-circuit end 72b
A similar effect can be obtained even if a part of the element is removed via the outermost dielectric 2.

In this embodiment, the strip line
Shape shorting end 71b of the down electrodes 71 and 72, 72b by remote open end 71a, although who 72a has a wide area shape, it produces a similar effect in other shapes.

Further, in this embodiment, the strip
First shield electrode 11 corresponding to in-electrodes 71 and 72
a part of a has been deleted along with the dielectric 2 of the outermost layer, strike
Second shield corresponding to lip line electrodes 71 and 72
The same effect is obtained even if a part of the electrode 11b is deleted together with the outermost dielectric 6.

[0016]

As described above, according to the present invention, the dielectric material
Of the first and second strip line electrodes provided in
The external electrode side is a short-circuited end, and the second external electrode side is an open end.
Since a part of the shield electrode corresponding to the short-circuited portion or the open end is removed over the first and second stripline electrodes, the lamination pass bandwidth can be narrowed without increasing insertion loss. is there.

[Brief description of the drawings]

FIG. 1 is a perspective view of a multilayer filter according to an embodiment of the present invention.

FIG. 2 is an exploded perspective view of the multilayer filter.

FIG. 3 is a top view of the multilayer filter.

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

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Filter main body 2 Dielectric 3 Dielectric 4 Dielectric 5 Dielectric 6 Dielectric 8a First input / output electrode 8b Second input / output electrode 11a First shield electrode 11b Second shield electrode 12a First external electrode 12b Second external electrode 13a Third external electrode 13b Fourth external electrode 71, 72 Strip line electrode 71a Open end 71b Short-circuit end 72a Open end 72b Short-circuit end

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hiroshi Shigemura 55-12 Osumi-kohama, Tanabe-cho, Tsuzuki-gun, Kyoto Inside Matsushita Nitto Electric Co., Ltd. (56) References JP-A-4-347903 (JP, A JP-A-3-89601 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) H01P 1/203 H01P 1/205

Claims (2)

(57) [Claims] 1. A filter body formed by laminating a plurality of dielectrics, first and second external electrodes provided on opposite side surfaces of the filter body, and a filter body formed on a side surface of the filter body.
Provided and independently from the first and second external electrodes.
The third and fourth external electrodes that are set up are arranged in parallel between the dielectric and the first external electrode toward the second external electrode, and one end is connected to the first external electrode. Between the first and second stripline electrodes and the lower dielectric of the first and second stripline electrodes, and the third external electrode or the fourth external electrode.
First and second input / output electrodes electrically connected to the electrodes ;
Upper dielectric material of the first and second stripline electrodes
Provided between the first and second external electrodes.
A first shield electrode connected to the first and second input / output ports;
A force electrode is provided between the lower dielectrics, and
1. a second shield electrode connected to a second external electrode;
Wherein the first, short-circuit part each of the first external electrode of the second strip line electrodes, an open end portion of the second outer electrode side, corresponding to the open end the
A laminated filter in which a first shield electrode or a part of the second shield electrode is omitted over the first and second strip line electrodes. 2. A filter body formed by laminating a plurality of dielectrics, first and second external electrodes provided on opposite side surfaces of the filter body, and a filter body formed on a side surface of the filter body.
Provided and independently from the first and second external electrodes.
The third and fourth external electrodes that are set up are arranged in parallel between the dielectric and the first external electrode toward the second external electrode, and one end is connected to the first external electrode. Between the first and second stripline electrodes and the lower dielectric of the first and second stripline electrodes, and the third external electrode or the fourth external electrode.
First and second input / output electrodes electrically connected to the electrodes ;
Upper dielectric material of the first and second stripline electrodes
Between the first and second external electrodes,
A first shield electrode connected to the first and second input terminals;
Provided between the dielectric on the lower side of the output electrode,
First, second shield electrode connected to the second external electrode
With the door, the first, each of the short portion of the first external electrode of the second strip line electrodes, an open end portion of the second outer electrode side, before corresponding to the shorting end
A laminated filter in which the first shield electrode or a part of the second shield electrode is omitted over the first and second stripline electrodes.