JP2806682B2 - Multilayer dielectric 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 dielectric filter, and more particularly to a high-frequency circuit filter used for high-frequency circuit radio equipment such as a portable telephone and a laminated dielectric filter used for an antenna duplexer.

[0002]

2. Description of the Related Art FIG.
6 and 37 are a schematic development view and a perspective view, respectively, of the laminated dielectric filter devised by the present inventors. In this multilayer dielectric filter, as shown in FIG. 36, first, one end is formed on the surface of the dielectric layer 11 by a ground electrode 7 described later.
Resonating elements 21 to 23 each formed of a quarter-wavelength stripline resonator electrically connected to the first electrode are formed at predetermined intervals, and one end is electrically connected to the ground electrode 70 and the other end is connected to the ground electrode 70. Electrodes 31 to 33, which are separated from the open ends of the resonance elements 21 to 23 by a predetermined distance and face the resonance elements 21 to 23, respectively, are formed on the surface of the dielectric layer 11 to inductively couple the respective resonance elements 21 to 23. Then, the input electrode 41 overlapping the part of the resonance element 21 on the input side with the dielectric layer 12 interposed therebetween is formed on the surface of the dielectric layer 12 laminated on the dielectric layer 11.
An output electrode 42 is formed so as to overlap a part of the output-side resonance element 23 with the dielectric layer 12 interposed therebetween, and the dielectric layer 13 is laminated on the dielectric layer 12 to form a laminated dielectric filter body. .

Next, as shown in FIG. 37, a ground electrode 70 is formed on the front and back surfaces of the multilayer dielectric filter main body, and on the side surfaces excluding the input terminal portion 61 and the output terminal portion 62.
An input terminal 51 which is electrically insulated from a ground electrode 70 and is electrically connected to an input electrode 41 in an input terminal portion 61 formed on a side surface of the multilayer dielectric filter body; An output terminal 52 electrically insulated from the ground electrode 70 and electrically connected to the output electrode 42 is formed in an output terminal portion 62 formed on a side surface of the filter body.

An electrical equivalent circuit of the laminated dielectric filter shown in FIGS. 36 and 37 is as shown in FIG. FIG.
8, reference numeral 111 denotes a resonance element 21 and an input electrode 41.
Reference numeral 112 denotes a capacitance between the resonance element 23 and the output electrode 42, and reference numerals 121 to 123 denote capacitances between the resonance element 21 and the electrode 31, and a capacitance between the resonance element 22 and the electrode 31, respectively. 32, the resonance element 23 and the electrode 3
3, reference numeral 131 denotes an inductance indicating inductive coupling between the resonance element 21 and the resonance element 22, and reference numeral 132 denotes an inductance indicating inductive coupling between the resonance element 22 and the resonance element 23. And constitute a bandpass filter. Note that the capacitances 211, 221, 231 and the inductance 212 of the parallel resonance circuit,
222 and 232 are capacitance and inductance when the resonance elements 21, 22, and 23 are equivalently converted, respectively.

In such a laminated dielectric filter, the distributed coupling between the resonance elements 21 to 23 causes
A band-pass filter having a desired frequency characteristic such as a bandwidth is obtained. However, in such a configuration, since there is only coupling between adjacent resonance elements 21 to 23, an attenuation peak is formed to reduce the attenuation characteristic. Could not improve. In order to improve the attenuation characteristics, a method of increasing the number of resonance elements may be adopted. However, when the number of resonance elements is increased, there is a problem that insertion loss increases.

Therefore, in order to form an attenuation peak in the frequency characteristic, it has been sought to provide a coupling that jumps over the resonance elements in addition to between adjacent resonance elements. For example, as disclosed in Japanese Patent Application Laid-Open No. 64-78001, it has been proposed to form an attenuation peak on a high frequency side or a low frequency side of a band by coupling separated resonance elements.

However, such a method requires a coil for coupling between the resonance elements, a capacitance element for coupling a separate resonance element, and the like, in addition to the resonance elements, and the production is troublesome. In addition to the problem that the frequency of the attenuation peak varies greatly, there is also a problem that the number of components increases and miniaturization becomes difficult.

In addition, such a band-pass filter is
The bandwidth is not sufficient for use as a high-frequency circuit filter for a portable telephone terminal or a filter for an antenna duplexer. 36 and 37, there has been no method other than to strengthen the coupling between the resonance elements by bringing adjacent resonance elements extremely close to each other to widen the band width of the laminated dielectric filter shown in FIGS. However, when the resonance elements are brought close to each other in this manner, the resonance element characteristics become extremely sensitive to manufacturing variations (for example, printing variations) and the like, and a band-pass filter having constant characteristics is stably supplied. Was difficult.

[0009] Further, in portable telephone terminals, there is an increasing demand for miniaturization, and along with this, it is also strongly demanded that bandpass filters used therein be miniaturized. In a laminated dielectric filter having a structure, there is a limit to the size reduction.

Accordingly, it is an object of the present invention to provide a laminated dielectric filter which forms an attenuation peak to improve the attenuation characteristics, has a small variation in the frequency of the attenuation peak, and is easily miniaturized. is there.

It is another object of the present invention to provide a laminated dielectric filter in which the coupling between the resonance elements is strengthened without bringing the resonance elements extremely close to each other and the band is broadened.

It is still another object of the present invention to provide a more compact laminated dielectric filter.

[0013]

According to the present invention, an input end side resonance element, an output end side resonance element, a first main surface of the input end side resonance element and a first main surface of the output end side resonance element are provided. A first ground electrode opposed to the main surface of the first end element and provided with a first dielectric layer interposed between the input end side resonance element and the output end side resonance element; And a first dielectric layer between the input terminal side resonance element and the first dielectric layer between the output terminal side resonance element and the first ground electrode.
A first internal ground electrode provided so as to face a part of the main surface of the first element and a part of the first main surface of the output terminal side resonance element; and the input end side resonance element and the output end side resonance element. An input provided in the first dielectric layer between the element and the first ground electrode so as to face a part of the input end side resonance element and a part of the output end side resonance element. And a first laminated dielectric filter having at least one of the electrode and the output electrode.

In the first multilayer dielectric filter, preferably, a second main surface of the input end side resonance element opposite to the first main surface and the second main surface of the output end side resonance element are provided. A second main surface opposite to the first main surface and provided between the input-end resonance element and the output-end resonance element with a second dielectric layer interposed therebetween; A second multilayer dielectric filter further having a ground electrode can be obtained.

In the second laminated dielectric filter, preferably, the second laminated dielectric filter is provided between the input-side resonance element and the output-side resonance element and the second ground electrode.
A second part of the dielectric layer, which is provided so as to face a part of the second main surface of the input end side resonance element and a part of the second main surface of the output end side resonance element. A third laminated dielectric filter further having an internal ground electrode can be obtained.

In the first multilayer dielectric filter, preferably, a part of a second main surface of the input end side resonance element opposite to the first main surface is connected to the output end side resonance element. A second dielectric layer opposed to a part of a second main surface opposite to the first main surface of the element and between the input-end resonance element and the output-end resonance element; A fourth laminated dielectric filter further having the other of the input electrode and the output electrode provided therebetween can be obtained.

In the second or third laminated dielectric filter, preferably, the second dielectric between the input-side resonance element and the output-side resonance element and the second ground electrode. An input electrode or an output electrode provided in a layer so as to face a part of the second main surface of the input end side resonance element and a part of the second main surface of the output end side resonance element; Can be obtained.

In any one of the first to fifth laminated dielectric filters, preferably, one end of the input end side resonance element and one end of the output end side resonance element are the first end.
And the first internal ground electrode is connected to the input terminal at the open end, which is the other end of the input end resonance element, and at the open end, which is the other end of the output end resonance element. Obtaining a sixth laminated dielectric filter provided so as to face a part of the first main surface of the end-side resonance element and a part of the first main surface of the output-end resonance element. Can be.

In any one of the second, third and fifth laminated dielectric filters, preferably, one end of the input end side resonance element and one end of the output end side resonance element are connected to the first ground electrode. The first and second internal ground electrodes are electrically connected to the open end side, which is the other end of the input end side resonance element, and the open end side, which is the other end of the output end side resonance element, Preferably, a seventh element is provided opposite to a part of the first and second main surfaces of the input terminal side resonance element and the output terminal side resonance element.
Can be obtained.

Further, according to the present invention, an input-end-side resonance element, an output-end-side resonance element, and one or more internal components arranged in parallel between the input-end-side resonance element and the output-end-side resonance element. A resonance element, a first main surface of the input terminal side resonance element, a first main surface of the output terminal side resonance element, and a first main surface of the internal resonance element; A first ground electrode provided with a first dielectric layer interposed between the output-end-side resonance element and the internal resonance element, the input-end-side resonance element, the output-end-side resonance element, In the first dielectric layer between the internal resonance element and the first ground electrode, a part of the first main surface of the input end side resonance element, the first main surface of the output end side resonance element, 1 and a first surface provided opposite to a part of the first main surface of the internal resonance element. A first ground electrode, the input end side resonance element, the output end side resonance element, and the input end side resonance element in the first dielectric layer between the internal resonance element and the first earth electrode. Alternatively, a part of any one of the output-end-side resonance elements and a part of the internal resonance element closest to the input-end-side resonance element or the output-end-side resonance element are provided. An eighth laminated dielectric filter having either the input electrode or the output electrode thus obtained can be obtained.

In the eighth laminated dielectric filter, preferably, a second main surface of the input end side resonance element opposite to the first main surface, and a second main surface of the output end side resonance element. 1, a second main surface opposite to the first main surface and a second main surface of the internal resonance element opposite to the first main surface, and the input end side resonance element and the output end A ninth laminated dielectric filter further having a second ground electrode provided between the side resonance element and the internal resonance element with a second dielectric layer interposed therebetween can be obtained.

In the ninth multilayer dielectric filter, preferably, the second resonance element between the input terminal side resonance element, the output terminal side resonance element and the internal resonance element and the second ground electrode. In the dielectric layer, a part of the second main surface of the input end side resonance element, a part of the second main surface of the output end side resonance element, and the second main surface of the internal resonance element are provided. A tenth laminated dielectric filter further having a second internal ground electrode provided so as to face a part of the surface can be obtained.

In the eighth laminated dielectric filter, it is preferable that the other one of the input-end-side resonance element and the output-end-side resonance element be the second main body on the side opposite to the first main surface. A second surface opposite to the first main surface of the internal resonance element closest to a part of the surface and the other one of the input end side resonance element or the output end side resonance element;
Opposing a part of the main surface of the input terminal side resonance element or the output end side resonance element and the other one of the input end side resonance element or the output end side resonance element. A second between the nearest internal resonance element
An eleventh laminated dielectric filter further having the other of the input electrode and the output electrode provided with the dielectric layer interposed therebetween can be obtained.

In the ninth or tenth laminated dielectric filter, preferably, the input end side resonance element, the output end side resonance element, the internal resonance element, and the second
A part of the other one of the input-end-side resonance element and the output-end-side resonance element and the input-end-side resonance element or the output-end-side resonance A twelfth laminated dielectric filter can further be provided that further includes the other of the input electrode or the output electrode provided to face a part of the internal resonance element closest to the other of the elements.

In any one of the eighth to twelfth laminated dielectric filters, preferably, one end of the input end side resonance element, one end of the output end side resonance element, and one end of the internal resonance element are connected to the second end. The first internal ground electrode is electrically connected to the first end ground electrode, and the first internal ground electrode is the open end side which is the other end of the input end side resonance element, the open end side which is the other end of the output end side resonance element, and A part of the first main surface of the input-end-side resonance element, a part of the first main surface of the output-end-side resonance element, and the internal resonance element on the open end side that is the other end of the internal resonance element A thirteenth laminated dielectric filter provided to face a part of the first main surface can be obtained.

In any one of the ninth, tenth, and twelfth laminated dielectric filters, preferably, one end of the input-end resonance element, one end of the output-end resonance element, and one end of the internal resonance element Are electrically connected to the first ground electrode, and the first and second internal ground electrodes are connected to an open end which is the other end of the input end side resonance element, and the other end of the output end side resonance element. On the open end side and the open end side which is the other end of the internal resonance element,
Obtaining a fourteenth laminated dielectric filter provided to face each of the first and second main surfaces of the input end side resonance element, the output end side resonance element, and the internal resonance element. Can be.

Further, according to the present invention, an input end side resonance element, an output end side resonance element, a first main surface of the input end side resonance element, and a first main surface of the output end side resonance element. A first ground electrode provided between the input end side resonance element and the output end side resonance element with a first dielectric layer interposed therebetween; and the input end side resonance element and the output end A part of the first main surface of the input end side resonance element and a portion of the first end surface of the output end side resonance element in the first dielectric layer between the side resonance element and the first ground electrode. A first internal ground electrode provided to face a part of the first main surface, a part of a second main surface opposite to the first main surface of the input end side resonance element, The output end side resonance element is opposed to a part of a second main surface opposite to the first main surface, and the input end side resonance element and One and one of the second dielectric layer interposed therebetween provided an input electrode or the output electrode between the serial output end side resonance element, it is possible to obtain the first 15 laminated dielectric filter having a.

In the fifteenth laminated dielectric filter, preferably, one end of the input-end-side resonance element and one end of the output-end-side resonance element are electrically connected to the first ground electrode. The internal ground electrode of the first main surface of the input end side resonance element at the open end side which is the other end of the input end side resonance element and the open end side which is the other end of the output end side resonance element. A first part provided to face a part and a part of the first main surface of the output end side resonance element;
6 can be obtained.

Still further, according to the present invention, at least one of an input end side resonance element, an output end side resonance element, and one or more parallel arrangements between the input end side resonance element and the output end side resonance element are provided. An internal resonance element, a first main surface of the input end side resonance element, a first main surface of the output end side resonance element, and a first main surface of the internal resonance element; A first element between the element, the output end side resonance element and the internal resonance element.
A first ground electrode provided between the first ground electrode and the first ground electrode between the input end side resonance element, the output end side resonance element, the internal resonance element, and the first ground electrode.
A part of the first main surface of the input end side resonance element, a part of the first main surface of the output end side resonance element, and the first main surface of the internal resonance element. A first internal ground electrode provided so as to face a part of the main surface, and a first internal ground electrode opposite to the first main surface of one of the input end side resonance element and the output end side resonance element. 2 and a second main surface of the internal resonance element which is closest to the input terminal side resonance element or the output terminal side resonance element and which is closest to the first main surface of the internal resonance element. A part of the surface, and the one closest to the one of the input end side resonance element or the output end side resonance element and the one of the input end side resonance element or the output end side resonance element. An input electrode or output provided with a second dielectric layer One and one of the electrodes, it is possible to obtain the first 17 laminated dielectric filter having a.

In the seventeenth laminated dielectric filter, preferably, one end of the input end side resonance element, one end of the output end side resonance element and one end of the internal resonance element are electrically connected to the first ground electrode. The first internal ground electrode is connected to the open end, the other end of the input end side resonance element, the open end side, the other end of the output end side resonance element, and the other end of the internal resonance element. At the open end side, a part of the first main surface of the input end side resonance element, a part of the first main surface of the output end side resonance element, and the first main surface of the internal resonance element. An eighteenth laminated dielectric filter provided to face a part of the surface can be obtained.

In the eighth laminated dielectric filter, it is preferable that the other one of the input-end-side resonance element and the output-end-side resonance element be the second main body on the side opposite to the first main surface. A second surface opposite to the first main surface of the internal resonance element closest to a part of the surface and the other one of the input end side resonance element or the output end side resonance element;
A part of the main surface of the input end side resonance element or the output end side resonance element and the other end of the input end side resonance element or the output end side resonance element. A coupling electrode provided with a second dielectric layer interposed therebetween with the internal resonance element in contact therewith, and a third dielectric layer interposed between the coupling electrode and a part of the coupling electrode opposed to the coupling electrode; With the other of the input electrode or output electrode provided in
Can be obtained.

In the ninth or tenth laminated dielectric filter, preferably, the input terminal side resonance element, the output terminal side resonance element, the internal resonance element, and the second
A part of the other one of the input-end-side resonance element and the output-end-side resonance element and the input-end-side resonance element or the output-end-side resonance A coupling electrode provided so as to face a part of the internal resonance element closest to the other of the elements, the input end side resonance element, the output end side resonance element, the internal resonance element, and the second The second electrode between the ground electrode
A twentieth laminated dielectric filter, further comprising, in the dielectric layer, the other of the input electrode or the output electrode provided to face a part of the coupling electrode.

In the nineteenth laminated dielectric filter, preferably, one end of the input-end-side resonance element, one end of the output-end-side resonance element, and one end of the internal resonance element are electrically connected to the first ground electrode. The first internal ground electrode is connected to the open end, the other end of the input end side resonance element, the open end side, the other end of the output end side resonance element, and the other end of the internal resonance element. At the open end side, a part of the first main surface of the input end side resonance element, a part of the first main surface of the output end side resonance element, and the first main surface of the internal resonance element. A twenty-first laminated dielectric filter provided to face a part of the surface can be obtained.

In the twentieth laminated dielectric filter, preferably, one end of the input end side resonance element, one end of the output end side resonance element and one end of the internal resonance element are electrically connected to the first ground electrode. And the first and second internal ground electrodes are connected to an open end which is the other end of the input end side resonance element, an open end which is the other end of the output end side resonance element, and the internal resonance. On the open end side, which is the other end of the element, preferably, the input end side resonance element, the output end side resonance element, and a part of the first and second main surfaces of the internal resonance element are respectively opposed to each other. A twenty-second laminated dielectric filter provided by the above method can be obtained.

Further, according to the present invention, an input end side resonance element, an output end side resonance element, and at least one internal part arranged in parallel between the input end side resonance element and the output end side resonance element. A resonance element, a first main surface of the input terminal side resonance element, a first main surface of the output terminal side resonance element, and a first main surface of the internal resonance element; A first ground electrode provided with a first dielectric layer interposed between the output-end-side resonance element and the internal resonance element, the input-end-side resonance element, the output-end-side resonance element, In the first dielectric layer between the internal resonance element and the first ground electrode, a part of the first main surface of the input end side resonance element, the first main surface of the output end side resonance element, 1 and a first surface provided opposite to a part of the first main surface of the internal resonance element. A first ground electrode, the input end side resonance element, the output end side resonance element, and the input end side resonance element in the first dielectric layer between the internal resonance element and the first earth electrode. Alternatively, a part of any one of the output-end-side resonance elements and a part of the internal resonance element closest to the input-end-side resonance element or the output-end-side resonance element are provided. The coupling electrode provided in the first dielectric layer between the input terminal side resonance element, the output terminal side resonance element, the internal resonance element, and the first ground electrode. A twenty-third laminated dielectric filter having either the input electrode or the output electrode provided to face the portion can be obtained.

In the twenty-third laminated dielectric filter, preferably, a second main surface of the input end side resonance element opposite to the first main surface, and a second main surface of the output end side resonance element. 1, a second main surface opposite to the first main surface and a second main surface of the internal resonance element opposite to the first main surface, and the input end side resonance element and the output end A twenty-fourth laminated dielectric filter further including a second ground electrode provided with a second dielectric layer interposed between the side resonance element and the internal resonance element can be obtained.

In the twenty-fourth laminated dielectric filter, preferably, the second resonance element between the input terminal side resonance element, the output terminal side resonance element and the internal resonance element and the second ground electrode. In the dielectric layer, a part of the second main surface of the input end side resonance element, a part of the second main surface of the output end side resonance element, and the second main surface of the internal resonance element are provided. A twenty-fifth laminated dielectric filter further including a second internal ground electrode provided to face a part of the surface can be obtained.

In the twenty-third laminated dielectric filter, it is preferable that the other one of the input-end-side resonance element and the output-end-side resonance element be the second main body on the side opposite to the first main surface. A second surface opposite to the first main surface of the internal resonance element closest to a part of the surface and the other one of the input end side resonance element or the output end side resonance element;
Opposing a part of the main surface of the input terminal side resonance element or the output end side resonance element and the other one of the input end side resonance element or the output end side resonance element. A second between the nearest internal resonance element
The other of the input electrode or the output electrode provided with the third dielectric layer interposed between the coupling electrode and the coupling electrode, the coupling electrode being provided with the dielectric layer interposed therebetween. And a twenty-sixth laminated dielectric filter further comprising:

In the twenty-fourth or twenty-fifth laminated dielectric filter, preferably, the input-end resonance element, the output-end resonance element, the internal resonance element, and the second
A part of the other one of the input-end-side resonance element and the output-end-side resonance element and the input-end-side resonance element or the output-end-side resonance A coupling electrode provided to face a part of the internal resonance element closest to the other of the elements, the input-end resonance element, the output-end resonance element, the internal resonance element, and the internal resonance element; A twenty-seventh stacked dielectric further comprising an input electrode or an output electrode provided in the second dielectric layer between the element and the second ground electrode so as to face a part of the coupling electrode; A body filter can be obtained.

In one of the laminated dielectric filters of the twenty-third to the twenty-seventh, preferably, one end of the input end side resonance element, one end of the output end side resonance element, and one end of the internal resonance element are the first end. The first internal ground electrode is the other end of the input end side resonance element, the open end side is the other end of the output end side resonance element, and the first internal ground electrode is the other end of the output end side resonance element. A part of the first main surface of the input end side resonance element, a part of the first main surface of the output end side resonance element, and a part of the internal resonance element on the open end side which is the other end of the resonance element. A twenty-eighth laminated dielectric filter provided to face a part of the first main surface can be obtained.

In one of the twenty-fourth, twenty-fifth, and twenty-seventh laminated dielectric filters, preferably, one end of the input-end-side resonance element, one end of the output-end-side resonance element, and one end of the internal resonance element are connected to each other. Electrically connected to a first ground electrode, wherein the first and second internal ground electrodes are
In the open end side which is the other end of the input end side resonance element, the open end side which is the other end of the output end side resonance element and the open end side which is the other end of the internal resonance element, preferably, the input end It is possible to obtain a twenty-ninth laminated dielectric filter which is provided to face each of the first and second main surfaces of the side resonance element, the output end side resonance element, and the internal resonance element.

Further, according to the present invention, the input end side resonance element, the output end side resonance element, and one or more internal components arranged in parallel between the input end side resonance element and the output end side resonance element. A resonance element, a first main surface of the input terminal side resonance element, a first main surface of the output terminal side resonance element, and a first main surface of the internal resonance element; A first ground electrode provided with a first dielectric layer interposed between the output-end-side resonance element and the internal resonance element, the input-end-side resonance element, the output-end-side resonance element, In the first dielectric layer between the internal resonance element and the first ground electrode, a part of the first main surface of the input end side resonance element, the first main surface of the output end side resonance element, 1 and a first surface provided opposite to a part of the first main surface of the internal resonance element. An internal ground electrode, a part of a second main surface opposite to the first main surface of one of the input end side resonance element and the output end side resonance element, and the input end side resonance element or The input end side resonance element which faces a part of a second main surface of the internal resonance element closest to the one of the output end side resonance elements and which is opposite to the first main surface of the internal resonance element; Alternatively, a second dielectric layer is sandwiched between the one of the output-end-side resonance elements and the internal resonance element that is closest to the one of the input-end-side resonance elements or the one of the output-end-side resonance elements. And an input electrode or an output electrode facing a part of the coupling electrode and having a third dielectric layer interposed between the coupling electrode and the coupling electrode. A thirtieth laminated dielectric filter can be obtained.

[0043] In any one of the first to thirtieth laminated dielectric filters, preferably, the laminated dielectric filter is a thirty-first laminated dielectric filter, which is a comb-line dielectric filter. it can.

[0044]

According to the present invention, an internal ground is provided in a dielectric layer between the resonance element and a ground electrode provided opposite to the resonance element with the dielectric layer interposed therebetween so as to oppose a part of the resonance element. Electrodes are provided. Therefore, the portion of the resonance element facing the internal ground electrode is closer to the ground, and a capacitance is formed between the resonance element and the internal ground electrode. This capacitance also converts the resonance element into an equivalent. Will be added to the capacitance of the parallel resonance circuit when this occurs. Therefore, if the resonance frequency is the same, the inductance of the parallel resonance circuit can be reduced, the length of the resonance element becomes shorter, and the length of the entire laminated dielectric filter becomes shorter.

Further, the portion of the resonance element facing the internal ground electrode is closer to the ground, and the coupling with the ground is strengthened. Therefore, the coupling between the resonance elements in the portion facing the internal ground electrode is weak. Become. Therefore, the coupling between the resonance elements mainly occurs at a portion that does not overlap with the internal ground electrode. This means that the electrical length of the resonance element has been substantially shortened. When the electrical length is shortened in this way, the reactance of the distributed constant element that couples the resonance elements is also reduced, and the resonance elements are strongly coupled to each other, thereby broadening the filter characteristics.

Further, one of an input electrode and an output electrode is provided so as to oppose a part of the input end side resonance element and a part of the output end side resonance element with the dielectric layer interposed therebetween, or A part of one of the input-end resonance element or the output-end resonance element and a part of the internal resonance element closest to one of the input-end resonance element or the output-end resonance element with the body layer interposed therebetween; By providing one of the input electrode and the output electrode in opposition to the above, an inductance is connected in series to one of the input-end resonance element and the output-end resonance element, and the band-pass filter An attenuation peak is generated on the higher side of the pass band.

Further, a dielectric layer is sandwiched between one of the input-end resonance element and the output-end resonance element and the internal resonance element closest to one of the input-end resonance element and the output-end resonance element. By providing one of the input electrode and the output electrode on one side of the input electrode and the output terminal by providing one of the input electrode and the output electrode with a dielectric layer interposed therebetween in a part of the coupling electrode. The capacitance is connected in series to the resonance element, and an attenuation peak is generated on the lower side of the pass band of the band-pass filter.

[0048]

Embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a schematic development view of the first embodiment of the present invention, and FIG. 2 is a perspective view of the first embodiment.

A part of the open ends of the resonance elements 21, 22, and 23 described later overlaps with the dielectric layers 11 and 15 therebetween.
An internal earth electrode 81 whose end is electrically connected to a later-described earth electrode 70 is formed on the surface of the dielectric layer 14.
The ground electrode 70 is also formed later on the back surface of the dielectric layer 14.

A part of the resonance element 23 on the output end side described later overlaps with a part of the resonance element 22 adjacent to the resonance element 23 with the dielectric layer 11 interposed therebetween, and is substantially orthogonal to the resonance element 23 and the resonance element 22. The output electrode 42 to be formed is
Formed on the surface of Note that the output electrode 42 is formed to have a narrow width at a predetermined length including a portion facing the resonance element 22.

One end is electrically connected to a ground electrode 70, which will be described later, to form a quarter wavelength strip line resonator. Further, one end is electrically connected to a ground electrode 70 described later, and the other end is separated from the open ends of the resonance elements 21 to 23 by a predetermined distance, and respectively connected to the resonance elements 21 to 23. Opposing electrode 31
To 33 are formed on the surface of the dielectric layer 11 so that the resonance element 2
A comb-line type filter is configured by utilizing the fact that each of the components 1 to 23 is distributed-coupled. The resonance element 21 is a resonance element on the input end side, and the resonance element 23 is a resonance element on the output end side.

Dielectric layer 16 laminated on dielectric layer 11
Of the resonance element 21 on the input end side and the resonance element 2
An input electrode 41 that overlaps with a part of the resonance element 22 adjacent to 1 through the dielectric layer 16 is formed and that is substantially orthogonal to the resonance element 23 and the resonance element 22. The input electrode 41 is formed to have a narrow width at a predetermined length including a portion facing the resonance element 22.

The dielectric layers 16 and 17 overlap with part of the open ends of the resonance elements 21, 22 and 23 with the dielectric layers 16 and 17 interposed therebetween. It is formed on the surface of the body layer 17.

On the dielectric layer 17, a ground electrode 70 is formed on the surface.
Are laminated, and a dielectric layer 14,
15, 11, 16, 17, and 13 are integrally formed.

The integrally formed dielectric layers 14, 15, 1
1, 16, 17, 13 upper and lower surfaces and an input terminal portion 61,
As shown in FIG. 2, a ground electrode 70 is formed on the side surface excluding the output terminal portion 62. Further, in the input terminal portion 61 on one side surface of the integrally formed dielectric layers 14, 15, 11, 16, 17, and 13, it is electrically insulated from the ground electrode 70 and electrically connected to the input electrode 41. Is formed in the output terminal portion 62 on the other side of the integrally formed dielectric layers 14, 15, 11, 16, 17, and 13. An output terminal 52 electrically insulated and electrically connected to the output electrode 42 is formed.

In this embodiment configured as described above,
First, only the spatial configuration of the resonance elements 21 to 23, the electrodes 31 to 33, the input electrode 41, and the output electrode 42 is shown in a plan view and a sectional view taken along line XX of FIG. 3 and FIG. It is. Resonant elements 21 and 22 and input electrode 41
There is an overlapping portion with the dielectric layer 16 interposed therebetween, and the overlapping portion including the dielectric layer 16 is in a state of being electrostatically coupled. This capacitance is referred to as capacitance 4
01 and 403. There is also an overlapping portion between the resonance elements 23 and 22 and the output electrode 42 with the dielectric layer 11 interposed therebetween, and the overlapping portion including the dielectric layer 11 is in a state of being electrostatically coupled. These capacitances are referred to as capacitances 402 and 404, respectively.

Further, capacitances 121, 122, and 123 are formed between the open ends of the resonance elements 21, 22, and 23 and the electrodes 31, 32, and 33, respectively. The presence of these capacitances 121 to 123 causes the resonance elements 21, 22, and 23 to have an inductance 41.
1 and 412, respectively.

As described above, the electrical equivalent circuit of the filter composed of the resonance elements 21 to 23, the electrodes 31 to 33, the input electrode 41 and the output electrode 42 is as shown in FIG. If the inductance 411, the capacitance 401, and the capacitance 403 in FIG. 5 are subjected to Δ-Y conversion, the input-side capacitance 111 and the coupling capacitance 113 in FIG.
And an inductance 1 connected in series with the resonance element 21
31, the inductance 412 and the capacitance 4
02, when the capacitance 404 is Δ-Y converted, the inductance 132 is connected in series with the output-side capacitance 112, the coupling capacitance 114, and the resonance element 23 in FIG. Therefore, the equivalent circuit of FIG. 5 becomes the equivalent circuit of FIG.
It exhibits bandpass characteristics.

As described above, the filter having the above configuration equivalently has a state in which the inductance 131 is connected in series with the resonance element 21 and a state in which the inductance 132 is connected in series with the resonance element 23, and the bandpass An attenuation peak is generated on the high band side of the pass band of the filter.

The frequency at which the peak of the attenuation occurs varies depending on the capacitance 403 and the capacitance 404.

However, when the thickness of the dielectric layer 16 is constant, the capacitance 403 is set by the facing area of the resonance element 32 and the input electrode 41 with the dielectric layer 16 interposed therebetween. 404 is set by the facing area between the resonance element 22 and the output electrode 42 with the dielectric layer 11 interposed therebetween, while the width of the resonance element 22 and the width of the input electrode 41 and the output electrode 42 are relatively set. Because it is easy, the opposing area of the resonance element 22 and the input electrode 41 and the resonance element 2
It is also easy to set the facing area between the second electrode 2 and the output electrode 42 without variation. Therefore, by setting these opposing areas without variation, it is possible to suppress variations in the frequency at which the peak of attenuation occurs.

Further, in this embodiment, FIG.
As shown in FIG. 3, the width of the input electrode 41 is set to be narrow over a predetermined length including a portion facing the resonance element 22. There is almost no variation in the area facing the electrode 41, and as a result, a change in the capacitance 403 can be small.
In addition, since the width of the output electrode 42 is set to be narrow over a predetermined length including a portion facing the resonance element 22, even if the position of the resonance element 22 is shifted, the distance between the resonance element 22 and the output electrode 42 is reduced. There is almost no variation in area, and as a result, a change in the capacitance 404 is small. For this reason, the width of the input electrode 41 is not set to be narrow over a predetermined length including the portion opposing the resonance element 22, and the capacitance of the same capacitance value is formed (see FIG. 7A). An attenuation peak occurs more than when the capacitance of the same capacitance value is formed without setting the width of the output electrode 42 narrow over a predetermined length including the portion facing the resonance element 22 (see FIG. 7B). Frequency fluctuations can be further reduced.

Further, the inductances 411 and 412
Are obtained by inductive coupling between the resonance elements 21, 22 and 23, and the capacitances 401 and 403 are obtained by the dielectric layer 16 and the resonance elements 21 and 22.
22 and the input electrode 41, the capacitance 40
Since the components 2 and 404 are obtained by the dielectric layer 11, the resonance elements 22 and 23, and the output electrode 42, no separate components are required, and the size can be reduced.

Next, the resonance elements 21 to 23 and the electrodes 31 to 3
FIG. 8 is a plan view and a sectional view taken along line YY of a spatial configuration in the case where internal earth electrodes 81 and 82 are added to the configuration of FIG. 3 including the input electrode 41 and the output electrode 42 in FIG.
And as shown in FIG. Capacitors 141 and 142 are formed between the resonance element 21 and the internal ground electrodes 81 and 82, respectively.
Capacitances 143 and 144 are formed between the resonant element 23 and the internal ground electrodes 81 and 82, respectively.

FIG. 10 shows an equivalent circuit of the laminated dielectric filter configured as described above. The capacitances 141, 142, 143, 144, and
145 and 146 are added.

Next, the operation and effect of the internal earth electrode used in the present invention will be described.

First, consider the case where there are two comb-line type resonance elements 321 and 322 as shown in FIG. The electrical lengths of the resonance elements 321 and 322 are both θ. FIG. 12 is an equivalent circuit diagram of the comb line type wiring of FIG. Here, assuming that the even mode impedance of the resonance elements 321 and 322 is Z _e and the odd mode impedance is Z ₀ , the characteristic impedance Z _C of the distributed constant element 323 that couples the resonance elements 321 and 322 in a distributed manner.
Is

[0069]

(Equation 1)

Is obtained. Furthermore, this characteristic impedance Z
_The impedance Z viewed from the open side of the line _C is Z =
jZ _C tan θ.

FIG. 13 shows the relationship between the reactance Z _C tan θ of the impedance Z and the electrical length θ. When θ = 90 ° (ie, １ ／ wavelength), the reactance Z _C tan θ of the distributed constant element 323 becomes ∞, and it can be seen that there is no coupling between the resonance elements 321 and 322. Next, if the electrical length θ is shorter than １ ／ wavelength, that is, if 0 <θ <90 °, tan
θ becomes a finite value, the reactance Z _C tan θ of the distributed constant element 323 also becomes a finite value, and the resonance elements 321 and 32
2 are coupled, and the smaller the value of θ, the smaller the reactance Z _C tan θ, and the stronger the coupling. In this case, that is, when 0 <θ <90 °, the value of Z _C tan θ is positive, so that the distributed constant element 323 is represented as an inductance.

Here, referring again to FIGS. 8, 9 and 10, the internal ground electrodes 81 and 82 are partially
1 to 23, the resonance element 2
On the open end sides of the internal ground electrodes 81, 8
2 is closer to the ground, and the coupling with the ground becomes stronger, so that the coupling between the resonance elements 21 to 23 in the part overlapping with the internal ground electrodes 81 and 82 is weakened.
Therefore, the coupling between the resonance elements 21 to 23 is mainly performed at a portion that does not overlap with the internal earth electrodes 81 and 82. This means that the coupling electrical length θ of the resonance elements 21 to 23 is substantially equal to the length of the portion that does not overlap with the internal ground electrodes 81 and 82. When the coupling electrical length θ of the resonance elements 21 to 23 is reduced in this manner, the reactance Z _C tan θ of the distributed constant element 323 that couples the resonance elements 21 to 23 is also reduced.
To 23 are more strongly coupled to each other, so that the filter characteristics can be broadened.

Further, since the electrodes 31 to 33 are provided, the capacitances 121 to 33 are provided between the resonance elements 21 to 23 and the ground.
123 are added, but by further providing the internal ground electrodes 81 and 82, the resonance elements 21 to 2
Between the internal ground electrodes 81 and 82 and the capacitance 14
1 and 142, 143 and 144, 145 and 1
46 are formed, and these capacitances are also added between the resonance elements 21 to 23 and the ground. Therefore, the capacitance of the parallel resonance circuit shown in FIG.
1, 231 and the sum of these added capacitances, and if the resonance frequencies are the same, the inductance of the parallel resonance circuit can be smaller. Therefore, the lengths of the resonance elements 21 to 23 are further reduced, and the overall length of the multilayer dielectric filter is also reduced.

Further, the input electrode 41 and the output electrode 42 are located with the dielectric layers interposed therebetween with respect to the surface on which the resonance elements 21 to 23 are formed.
The input electrode 41 and the output electrode 42 are connected to the resonance elements 21 to 2.
3 is electrostatically shielded. Therefore, there is almost no floating capacitance between the input electrode 41 and the output electrode 42. As a result, the attenuation characteristics of the band-pass filter are improved.

Next, a method for manufacturing the multilayer dielectric filter of the first embodiment will be described.

The present laminated dielectric filter has the resonance elements 21 to
23, electrodes 31 to 33, input electrode 41, output electrode 4
2 and the internal earth electrodes 81 and 82 are completely incorporated in the dielectric, so that the resonance elements 21 to 23 and the electrodes 31 to 3
3. It is desirable to use a low-resistance, low-resistance specific electrode as the input electrode 41 and the output electrode 42, and it is preferable to use a low-resistance Ag-based or Cu-based conductor.

As the dielectric to be used, a ceramic dielectric which is highly reliable and has a large dielectric constant εγ and can be miniaturized is preferable.

As a manufacturing method, after a conductor paste is applied to a molded body of ceramic powder to form an electrode pattern, each molded body is laminated and further baked to be densified, and the conductor is laminated therein. It is desirable to integrate it with the ceramic dielectric in a state where the ceramic dielectric is in a closed state.

When using Ag-based or Cu-based conductors, their melting points (1100 ° C. or lower) are low because they have low melting points and are difficult to co-fire with ordinary dielectric materials. It is necessary to use a dielectric material that can be fired at a lower temperature. Further, due to the nature of the device as a microwave filter, the temperature characteristic (temperature coefficient) of the resonance frequency of the formed parallel resonance circuit is ± 50 ppm / ° C.
The following dielectric materials are preferred. Examples of such a dielectric material, for example, those of glass-based mixtures of cordierite glass powder and TiO ₂ powder and Nd ₂ Ti ₂ O ₇ powder and, BaO-TiO ₂ -Re ₂ O
₃ -Bi ₂ O ₃ based compositions (Re: rare earth component) to that added some glass forming component or glass powder, barium oxide - titanium oxide - adding some glass powder neodymium oxide based dielectric magnetic composition powder There is something.

As an example, MgO: 18 wt% -Al ₂
O ₃ : 37 wt% -SiO ₂ : 37 wt% -B ₂ O ₃ :
73 wt% of glass powder having a composition of 5 wt% -TiO ₂ : 3 wt%, 17 wt% of commercially available TiO ₂ powder, and N
10 wt% of the d ₂ Ti ₂ O ₇ powder was sufficiently mixed to obtain a mixed powder. Note that Nd ₂ Ti ₂ O ₇ powder is Nd ₂ O
After calcining the ₃ powder and the TiO ₂ powder at 1200 ° C., those obtained by pulverization were used. Next, an acrylic organic binder, a plasticizer, toluene and an alcohol-based solvent were added to the mixed powder, and the mixture was sufficiently mixed with alumina cobblestone to form a slurry. Then, using this slurry, a green sheet having a thickness of 0.2 mm to 0.5 mm was produced by a doctor blade method.

Next, in the case of the first embodiment, the conductor patterns shown in FIG. 1 are printed using silver paste as the conductor paste, and then the thickness of the green sheet on which these conductor patterns are printed is adjusted. For this reason, necessary green sheets were stacked to form the structure shown in FIG. 1, stacked, and then fired at 900 ° C.

The two main surfaces of the laminated dielectric filter body configured as described above, that is, the entire back surface of the dielectric layer 14 and the front surface of the dielectric layer 13, the input terminal portion 61, and the output terminal portion 62 are formed. As shown in FIG. 2, an earth electrode 70 made of a silver electrode is printed on the other side, and is electrically insulated from the earth electrode 70, and the input electrode 41 and the output electrode 4
2, silver terminals electrically connected to the input terminal 61,
The input terminal 51 and the output terminal 52 were printed in the output terminal section 62, and the printed electrodes were baked at 850 ° C.

In the above-described laminated dielectric filter, the width w ₁ of each of the resonance elements 21 to 23 is 0.8 mm,
The distance s1 between ₁ and 23 is 1.2 mm, and the resonance elements 21 and 2
3, the length l ₁ is 4 mm, and the width w _{2 of the} electrodes 31 to 33 is 0.
8 mm, the length l ₂ of the electrodes 31 to 33 is 0.5 mm, the interval s ₂ between the electrodes 31 to 33 is 1.2 mm, and the resonance elements 21 to 2
3 and the distance s ₃ between the electrodes 31 to 33 respectively facing them and 0.3 mm, and the input electrode 41 resonant element 21
0.96 mm ² , the input electrode 41 and the resonance element 22 have an opposing area of 0.08 mm ² , and the output electrode 4
2 and the resonance element 23 are 0.96 mm ² , and the opposing area between the output electrode 42 and the resonance element 22 is 0.08 mm.
^2. The thickness of the dielectric layers 14, 15, 11, 16, 17, 13 is 1.5 mm, 0.2 mm, 0.2 mm,
0.2 mm, 0.2 mm, and 1.5 mm, the width w ₃ of the internal ground electrodes 81 and 82 is 5.4 mm, the length l ₃ of the internal ground electrodes 81 and 82 is 1.8 mm, and the internal ground electrode 8 is used.
1 and each of the opposing areas of the resonance elements 21 to 23 are set to 0.
8 mm ² , internal ground electrode 82 and each of resonance elements 21 to 23
Are 0.8 mm ² , and each resonance element 21
23 are exposed from the internal earth electrodes 81 and 82.
_{When 4} is 3 mm, the outer shape is 6.0 mm × 4.8.
mm × 3.8mm, center frequency 1100MH
z, the bandwidth was 75 MHz, and the insertion loss was 2.5 dB or less. Further, the frequency of the attenuation peak was 1280 MHz, and the amount of attenuation at that time was 50 dB. When 30 filters were made, the variation of the frequency of the attenuation peak had a standard deviation of 3 MHz.

As for the input electrode 41, FIG.
As shown in (a), the portion facing the resonance element 22 is not thinned, and the area facing the input electrode 41 and the resonance element 22 is the same as when the facing portion is narrowed. Also, as shown in FIG.
2, the center frequency is 1100 MHz, and the bandwidth is 72 MHz.
z, the insertion loss was 2.5 or less. The frequency of the attenuation peak was 1250 MHz, and the amount of attenuation at that time was 35 dB. When I made 30 filters,
The standard deviation is 8MHz for the variation of the frequency of the attenuation peak.
The variation in the frequency of the attenuation peak was larger than when the facing portion was made thinner.

For comparison, using the green sheet used in the first embodiment, the internal ground electrode 81 was not provided on the surface of the dielectric layer 14 and the internal ground electrode 81 was also provided on the surface of the dielectric layer 17. Without the ground electrode 82, the resonance elements 21 to
23 of the length l ₁ and the multilayer dielectric filter itself a length l ₅ lengthened, the other when configured as in the first embodiment (Comparative Example 1), the center frequency of the first embodiment Same 110
To obtain 0 MHz, the length l ₁ of the resonance elements 21 to 23 should be 7
There needs to be mm, the first embodiment also the length l ₅ of the laminated dielectric filter itself is prolonged and 7.8mm compared to was 4.8 mm. And the bandwidth is also 15MHz
Which is smaller than that of the first embodiment. As described above, it can be seen that the bandwidth is greatly improved and the dimensions of the multilayer dielectric filter itself are reduced by the first embodiment.

For comparison, the input electrode 41 provided on the dielectric layer 16 was opposed to the resonance element 22 using the green sheet used in the first embodiment, as shown in FIG. The output electrode 42 provided on the dielectric layer 15 does not face the resonance element 22, and is opposed to the resonance element 21 only (the facing area is 0.78 mm ² ).
Only (opposed area 0.78 mm ² )
(Comparative Example 2), the center frequency was 1100 MHz, the bandwidth was 80 MHz, and the insertion loss was 2.4 dB or less. In this case, there was no attenuation peak, and the attenuation at a frequency point 150 MHz higher than the center frequency was 25 dB. Thus, it can be seen that the attenuation characteristics on the high frequency side are also improved by the first embodiment.

Next, as a second embodiment of the present invention, the first embodiment
As shown in FIG. 15, the output electrode 42 provided on the dielectric layer 15 is not opposed to the resonance element 22 but is opposed to only the resonance element 23 by using the green sheet used in the embodiment of FIG. The structure was the same as that of the first example except for 0.78 mm ² ). As a result, the center frequency 1100M
Hz, the bandwidth was 78 MHz, and the insertion loss was 2.5 dB or less. Further, the frequency of the attenuation peak was 1310 MHz, and the amount of attenuation at that time was 60 dB or less.

Next, as a third embodiment of the present invention, the first embodiment
As shown in FIG. 16, the input electrode 41 provided on the dielectric layer 16 is not opposed to the resonance element 22 but is opposed to only the resonance element 21 by using the green sheet used in the embodiment of FIG. The structure was the same as that of the first example except for 0.78 mm ² ). As a result, the center frequency 1100M
Hz, the bandwidth was 78 MHz, and the insertion loss was 25 dB or less. Further, the frequency of the attenuation peak was 1310 MHz, and the amount of attenuation at that time was 60 dB or less.

The second and third embodiments are different from the first embodiment in that
1. Compared with Comparative Example 2 in which neither the output electrode 42 nor the center resonance element 22 is opposed, by setting one of the input electrode 41 and the output electrode 42 to face the resonance element 22, It can be seen that the side attenuation characteristics are improved.

Next, comparing the second and third embodiments with the first embodiment in which both the input electrode 41 and the output electrode 42 face the resonance element 22, respectively, the input electrode 4
In the first embodiment in which both the first electrode 1 and the output electrode 42 face the resonance element 22, the second and third embodiments in which one of the input electrode 41 and the output electrode 42 faces the resonance element 22. It can be seen that the attenuation characteristics on the high frequency side are more improved than in the example of FIG.

Next, a fourth embodiment of the present invention will be described.
FIG. 17 is a schematic development view of the present embodiment, FIG. 18 is a plan view showing a configuration of a main part of the present embodiment, and FIGS. 19 and 20 are sectional views taken along line XX and YY of FIG. 18, respectively. .

Although the first to third embodiments have exemplified the case where the number of the resonance elements is three, in the present embodiment, the number of the resonance elements is two, and in this case, FIG. 17 to FIG. As shown, in the first embodiment, the resonance element 22 and the electrode 32 are removed, the resonance element 21 and the resonance element 23 are distributed-coupled, and one of the resonance elements 21 is sandwiched between the dielectric layers 16.
An input electrode 41 is provided to face the portion of the resonant element 23 and an output electrode 42 is provided to face the portion of the resonant element 23 and the portion of the resonant element 21 with the dielectric layer 11 interposed therebetween. I just need.

The electrical equivalent circuit in this case is as shown in FIG. 21. In this case, the same operation as in the first embodiment is performed. Here, the capacitance 40
5, the capacitance 407 indicates the capacitance between the resonance element 21 and the resonance element 23 and the input electrode 41, and the capacitance 406 and the capacitance 408 indicate the capacitance between the resonance element 23 and the resonance element 21 and the output. The inductance between the resonance element 21 and the resonance element 2.
3 is the inductance of the inductive coupling between them.

Next, a method of manufacturing the laminated dielectric filter of this embodiment will be described. Also in this embodiment, the first
Using the green sheets used in the above Examples, the conductor patterns shown in FIG. 17 were printed using silver paste as the conductor paste, and then the green sheets necessary for adjusting the thickness of the green sheets on which these conductor patterns were printed were used. Are stacked so as to have the structure of FIG.
After lamination, it was fired at 900 ° C.

Both main surfaces of the laminated dielectric filter body configured as described above, that is, surfaces corresponding to the entire back surface of the dielectric layer 14,
As shown in FIG. 2, a ground electrode 70 made of a silver electrode is printed on the front surface corresponding surface of the dielectric layer 13, except for the input terminal portion 61 and the output terminal portion 62, and further electrically insulated from the ground electrode 70. In addition, silver electrodes electrically connected to the input electrode 41 and the output electrode 42 are printed as the input terminal 51 and the output terminal 52 in the input terminal 61 and the output terminal 62, respectively. I baked it.

In the above-mentioned laminated dielectric filter,
The width w of the resonance elements 21 and 23₁0.8 mm and the resonance element
The distance s between the element 21 and the resonance element 23₁1.2mm, resonance
Length l of elements 21 and 23₁Of 4 mm, the electrodes 31 and 33
Width w_Two0.8 mm, the length l of the electrodes 31 and 33_TwoTo 0.
5 mm, interval s between electrode 31 and electrode 33_Two1.2m
m, the resonance elements 21 and 23 and the
Spacing s between poles 31 and 33 _ThreeTo 0.3 mm
The facing area between the pole 41 and the resonance element 21 is 1.2 mm ^Two, Enter
The facing area between the force electrode 41 and the resonance element 23 is 0.1 mm
^Two, The opposing area between the output electrode 42 and the resonance element 23 is set to 1.
2mm^TwoArea between the output electrode 42 and the resonance element 21
0.1 mm^Two, Dielectric layers 14, 15, 11, 16, 1
The thicknesses of 7, 13 are 1.5 mm, 0.2 mm, respectively.
0.2mm, 0.2mm, 0.2mm, 1.5mm
And the width w of the internal earth electrodes 81 and 82_ThreeIs 3.4 mm,
Length l of internal earth electrodes 81 and 82_Three1.8mm inside
Area between the ground electrode 81 and each of the resonance elements 21 and 23
0.8 mm each^Two, Internal ground electrode 82 and each resonance
The area facing each of the elements 21 and 23 is 0.8 mm^Two,
Each of the resonance elements 21 and 23 is
Exposed length l_FourIs 3 mm, the outer shape is 3.
8 mm x 4.0 mm x 4.8 mm, and the center frequency is
1100 MHz, bandwidth 65 MHz, insertion loss 1.
It was 8 dB or less. Furthermore, the frequency of the attenuation peak is 13
00 MHz, and the attenuation at that time was 40 dB.
Was.

For comparison, using the green sheet used in the fourth embodiment, the internal ground electrode 81 was not provided on the surface of the dielectric layer 14 and the internal ground electrode 81 was also provided on the surface of the dielectric layer 17. Without the ground electrode 82, the resonance element 21,
23 of the length l ₁ and the multilayer dielectric filter itself a length l ₅ lengthened, the other when configured similarly to the fourth embodiment (Comparative Example 3), the center frequency and the fourth embodiment Same 110
To obtain 0 MHz, the length l ₁ of the resonance elements 21 and 23 should be 7
mm, and the length l _{5 of the} laminated dielectric filter itself was 7.8 mm longer than that of the fourth embodiment, which was 4.8 mm. And the bandwidth is also 12MHz
Which is smaller than that of the fourth embodiment. As described above, it can be seen that the bandwidth is significantly improved and the dimensions of the multilayer dielectric filter itself are also reduced according to the fourth embodiment. Further, for comparison, using the green sheet used in the fourth embodiment, as shown in FIG. 22, the input electrode 41 provided on the dielectric layer 16 was not opposed to the resonance element 23, and element 21 only to face (facing area 0.9 mm ^2), the output electrode 42 provided on the dielectric layer 15 is also not facing the resonance element 21, is opposed only resonant element 23 (facing area 0.9 mm ² ), The other configuration is the same as that of the first embodiment (Comparative Example 4).
00MHz, bandwidth 70MHz, insertion loss 1.7d
B or less. In this case, there was no attenuation peak, and the attenuation at a frequency point 200 MHz higher than the center frequency was 25 dB. Thus, it can be seen that the attenuation characteristics on the high frequency side are also improved by the fourth embodiment.

Next, as a fifth embodiment of the present invention, the fourth embodiment
23, the output electrode 42 provided on the dielectric layer 15 does not face the resonance element 21 but faces only the resonance element 23 as shown in FIG. 0.9 mm ² ), and the other configuration was the same as that of the first embodiment. As a result, the center frequency 1100 MH
z, the bandwidth was 68 MHz, and the insertion loss was 1.7 dB or less. Further, the frequency of the attenuation peak was 1370 MHz, and the amount of attenuation at that time was 50 dB or less.

Next, as a sixth embodiment of the present invention, the first
As shown in FIG. 24, the input electrode 41 provided on the dielectric layer 16 is not opposed to the resonance element 23, but is opposed to only the resonance element 21 by using the green sheet used in the example (the facing area). 0.9 mm ² ), and the other configuration was the same as that of the first embodiment. As a result, the center frequency 1100 MH
z, the bandwidth was 68 MHz, and the insertion loss was 1.7 dB or less. Further, the frequency of the attenuation peak was 1370 MHz, and the amount of attenuation at that time was 50 dB or less.

The fifth and sixth embodiments are replaced with the input electrode 4
1. Compared with Comparative Example 4 in which neither the output electrode 42 faces the center resonance element 22, either the input electrode 41 or the output electrode 42 faces the resonance elements 21 and 23. As a result, it is understood that the attenuation characteristic on the high frequency side is improved.

Next, comparing the fifth and sixth embodiments with the fourth embodiment in which both the input electrode 41 and the output electrode 42 face the resonance elements 21 and 23, Both the electrode 41 and the output electrode 42 are connected to the resonance elements 21 and 2.
The fourth embodiment, which faces the input electrode 4, faces the input electrode 4.
1. It can be seen that the attenuation characteristics on the high frequency side are more improved than in the fifth and sixth embodiments in which one of the output electrodes 42 is opposed to the resonance elements 21 and 23.

The number of resonance elements may exceed three,
For example, when the resonance element 24 is provided between the resonance elements 22 and 23, and the coupling between the resonance element 22 and the resonance element 24 is inductive coupling, the electrical equivalent circuit becomes as shown in FIG. The element 22 and the resonance element 24 form a circuit connected by the inductance 414. In this case, the same operation as in the above embodiment is performed.

In the case where the coupling between the resonance element 22 and the resonance element 24 is capacitive coupling, as shown in FIG. 26, the electrical equivalent circuit has a capacitance 415 instead of the inductance 414 in FIG. Resonant element 22 and resonant element 24
Are connected, but also in this case, the same operation as in the above-described embodiment is performed.

As described above, when the number of the resonance elements is four or more,
The coupling between the resonance elements 21 and 22 and the coupling between the resonance elements 24 and 23 need to be inductive coupling.
The coupling between 2 and the resonance element 24 may be inductive coupling or capacitive coupling.

Next, a seventh embodiment of the present invention will be described.

FIG. 27 is a schematic development view of the present embodiment, and FIG. 2 is a perspective view of the present embodiment.

An internal ground which overlaps a part of the open ends of the resonance elements 21, 22, and 23 described later with the dielectric layers 11, 18 and 15 interposed therebetween and whose end is electrically connected to a ground electrode 70 described later. An electrode 81 is formed on the surface of the dielectric layer. The ground electrode 70 is also formed later on the back surface of the dielectric layer 14.

The dielectric layer 1 is formed on a part of the coupling electrode 91 described later.
An output electrode 42 that overlaps with the electrode 8 and that is substantially perpendicular to the resonance element 23 is formed on the surface of the dielectric layer 15.
On the surface of the dielectric layer 18 laminated on the dielectric layer 15, a part of the resonance element 23 on the output end side and a part of the resonance element 22 adjacent to the resonance element 23 are overlapped with the dielectric layer 11 interposed therebetween. The coupling electrode 91 is formed so as to be substantially orthogonal to the resonance elements 23 and 22.

One end is electrically connected to a ground electrode 70 to be described later, and the resonance elements 21 to 23 constituting the quarter wavelength strip line resonator are stacked on the dielectric layer 15. Further, one end is electrically connected to a ground electrode 70 described later, and the other end is separated from the open ends of the resonance elements 21 to 23 by a predetermined distance, and respectively connected to the resonance elements 21 to 23. Opposing electrode 31
To 33 are formed on the surface of the dielectric layer 11 so that the resonance element 2
A comb-line type filter is configured by utilizing the fact that each of the components 1 to 23 is distributed-coupled. The resonance element 21 is a resonance element on the input end side, and the resonance element 23 is a resonance element on the output end side.

Dielectric layer 16 laminated on dielectric layer 11
Of the resonance element 21 on the input end side and the resonance element 2
An input electrode 41 that overlaps with a part of the resonance element 22 adjacent to 1 through the dielectric layer 16 is formed and that is substantially orthogonal to the resonance element 23 and the resonance element 22. The input electrode 41 is formed to have a narrow width at a predetermined length including a portion facing the resonance element 22.

A part of the open ends of the resonance elements 21, 22, and 23 overlaps with the dielectric layers 16 and 17 interposed therebetween, and an inner ground electrode 82 whose end is electrically connected to a later-described ground electrode 70 is insulated. It is formed on the surface of the body layer 17.

On the dielectric layer 17, a ground electrode 70 is formed on the surface.
Are laminated, and a dielectric layer 14,
15, 18, 11, 16, 17, and 13 are integrally formed.

The integrated dielectric layers 14, 15, 1
As shown in FIG. 2, a ground electrode 70 is formed on the upper and lower surfaces of 8, 11, 16, 17, and 13 and on the side surfaces excluding the input terminal portion 61 and the output terminal portion 62. Further, the integrally formed dielectric layers 14, 15, 18, 11, 16, 17, 13
An input terminal 51 which is electrically insulated from the ground electrode 70 and is electrically connected to the input electrode 41 is formed in the input terminal portion 61 on one side surface. Body layers 14, 15, 18, 11, 16, 17,
13, the ground electrode 7 is provided in the output terminal 62 on the other side.
An output terminal 52 that is electrically insulated from 0 and electrically connected to the output electrode 42 is formed.

In this embodiment configured as described above,
Resonant elements 21 to 23, electrodes 31 to 33, input electrode 4
1, the spatial configuration of the output electrode 42, the coupling electrode 91, and the internal earth electrodes 81 and 82 is a plan view,
28, 29, and 30, respectively, as shown in the line sectional view and the line YY thereof. Resonant element 2
There is an overlapping portion between the first and second electrodes 22 and the input electrode 41 with the dielectric layer 16 interposed therebetween, and the overlapping portion including the dielectric layer 16 is in a state of being electrostatically coupled. These capacitances are referred to as capacitances 401 and 403, respectively. Also,
There is also an overlapping portion between the resonance elements 23 and 22 and the coupling electrode 91 with the dielectric layer 11 interposed therebetween, and the overlapping portion including the dielectric layer 11 is in a state of being electrostatically coupled.
These capacitances are referred to as capacitances 116 and 117, respectively. Furthermore, there is an overlapping portion between the coupling electrode 91 and the output electrode 42 with the dielectric layer 18 interposed therebetween.
1 are electrostatically coupled in the overlapping portion. This capacitance is referred to as capacitance 115.

Further, between the open ends of the resonance elements 21, 22 and 23 and the electrodes 31, 32 and 33, the capacitance 1
21, 122, and 123 are formed. Further, capacitances 141 and 142 are respectively formed between the resonance element 21 and the internal earth electrodes 81 and 82, and capacitances 143 and 142 are formed between the resonance element 22 and the internal earth electrodes 81 and 82, respectively.
144 are formed, and capacitances 145 and 146 are formed between the resonance element 23 and the internal earth electrodes 81 and 82, respectively. And these capacitances 12
1 to 123 and 141 to 146,
The resonance elements 21, 22, and 23 have inductances 411 and 4,
12, respectively.

As described above, the electric equivalent circuit of the filter composed of the resonance elements 21 to 23, the electrodes 31 to 33, the input electrode 41 and the output electrode 42, the coupling electrode 91 and the internal earth electrodes 81 and 82. Is as shown in FIG. If Δ-Y conversion is performed on the inductance 411, the capacitance 401, and the capacitance 403 in FIG.
2, the input-side capacitance 111 and the coupling capacitance 113
And an inductance 1 connected in series with the resonance element 21
It becomes 31. Further, in a configuration like the present embodiment,
The inductances 412 can be absorbed by the capacitances 116, 117, and 115, and the resonance elements 22 and 2 can be absorbed.
The coupling of 3 is capacitive. The capacitance is indicated by capacitance 118 in FIG.

As described above, in the filter having the above configuration, the inductance 1 is equivalently connected in series with the resonance element 21.
31 is connected, and an attenuation peak is generated on the high band side of the pass band of the band-pass filter. In addition, the capacitance 116 is equivalently connected in series to the resonance element 23, and an attenuation peak is generated on the lower side of the pass band of the band-pass filter.

As described above, on the input side, the resonance element 2
While the attenuation peak is provided on the high frequency side using the inductance 411 between the resonance elements 1 and 22, the capacitance 1 between the resonance elements 22 and 23 and the coupling electrode 91 is provided on the output side.
17 and 116, the resonance element 2
The inductance 412 between 3 and 22 is the capacitance 11
7, it is necessary to keep it small.
Therefore, in the present embodiment, the interval between the resonance elements 23 and 22 is set to be larger than the interval between the resonance elements 21 and 22.
The inductance 412 is reduced.

The frequency at which the high-frequency attenuation peak occurs varies depending on the capacitance 403. However, when the thickness of the dielectric layer 16 is constant, the capacitance 403 is
Since the width of the resonance element 32 and the width of the input electrode 41 are relatively easy to set while being set by the facing area between the resonance element 32 and the input electrode 41 with the dielectric layer 16 interposed therebetween, It is also easy to set the facing area between the electrode and the input electrode 41 without variation. Therefore, also in the present embodiment, by setting the facing area without variation, it is possible to suppress variation in frequency at which an attenuation peak on the high frequency side occurs.

Further, also in this embodiment, FIG.
Since the width of the input electrode 41 is set to be narrow over a predetermined length including a portion opposed to the resonance element 22 as shown in FIG. There is almost no variation in the area of the opposing surface 41, and as a result, the change in the capacitance 403 is small. For this reason, also in the present embodiment, when the capacitance of the same capacitance value is formed without setting the width of the input electrode 41 narrow over a predetermined length including the portion facing the resonance element 22 (FIG. 7).
As compared with (a)), the fluctuation of the frequency at which the attenuation peak occurs can be further reduced.

The frequency at which the low-frequency side attenuation peak occurs varies due to the capacitance 116 connected in series to the resonance element 23. However, assuming that the thickness of the dielectric layer 11 is constant, the area of the coupling electrode 91 opposed to the resonance element 23 with the dielectric layer 11 interposed therebetween allows the capacitance connected in series to the resonance element 23 to be increased. 116 can be set arbitrarily. Further, as shown in FIGS. 33A and 33B, the width of the coupling electrode 91 is set to be constant over the range where the resonance element 21 is picked up, so that the relative position between the resonance element 21 and the coupling electrode 91 can be changed. Even if the displacement occurs, there is no change in the capacitance 116, and the setting of the relative position between the resonance element 21 and the coupling electrode 91 during the production is further facilitated. Therefore, there is no variation in the low-frequency cutoff characteristics of the multilayer dielectric filter of this embodiment.

The inductance 411 corresponds to the resonance element 2
1 and 22 are obtained by inductive coupling, and the capacitances 401 and 40 are obtained.
3 is a dielectric layer 16, resonance elements 21 and 22, and an input electrode 4
1, the capacitances 117 and 116 are obtained by the dielectric layer 11, the resonance elements 22 and 23, and the coupling electrode 91, and the capacitance 115 is obtained by the dielectric layer 18 and the coupling electrode 91.
And the output electrode 42, no additional components are required, and miniaturization is possible.

The functions and effects of the internal earth electrodes 81 and 82 used in this embodiment are the same as those in the first to sixth embodiments. That is, the internal ground electrodes 81 and 82
As a result, the resonance elements 21 to 23 are more strongly coupled to each other, and the filter characteristics can be broadened. If the resonance frequency is the same, the resonance element 21
23 are also shorter, and the overall length of the laminated dielectric filter is also shorter.

Also in this embodiment, the input electrode 4
1 and the output electrode 42 are electrostatically shielded by the resonance elements 21 to 23. Therefore, the input electrode 41
The stray capacitance between the output electrode 42 and the output electrode 42 is almost eliminated. As a result, the steepness of the frequency characteristic of the bandpass filter is also improved.

Next, a method of manufacturing the multilayer dielectric filter of this embodiment will be described. Also in this embodiment, the first
Using the green sheets used in the above Examples, the conductor patterns shown in FIG. 27 were printed using silver paste as the conductor paste, and then the green sheets necessary for adjusting the thickness of the green sheets on which these conductor patterns were printed were used. Are stacked so that the structure of FIG. 27 is obtained.
After lamination, it was fired at 900 ° C.

The two main surfaces of the laminated dielectric filter body configured as described above, that is, the entire back surface of the dielectric layer 14 and the front surface of the dielectric layer 13, the input terminal portion 61, and the output terminal portion 62 are formed. As shown in FIG. 2, an earth electrode 70 made of a silver electrode is printed on the other side, and is electrically insulated from the earth electrode 70, and the input electrode 41 and the output electrode 4
2, silver terminals electrically connected to the input terminal 61,
The input terminal 51 and the output terminal 52 were printed in the output terminal section 62, and the printed electrodes were baked at 850 ° C.

In the above-described laminated dielectric filter, the width w ₁ of each of the resonance elements 21 to 23 is 0.8 mm,
The distance s ₁ between the _first and second elements 22 is 1.2 mm,
2.0mm spacing s ₄ between 3, 4 mm length l ₁ of the resonance element 21 to 23, the width w ₂ of the electrode 31 to 33 0.8 m
m, the length l ₂ of the electrodes 31 to 33 is 0.7 mm, and the electrode 3
1,32 1.2 mm spacing s ₂ of, 2.0 mm spacing s ₅ of the electrodes 32, 33, 0.3 m spacing s ₃ between the electrodes 31 to 33 respectively facing them and the resonance element 21 to 23
and m, input 0.64 mm ² facing area between the electrode 41 and the resonance element 21, coupling electrode 91 and the resonance element respectively 1.12 mm ² the opposing area between 23, 22, 0.4 mm ^2,
The facing area between the output electrode 42 and the coupling electrode 91 is 0.9 m.
m ² , dielectric layers 14, 15, 18, 11, 16, 17,
13 are 1.3 mm, 0.2 mm, 0.2 mm respectively.
mm, 0.2mm, 0.2mm, 0.2mm, 1.5m
m and the width w ₃ of the internal ground electrodes 81 and 82 is 1.4 m.
m, the length l ₃ of the internal ground electrodes 81 and 82 is 6.2 m
m, the opposing area between the internal ground electrode 81 and each of the resonance elements 21 to 23 is 0.32 mm ² , and the internal ground electrode 82
And the opposing area of each of the resonance elements 21 to 23 is 0.3
2 mm ² , each of the resonance elements 21 to 23 is
Assuming that the length l ₄ exposed from 1, 82 is 3.6 mm, the outer shape is 3.8 mm × 5.0 mm × 7.2 mm, the center frequency is 1480 MHz, and the bandwidth is 80 MHz.
z, the insertion loss was 2.4 dB or less. Further, the frequency of the attenuation peak on the high frequency side was 1720 MHz, and the amount of attenuation at that time was 60 dB. The frequency of the attenuation peak on the low frequency side was 1290 MHz, and the attenuation at that time was 65 dB. When 30 filters were manufactured, the standard deviation of the frequency of the attenuation peak on the high frequency side was 5 MHz, and the standard deviation of the frequency of the attenuation peak on the low frequency side was 4 MHz.

For comparison, using the green sheet used in the seventh embodiment, the output electrode 42 provided on the dielectric layer 15 was directly provided without the coupling electrode 91 provided on the dielectric layer 18. In the case where only the resonance element 23 is opposed (the opposed area is 0.5 mm ² ) and the other configuration is the same as that of the seventh embodiment (Comparative Example 5), the center frequency is 1480 MHz, the bandwidth is 83 MHz, and the insertion loss is 2.4 dB. It was below. The frequency of the attenuation peak on the high frequency side was 1710 MHz, and the amount of attenuation at that time was 55 dB. However, in this case, there was no attenuation peak on the low frequency side, and the attenuation at a frequency point 250 MHz lower than the center frequency was 35 dB. Thus, it can be seen that the seventh embodiment also improves the attenuation characteristic on the low frequency side.

Further, even when the input electrode 41 of this embodiment is connected to the output terminal 52 and the output electrode 42 is connected to the input terminal 51, the same characteristics as those of this embodiment were obtained.

Also in this embodiment, the number of resonance elements may exceed three. For example, a resonance element 24 is provided between the resonance elements 22 and 23, and the coupling between the resonance element 22 and the resonance element 24 is performed. In the case of inductive coupling, the electrical equivalent circuit is as shown in FIG.
Is a circuit connected by the inductance 414. In this case, the same operation as in the above-described embodiment is performed.

In the case where the coupling between the resonance element 22 and the resonance element 24 is capacitive coupling, as shown in FIG. 35, the electrical equivalent circuit has a capacitance 415 instead of the inductance 414 shown in FIG. Resonant element 22 and resonant element 2
4 is connected, but in this case, the same operation as in the above-described embodiment is performed.

When the number of resonance elements is four or more, the coupling between the resonance elements 21 and 22 is inductive coupling, and the coupling between the resonance elements 24 and 23 needs to be capacitive coupling.
The coupling between the resonance element 22 and the resonance element 24 may be inductive coupling or capacitive coupling.

In each of the above embodiments, the case where the internal ground electrodes 81 and 82 do not face the input electrode 41, the output electrode 42 and the coupling electrode 91 has been described. Electrode 41, output electrode 4
The present invention can be applied to a case where any one or all of the electrodes 2 and the coupling electrode 91 face each other and overlap with each other.

[0134]

According to the present invention, a part of a resonance element is provided in a dielectric layer between a ground electrode provided opposite to the resonance element with the dielectric layer interposed therebetween and the resonance element. Since the internal ground electrode is provided, the laminated dielectric filter can have a wide band and can be downsized.

Further, one of an input electrode and an output electrode is provided so as to face a part of the input end side resonance element and a part of the output end side resonance element with the dielectric layer interposed therebetween, or
Part of one of the input-end resonance element and the output-end resonance element and part of the internal resonance element closest to one of the input-end resonance element and the output-end resonance element with the dielectric layer interposed therebetween In this case, one of the input electrode and the output electrode is provided in opposition to the above, so that an attenuation peak is generated on the high band side of the pass band of the band-pass filter, and the attenuation characteristic on the high band side is improved.

Further, a dielectric layer is sandwiched between one of the input-end resonance element and the output-end resonance element and the internal resonance element closest to one of the input-end resonance element and the output-end resonance element. Since a coupling electrode is provided to face each other, and one of the input electrode and the output electrode is provided on a part of the coupling electrode with a dielectric layer interposed therebetween, an attenuation peak occurs on the lower side of the pass band of the band-pass filter. Thus, the attenuation characteristic on the low frequency side is improved.

[Brief description of the drawings]

FIG. 1 is a schematic development view of a laminated dielectric filter according to a first embodiment of the present invention.

FIG. 2 is a perspective view of the multilayer dielectric filter according to the first embodiment of the present invention.

FIG. 3 is a plan view showing a configuration of a main part of the multilayer dielectric filter according to the first embodiment of the present invention.

FIG. 4 is a sectional view taken along line XX of FIG. 3;

FIG. 5 is an equivalent circuit diagram of the filter shown in FIG.

FIG. 6 is an equivalent circuit diagram of the circuit of FIG. 5;

FIG. 7 is a plan view for explaining a positional relationship between a resonance element, an input electrode, and an output electrode.

FIG. 8 is a plan view showing a configuration of a main part of the multilayer dielectric filter according to the first embodiment of the present invention.

FIG. 9 is a sectional view taken along line YY of FIG. 8;

FIG. 10 is an equivalent circuit diagram of the filter shown in FIG.

FIG. 11 is a diagram for explaining a comb-line type resonance element.

FIG. 12 is an equivalent circuit diagram of the wiring of FIG. 11;

13 is a distributed constant element 3 in the equivalent circuit diagram of FIG.
It is a figure which shows the relationship between the reactance of 23 impedance, and an electrical length.

FIG. 14 is a plan view showing a configuration of a main part of a multilayer dielectric filter of Comparative Example 2.

FIG. 15 is a plan view showing a configuration of a main part of a multilayer dielectric filter according to a second embodiment of the present invention.

FIG. 16 is a plan view showing a configuration of a main part of a multilayer dielectric filter according to a third embodiment of the present invention.

FIG. 17 is a schematic developed view of a multilayer dielectric filter according to a fourth embodiment of the present invention.

FIG. 18 is a plan view showing a configuration of a main part of a multilayer dielectric filter according to a fourth embodiment of the present invention.

FIG. 19 is a sectional view taken along line XX of FIG. 18;

FIG. 20 is a sectional view taken along line YY of FIG. 18;

21 is an equivalent circuit diagram of the filter shown in FIG.

FIG. 22 is a plan view showing a configuration of a main part of a multilayer dielectric filter of Comparative Example 4.

FIG. 23 is a plan view showing a configuration of a main part of a multilayer dielectric filter according to a fifth embodiment of the present invention.

FIG. 24 is a plan view showing a configuration of a main part of a multilayer dielectric filter according to a sixth embodiment of the present invention.

FIG. 25 is an equivalent circuit diagram when the number of resonance elements is increased in the first embodiment of the present invention.

FIG. 26 is an equivalent circuit diagram when the number of resonance elements is increased in the first embodiment of the present invention.

FIG. 27 is a schematic developed view of a multilayer dielectric filter according to a seventh embodiment of the present invention.

FIG. 28 is a plan view showing a configuration of a main part of a multilayer dielectric filter according to a seventh embodiment of the present invention.

29 is a sectional view taken along line XX of FIG. 28.

30 is a sectional view taken along line YY of FIG. 28.

FIG. 31 is an equivalent circuit diagram of the filter shown in FIG. 28.

FIG. 32 is an equivalent circuit diagram of the circuit in FIG. 28;

FIG. 33 is a plan view for explaining a positional relationship between a coupling electrode and a resonance element in a seventh embodiment of the present invention.

FIG. 34 is an equivalent circuit diagram when the number of resonance elements is increased in the seventh embodiment of the present invention.

FIG. 35 is an equivalent circuit diagram when the number of resonance elements is increased in the seventh embodiment of the present invention.

FIG. 36 is a schematic development view of a conventional laminated dielectric filter devised by the present inventors.

FIG. 37 is a perspective view of a conventional laminated dielectric filter devised by the present inventors.

FIG. 38 is an equivalent circuit diagram of a conventional laminated dielectric filter devised by the present inventors.

[Explanation of symbols]

 11, 13 to 17 dielectric layers 21 to 23 resonant elements 31 to 33 electrodes 41 input electrodes 42 output electrodes 81 and 82 internal ground electrodes

 ──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-5-243810 (JP, A) JP-A-4-284003 (JP, A) JP-A-5-95202 (JP, A) JP-A-5-95202 275903 (JP, A) JP-A-5-191105 (JP, A) JP-A-61-258503 (JP, A) US Patent 4,418,324 (US, A)

Claims (6)

(57) [Claims] An input end side resonance element, an output end side resonance element, and a first main surface of the input end side resonance element and a first main surface of the output end side resonance element. A first ground electrode provided between the end-side resonance element and the output-end-side resonance element with a first dielectric layer interposed therebetween; the input-end-side resonance element and the output-end-side resonance element; In the first dielectric layer between the first dielectric layer and the ground electrode;
A first internal ground electrode provided to face a part of the first main surface of the input end side resonance element and a part of the first main surface of the output end side resonance element; In the first dielectric layer between the end-side resonance element and the output-end-side resonance element and the first ground electrode,
A multilayer dielectric filter comprising: an input electrode or an output electrode provided to face a part of the input end side resonance element and a part of the output end side resonance element. . 2. An input end side resonance element, an output end side resonance element, one or more internal resonance elements arranged in parallel between the input end side resonance element and the output end side resonance element, A first main surface of an end-side resonance element, a first main surface of the output-end-side resonance element, and a first main surface of the internal resonance element; A first ground electrode provided between the element and the internal resonance element with a first dielectric layer interposed therebetween; and the input-end resonance element, the output-end resonance element, the internal resonance element, and the first ground electrode. A part of the first main surface of the input-end-side resonance element and a part of the first main surface of the output-end-side resonance element in the first dielectric layer between the first and second ground electrodes; A first internal ground electrode provided to face the portion and a part of the first main surface of the internal resonance element; The input end side resonance element or the output end side is provided in the first dielectric layer between the input end side resonance element, the output end side resonance element, the internal resonance element and the first ground electrode. An input electrode provided to face a part of any one of the resonance elements and a part of the internal resonance element closest to the input terminal side resonance element or the one of the output end side resonance elements; A laminated dielectric filter, comprising: any one of output electrodes. 3. An input end side resonance element, an output end side resonance element, and a first main surface of the input end side resonance element and a first main surface of the output end side resonance element, A first ground electrode provided between the end-side resonance element and the output-end-side resonance element with a first dielectric layer interposed therebetween; the input-end-side resonance element and the output-end-side resonance element; In the first dielectric layer between the first dielectric layer and the ground electrode;
A first internal ground electrode provided to face a part of the first main surface of the input end side resonance element and a part of the first main surface of the output end side resonance element; A part of a second main surface of the end-side resonance element opposite to the first main surface and a second main surface of the output-end resonance element opposite to the first main surface; One of an input electrode and an output electrode provided so as to face a part thereof and provided with a second dielectric layer interposed between the input-end-side resonance element and the output-end-side resonance element. A laminated dielectric filter characterized by the following. 4. An input-end resonance element, an output-end resonance element, one or more internal resonance elements arranged in parallel between the input-end resonance element and the output-end resonance element, A first main surface of an end-side resonance element, a first main surface of the output-end-side resonance element, and a first main surface of the internal resonance element; A first ground electrode provided between the element and the internal resonance element with a first dielectric layer interposed therebetween; and the input-end resonance element, the output-end resonance element, the internal resonance element, and the first ground electrode. A part of the first main surface of the input-end-side resonance element and a part of the first main surface of the output-end-side resonance element in the first dielectric layer between the first and second ground electrodes; A first internal ground electrode provided to face the portion and a part of the first main surface of the internal resonance element; A part of a second principal surface of the input terminal side resonance element or the output terminal side resonance element opposite to the first principal surface and the input terminal side resonance element or the output terminal side resonance element; The input end side resonance element or the output end side facing a part of a second main surface opposite to the first main surface of the internal resonance element closest to the one of the elements; An input provided with a second dielectric layer interposed between the one of the resonance elements and the internal resonance element closest to the one of the input-end resonance element or the output-end resonance element; A laminated dielectric filter comprising: an electrode and an output electrode. 5. An input-end resonance element, an output-end resonance element, one or more internal resonance elements arranged in parallel between the input-end resonance element and the output-end resonance element, A first main surface of an end-side resonance element, a first main surface of the output-end-side resonance element, and a first main surface of the internal resonance element; A first ground electrode provided between the element and the internal resonance element with a first dielectric layer interposed therebetween; and the input-end resonance element, the output-end resonance element, the internal resonance element, and the first ground electrode. A part of the first main surface of the input-end-side resonance element and a part of the first main surface of the output-end-side resonance element in the first dielectric layer between the first and second ground electrodes; A first internal ground electrode provided to face the portion and a part of the first main surface of the internal resonance element; The input end side resonance element or the output end side is provided in the first dielectric layer between the input end side resonance element, the output end side resonance element, the internal resonance element and the first ground electrode. A coupling electrode provided so as to face a part of any one of the resonance elements and a part of the internal resonance element that is closest to the one of the input-end resonance element or the output-end resonance element; The input end side resonance element, the output end side resonance element, the internal resonance element, in the first dielectric layer between the first ground electrode, and facing a part of the coupling electrode. A laminated dielectric filter, comprising: either an input electrode or an output electrode provided. 6. An input-end resonance element, an output-end resonance element, one or more internal resonance elements arranged in parallel between the input-end resonance element and the output-end resonance element, A first main surface of an end-side resonance element, a first main surface of the output-end-side resonance element, and a first main surface of the internal resonance element; A first ground electrode provided between the element and the internal resonance element with a first dielectric layer interposed therebetween; and the input-end resonance element, the output-end resonance element, the internal resonance element, and the first ground electrode. A part of the first main surface of the input-end-side resonance element and a part of the first main surface of the output-end-side resonance element in the first dielectric layer between the first and second ground electrodes; A first internal ground electrode provided to face the portion and a part of the first main surface of the internal resonance element; A part of a second principal surface of the input terminal side resonance element or the output terminal side resonance element opposite to the first principal surface and the input terminal side resonance element or the output terminal side resonance element; The input end side resonance element or the output end side facing a part of a second main surface opposite to the first main surface of the internal resonance element closest to the one of the elements; A coupling provided with a second dielectric layer between the one of the resonance elements and the internal resonance element closest to the one of the input-end resonance element or the output-end resonance element. An electrode, and one of an input electrode and an output electrode provided so as to face a part of the coupling electrode and sandwich a third dielectric layer between the coupling electrode and the coupling electrode. Stacked dielectric filter.