JP3193101B2 - 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 filter used for high-frequency devices such as portable telephones and a laminated dielectric filter used for an antenna duplexer, and more particularly to a laminated dielectric filter whose frequency characteristics can be adjusted. Related to body filters.

[0002]

2. Description of the Related Art As shown in FIGS. 10 (a), 10 (b) and 10 (c), for example, a conventional laminated dielectric filter has a resonance element 2 composed of a strip line on the surface of a dielectric layer 20. FIG.
1 to 23 are printed on the resonance element 21 so that the input electrode 25 is electrically connected thereto, and the resonance element 23 is printed and formed on the resonance element 21 so that the output electrode 27 is electrically connected thereto. The dielectric layer 28 is laminated on the surface of the dielectric layer 20 and then fired to be integrated. The peripheral surface of the integrated dielectric layer filter is electrically connected to one end of the resonance elements 21 to 23, and The ground electrode 29 is printed except for the terminal portion 31 and the output terminal portion 32, and is electrically insulated from the ground electrode 29 and electrically connected to the input electrode 25 in the input terminal portion 31 and the output terminal portion 32, respectively. Input terminal 24
The electrode as an output terminal 26 electrically connected to the output electrode 27 while being electrically insulated from the electrode and the ground electrode 29 is printed and fired.

[0003] After firing, it is checked whether or not the frequency characteristic of the laminated dielectric filter is a predetermined frequency characteristic. However, due to variations in the printing accuracy of the resonance element, variations in the dielectric constant of the dielectric layer, shrinkage during firing, variations in the firing temperature, and the like, the frequency characteristics may not be the predetermined characteristics. In this case, Japanese Patent Publication No. 61-19122
As disclosed in Japanese Patent Application Laid-Open Publication No. H11-163, the center frequency and the like of the frequency characteristics of the multilayer dielectric filter are adjusted by removing a portion 291 facing the vicinity of the open end of the resonance element of the ground electrode 29.

[0004]

The frequency characteristic is determined by the resonance frequency of the resonance element forming the filter.
However, the center frequency adjustment range of the frequency characteristic by partially removing the ground electrode in the conventional laminated dielectric filter as described above is about several MHz to 10 MHz,
There is only a narrow adjustment range. On the other hand, the variation of the center frequency usually reaches 30 MHz due to the above-described variation and the like, and there is a problem that it is difficult to sufficiently adjust the frequency characteristics with the conventional laminated dielectric filter. Further, there is another problem that the removal of the ground electrode portion near the open end of the resonance element affects the coupling between the resonance elements.

SUMMARY OF THE INVENTION An object of the present invention is to provide a laminated dielectric filter which can adjust the center frequency in a wide range and can easily perform minute adjustment.

[0006]

According to the present invention, there is provided a laminated dielectric filter according to the present invention, wherein one end of a strip line is electrically connected to a ground electrode to constitute a laminated dielectric filter, and one or more resonant elements constituting the laminated dielectric filter; A plurality of electrodes respectively formed on a plurality of dielectric layers stacked on one main surface of the element are provided in the dielectric, and the plurality of electrodes are opposed to the open ends of the corresponding resonance elements, and With the dielectric layer interposed,
The resonator is formed so as to overlap with the vibration element in a plane, and in order to adjust the resonance frequency of the opposing resonance element, the electrical connection with the ground electrode is cut off according to the adjustment amount of the resonance frequency. .

[0007]

According to the laminated dielectric filter of the present invention, since the dielectric layer is interposed between the resonance element and the electrode facing the resonance element, a capacitance exists between the resonance element and the electrode. The capacitance is connected in parallel to the parallel resonance circuit composed of resonance elements, and by adjusting the number of electrodes that are electrically disconnected from the ground electrode, the capacitance connected in parallel to the parallel resonance circuit decreases. The number of electrodes that are adjusted in the direction and the resonance frequency of the resonance element is adjusted in the higher direction, and are electrically cut off from the ground electrode corresponding to the deviation of the center frequency of the frequency characteristic of the multilayer dielectric filter from the target value. The required frequency can be adjusted by increasing / decreasing the frequency.

[0008] This adjustment can be performed by scraping a part of the ground electrode including one end portion of the electrode, so that the adjustment can be easily performed. Further, by setting the size and the number of electrodes facing the resonance element, fine adjustment and coarse adjustment can be performed, and fine adjustment can be performed.

Further, when the electrode facing the resonance element overlaps the resonance element via the dielectric layer, a large capacitance value is easily obtained as compared with the case where the electrode does not overlap. It becomes easy to control to a suitable value.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to embodiments.

FIG. 1 is a schematic development view of the first embodiment of the present invention, FIG. 2 is a perspective view of the first embodiment of the present invention, and FIG.
FIG. 2 is a plan view and a cross-sectional view showing a configuration of a main part of the first embodiment of the present invention.

[0012] extends into one end of the dielectric layer 1 _1,
A plurality of constituting the dielectric layer 1 ₁ of the strip line resonator having one end portion described later to the ground electrode 2 formed on the entire back surface is formed with a slightly shorter strip line than 1/4 wavelength that is electrically connected the resonant element 3 ₁ to 3 ₃ are formed parallel to the surface of the dielectric layer 1 _1. Further, the dielectric layer 1
One end portion extending to the other end of _one is electrically connected to the ground electrode 2, and the other end resonator 3 ₁ to 3 ₃ and the other end from the (open end) apart predetermined intervals resonant element 3 _The electrodes 4 ₁ , 4 ₂ , 4 ₃ facing each of _{1 to} 3 ₃ are connected to the dielectric layer 1.
Formed on _one of the surfaces, constituting a combline filter by utilizing the fact that the resonant element 3 ₁ to 3 ₃ inductances due to resonance element 3 ₁ to 3 ₃ each distribution coupling is inductive coupling.

[0013] The dielectric layer 1 ₂ laminated on the dielectric layer 1 ₁
On the surface of the resonant element 3 of the _input side across the dielectric layer 1 ₂
Some overlap, one end dielectric layer 1 extends to one end of the ₂ to the input terminal 9 ₁ is electrically connected, resonant element 3 input electrode 5 ₁ so as to be substantially perpendicular to _one forming a similarly across the dielectric layer 1 ₂ on the surface of the dielectric layer 1 ₂ overlaps a portion of the resonant element 3 _{and second} output side, one end extends to the other end portion of the dielectric layer 1 ₂ It is electrically connected to the output terminal 9 ₂ Te, to form an output electrode 5 ₂ so as to be substantially perpendicular to the resonant element 3 _2.

Further, the dielectric layer 1_TwoThe surface of the dielectric layer
1_TwoElectrode 4 sandwiching₁, 4_Two, 4_ThreeTo each separately
Opposite, one end is dielectric layer 1_TwoExtending to the other end of the
It is electrically connected to the ground electrode 2 and the other end is a resonance element.
Child 3₁~ 3_ThreeDielectric layer 1_TwoElectrodes that overlap each other across
6₁, 6_Two, 6_ThreeTo form Furthermore, the dielectric layer 1
_TwoDielectric layer 1 laminated thereon_ThreeDielectric layer 1 on the surface of_Three
Electrode 6₁, 6 _Two, 6_ThreeEach facing each other
And one end is a dielectric layer 1_ThreeExtend to the other end of the
The electrode 6 is electrically connected to the₁, 6_Two, 6_Threeof
Longer than the length and the other end is the resonance element 3₁~ 3_ThreeTo dielectric
Body layer 1_TwoAnd 1_ThreeElectrodes 7 overlapping each other across₁, 7
_Two, 7_ThreeTo form

Further, the dielectric layer 1_ThreeDielectric laminated on top
Body layer 1_FourDielectric layer 1 on the surface of_FourElectrode 7₁, 7
_Two, 7_Three, And one end faces the dielectric layer 1
_FourExtending to the other end of the
Electrode 7₁, 7_Two, 7 _ThreeLonger than the length of
The end is the resonance element 3₁~ 3_ThreeDielectric layer 1_Two~ 1_FourAcross
The electrodes 8 overlapping each other₁, 8_Two, 8_ThreeForming a dielectric
Layer 1_FourA dielectric layer on which a ground electrode 2 is formed
1_FiveTo form a dielectric layer 1₁~ 1_FiveIs composed integrally,
Front and back surfaces and input terminal section 10₁And output terminal 1
0_TwoThe ground electrode 2 is formed by applying the ground electrode 2 to the side surfaces excluding the above.

On the other hand, the integrally formed dielectric layers ₁₁ to ₁₅
On one side of the grounding electrode 2 and the electrically insulating, the input electrode 5 ₁ and the input terminal 9 ₁ electrically connected to form the input terminal unit 10 _1, further similarly constructed integrally to the other side surface of the dielectric layer 1 ₁ to 1 _5, ground electrode 2 and the electrically insulating, the output electrodes 5 ₂ and electrically connected to the output terminal 9 ₂ an output terminal portion 10 in ₂ Form.

In the first embodiment configured as described above,
And the resonance element 3₁, Electrode 4₁, Input electrode 5₁, Electrode 6
₁, Electrode 7₁And electrode 8₁The spatial configuration of the top view
FIG. 3 (a) is a schematic view, and FIG.
3 (b), as shown by the solid line, where
And the dielectric layer 1_Two, 1_Three, 1_FourFacing each other
Electrode 4₁, Input electrode 5₁, Electrode 6₁,
7₁, 8₁And the resonance element 3₁Between the other end of
Capacitance 4C₁, 5C₁, 6C₁, 7C₁, 8C₁Exists
Exist. Here, the resonance element 3₁And input electrode 5₁Between
Of capacitance 5C ₁Is the input coupling capacitance. further,
Electrode 4₁, 6₁, 7₁, 8₁Is connected to the ground electrode 2
The book constructed as above because it is connected pneumatically
The electrical equivalent circuit of the first embodiment is the resonance element 3₁Compatible with
If only the part to be changed is shown, as shown in FIG.
Child 3₁Capacitance 4C₁, 6C₁, 7C₁, 8C₁Average
The circuits are connected in columns.

[0018] The above relationship is resonant element 3 ₂ and the electrode 4 _2, 6
_2, 7 _2, 8 ₂ for a same as the capacitance 4C ₂ between each the resonant element 3 ₂ of the other end, 6
C _2, 7C _2, 8C ₂ is present, the capacitance 4C _2, 6C _2, 7C _2, 8C ₂ are connected in parallel to the resonant element 3 _2. Similarly, the resonant element 3 ₃ and the electrode 4 _3, output electrode 5 _2, the electrodes 6 _3, 7 _3, 8 ₃ and the same applies to the electrostatic capacitance 4C ₃ between the other end of the resonant element 3 ₃ , 5C ₂ , 6
C _3, 7C _3, 8C ₃ is present, the capacitance 4C _3, 6C _3, 7C _3, 8C ₃ are connected in parallel to the resonant element 3 _3. Here, the input electrode 5 ₁ is the resonance element 3 _2,
The coupling capacitance formed between the output electrode 5 ₂ is absent is a matter of course.

After the firing, the laminated dielectric filter of the first embodiment constructed as described above is checked whether or not the frequency characteristic is a predetermined frequency characteristic. In this check, not the frequency characteristic to a predetermined characteristic, when adjusting the center frequency by adjusting the resonant frequency of the resonant element 3 _1, 3 _2, 3 _3, be described the case of the resonant elements 3 ₁ Examples if, electrodes 4 _1, 6 _1, 7 ₁ or 8 ₁ of peeling the portion of the earth electrode 2 including an end portion electrically connected to and is part, or more end electrically connected to the electrodes, The adjustment is performed by peeling off the portion of the ground electrode 2 including the portion which is provided. FIG. 5 shows an example of this adjustment.
A is as shown in (a), showing an example in which the removal of the portion 2 ₁ of the ground electrode 2 including an end portion electrically connected to it are part of FIGS. 5 (a) in the electrode 8 _1.

Therefore, in this case, FIG.
As shown in FIG.₁Has been removed
The state becomes electrically equivalent to₁Resonance of
The frequency is changed. The electrode 4₁, 6₁, 7₁One
Ground electrode 2 including a portion electrically connected to the end
The resonance element 3 can be₁Resonance frequency
The number can be adjusted. Therefore, as shown in FIG.
Vibrating element 3₁Variable capacitance V in parallel with the parallel resonance circuit
c₁(= 4C₁+ 6C₁+ 7C₁+ 8C₁) Is connected
Electrode 4₁, 6₁, 7₁, 8₁One
Ground electrode 2 including a portion electrically connected to the end
Is peeled off, the ground electrode 2 is peeled off.
Variable capacitance by the capacitance of the electrode facing the
Capacity Vc ₁Decrease, and the resonance element 3₁
Can be adjusted. Also, the resonance element
Child 3_TwoAnd 3_ThreeThe same applies to the adjustment of the resonance frequency of
is there.

Here, the capacitance connected in parallel to the resonance element is different from that of the electrode 6 of the present embodiment because the electrodes are provided in the same layer.
_{1-6 3,} 7 _{1-7 3,} 8 _1-8 it is large when the overlap sandwiching the dielectric layer as _3, together with the can be increased adjusting the amount of change in the resonant frequency, the resonant element 3 _1, 3 _2, 3 ₃ of the resonance frequency can be adjusted independently. Further, capacitance is added to the resonant element 3 ₁ to 3 ₃ as great as electrode located in a position close to the resonant element 3 ₁ to 3 _3, moves away, the resonant element 3 ₁
To 3 the thickness of the dielectric layer of between ₃ and thickens, and by the action of the electrostatic shield electrode present therebetween, the capacitance added to the resonant element 3 ₁ to 3 ₃ are resonant element 3 _{1 to} 3 ₃
It gets smaller as it gets farther away from. However, this book
In the embodiment, the lengths of the electrodes are set to electrodes 6 _{1 to} 6 ₃ <electrodes 7 ₁ to
7 ₃ <electrode 8 ₁ to 8 ₃ , the electrode 6 ₁
6 ₃ , the electrodes 7 _{1 to} 7 ₃ , and the electrodes 8 ₁ to 8 ₃ , when the respective electrodes are cut off from the ground electrode 2, the changes in capacitance can be made substantially equal, and the resonance frequency can be easily adjusted. is there.

[0022] Here, the resonant element 3 ₁ Vc ₁ parallel connected variable capacitance, the characteristic impedance of the resonant element 3 ₁ Z, each frequency omega, the electrical length of the resonant element 3 ₁ at that frequency omega θ, the resonance condition is Ztan θ = 1
/ A ωVc _1. Therefore, the larger the variable capacitance Vc _1, the electrical length θ is reduced, the length of the resonant element 3 ₁ is shortened and miniaturized. The same applies to the resonant element 3 ₂ and 3 _3.

Next, a second embodiment of the present invention will be described. The laminated dielectric filter of the second embodiment is shown in FIG.
As shown by the broken line in the electrodes ₆₁ through ₃ of the first embodiment described above, 7 _{1-7 3,} 8 _{1-8 3} further correspondingly, the resonant element 3 _1, 3 _2, 3 ₃ of the back Electrode 6 on the side
_{1-6 3,} 7 _{1-7 3,} 8 _{1-8 3} symmetrically electrodes 61 ₁ to 61 _3, respectively, 71 _{1-71 3} 81 _{1-81 3}
Is provided. The resonant frequency of the resonant element 3 ₁ to 3 ₃ According to this structure, the can be further significantly adjusted than in the first embodiment.

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

In a first modification of the second embodiment of the present invention, as shown in FIG. 6, electrodes 6 _{1 to} 6 ₃ , 7 _{1 to} 7 ₃ , 8 ₁ to 8 ₃ ,
61 _{1 to} 61 ₃ , 71 _{1 to} 71 ₃ and 81 _{1 to} 81 ₃
Are set to the same length. In this case, the electrode ₆₁ through
_3, 7 _{1-7 3,} 8 _{1-8 3,} 61 _{1-61 3} 71 ₁
-71 ₃ and 81 ₁ to 81 for the substantially equal _third electrode length, variable capacitance Vc as when electrically cut off the electrode located at a position away from the resonant element 3 ₁ to 3 ₃ to the earth electrode 2 _1, the amount of change in Vc _2, Vc ₃ is low, it is possible to finely adjust the resonant frequency of the resonant element 3 ₁ to 3 _3.

FIG. 7 shows a second modification of the second embodiment of the present invention.
As shown, the electrode length was changed to electrode 6₁~ 6_Three, 61₁~ 61_Three,
> 7₁~ 7_Three, 71₁~ 71_Three> 8₁~ 8_Three, 81₁~
81 _ThreeIs set to. In the second modification, the electrode length
Is configured in this manner, the resonance element 3₁~ 3_ThreeAway from
The electrode located at the position is electrically disconnected from the ground electrode 2.
Variable capacitance Vc₁, Vc_Two, Vc_ThreeStrange
The amount of conversion is reduced, and the resonance element 3₁~ 3_ThreeResonance frequency
Can be finely adjusted.

Here, the constituent materials of the laminated dielectric filter of each embodiment described above will be described.

It is preferable to use a conductor having a small loss and a low specific resistance for the resonance elements 3 _{1 to} 3 _3.
It is preferable to use a copper-based or Cu-based conductor. As the dielectric material, it is preferable to use ceramics because it has high reliability, a large dielectric constant, and is suitable for miniaturization. As a method of forming the ceramic dielectric layer,
After laminating a dielectric powder compact and a conductor forming the resonance element and the electrode applied on the compact, it is desirable that the conductor be densified by firing and the conductor be integrated in a laminated structure.

In the multilayer dielectric filter of the second embodiment constructed in the above-described manner, each of the resonance elements 3 _{1 to} 3 _{3 is provided.}
Is 0.8 mm, the distance between the resonance elements 3 ₁ and 3 ₂ and the distance between the resonance elements 3 ₁ and 3 ₃ are 1.2 mm,
_{1-3 3} The length and 4 mm, the resonant element 3 ₁ to 3 ₃ 0.2mm per the electrode ₆₁ through ₃ in the vertical, the electrodes 61 ₁ to 61
_3, the electrode 7 _{1-7 3,} electrodes 71 ₁ to 71 _3, electrodes 8 ₁
8 _3, the provided electrodes 81 ₁ to 81 _3, the resonant element 3 ₁ to 3 ₃
The electrode ₆₁ through _3, the electrode 61 ₁ to 61 ₃ and 0.9mm length overlap of the resonant elements 3 ₁ to 3 ₃ and the electrode 7 _{1-7 3,}
Electrodes 71 ₁ to 71 ₃ and 0.8mm length overlap of the resonant elements 3 ₁ to 3 ₃ and the electrode 8 _{1-8 3,} electrodes 81 ₁ to 81 ₃
The overlapping length of the 1.2 mm, to constitute a thickness of the dielectric layer 1 ₁ 0.2 mm, the thickness of the dielectric layer 1 ₅ as 1.2 mm.

Here, the electrode 6₁~ 6_Three, 61₁~ 6
1_Three, 7₁~ 7_Three, 71₁~ 71_Three, 8 ₁~ 8_Three, 81
₁~ 81_ThreeLayered dielectric filter
For the filter, the center frequency is 1900 MHz and the bandwidth is 75
MHz. The product of the second embodiment of the above configuration with the above specifications
The center frequency of a layered dielectric filter is 1500 MHz,
The bandwidth was 75 MHz and the insertion loss was 2.5 dB.
Further, the electrode 6₁~ 6_ThreeOnly the electrical from the ground electrode 2
, The center frequency changes to 1540MHz
However, there was almost no change in bandwidth.

Instead of the electrodes 6 _{1 to} 6 ₃ , the electrodes 61 ₁ to 61 ₁
61 ₃ when electrically disconnected from the ground electrode 2 were also the same. The electrode 7 _1-7 in addition to the electrode ₆₁ through _{3
When 3} was electrically disconnected from the ground electrode 2, the center frequency was changed to 1560 MHz, and the bandwidth was hardly changed. As is clear from this, the center frequency can be largely adjusted according to the number of electrodes electrically disconnected from the ground electrode 2.

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

FIG. 8 is a schematic developed view showing the configuration of the third embodiment of the present invention.

The dielectric layer 1 ₁₁ is deposited on dielectric layer 1 ₁₀
To the surface of a first embodiment of the resonant element 3 ₁ to 3 ₃ same plurality of resonant elements with 3 _{11-3 13.} Further, the dielectric layer 1 ₁₁
The other end extending to the end portion is electrically connected to the earth electrode 2 and electrode 4 ₁₁ the other end opposite to the resonance element 3 ₁₁ apart a predetermined distance from the other end of the resonant element 3 _11, 4 ₁₂ ,
4 _13, 4 ₁₄ to parallel form on the surface of the dielectric layer 1 _11,
Electrode 4 ₂₁ facing similarly to the resonance element 3 _11, 4 _22, 4 _23,
4 parallel ₂₄ formed in the surface of the dielectric layer 1 _11, formed on the surface of the opposite to the resonance element ₃₁₃ electrode 4 _31, 4 _32, 4 _33, 4 ₃₄ dielectric layer 1 ₁₁ in parallel And the resonance elements 3 _{11 to} 3 ₁₃
The resonance elements 3 ₁₁ to
A comb-line type filter is constructed by utilizing the fact that 3 ₁₃ is inductively coupled.

Dielectric layer 1₁₁Dielectric layer 1 laminated thereon₁₂
A dielectric layer 1 on one surface of₁₂On the input side across
Child 3₁₁And one end of the dielectric layer 1₁₂One end of
Section and is electrically connected to an input terminal (not shown).
And the resonance element 3₁₁Input power so that
Pole 5₁₁Is formed, and the dielectric layer 1₁₂Invite to one surface of
Electric body layer 1₁₂Resonance element 3 on the output side with₁₂Part of
One end of the dielectric layer 1 ₁₂Extending to the other end of
Not electrically connected to the output terminal and the resonance element
3₁₃Output electrode 5 so as to be substantially orthogonal to₁₂To form

[0036] On the dielectric layer 1 _12, by stacking the dielectric layer 1 ₁₃ earth electrode 2 is formed on the surface, the dielectric layer 1 ₁₀ to 1
₁₃ was constructed integrally, the dielectric layer 1 ₁₀ to 1 ₁₃ configured to integrally
The ground electrode 2 is applied to the front and rear surfaces of the substrate and the side surface excluding the input terminal portion and the output terminal portion (not shown).

[0037] Also in the third embodiment constructed as described above, the adjustment of the resonance frequency of the resonant element 3 _{11-3 13,} electrodes 4 _{11-4 14,} 4 _{21-4 24,} 4 _{31-4 34} for one or more of, by peeling the portion of the corresponding earth electrode 2, electrode 4 _{11-4 14,} 4 _{21-4 24,} 4 _{31-4 34}
One or more of the above are electrically disconnected from the ground electrode 2. Electrode 4 _{11-4 14} in this embodiment, 4 _21-4
24, 4 _{31-4 34} because is divided smaller, electrode 4 ₁₁
To 4 _14, 4 ₂₁ to 4 _24, 4 ₃₁ capacitance between the resonant element 3 _{11-3 13} corresponding to each to 4 ₃₄ are small, fine adjustment of the resonant frequency of the resonant element 3 _{11-3 13} Can be performed.

In the laminated dielectric filter of the third embodiment,
Here, each resonance element 3₁₁~ 3₁₃Width 0.8mm, resonance
Element 3₁₁And 3₁₂And the resonance element 3₁₁And 3₁₃With
The spacing is 1.2 mm, the resonance element 3₁₁~ 3₁₃5mm
And each electrode 4₁₁~ 4₁₄, 4 _{twenty one}~ 4_{twenty four}, 4₃₁~ 4₃₄Each of
0.125mm width, each electrode 4₁₁~ 4₁₄Set the interval between 0.
1 mm, each electrode 4_{twenty one}~ 4_{twenty four}Distance of each electrode is 0.1mm
4₃₁~ 4₃₄The distance between them is 0.1 mm, and the dielectric layer 1_Tenand
1₁₁Thickness of 1.3 mm, dielectric layer 1₁₁And 1₁₂Thickness
When the height is 0.2 mm, the center frequency is 1700 MH
z. The electrodes 4ij (i = 1, 2, 3, j = 1, 2,
3) by disconnecting one of them from the ground electrode 2
The heart frequency increased by 20 MHz.

[0039] In the third embodiment, the electrodes 4 ₁₁ -
4 _14, 4 ₂₁ to 4 _24, 4 ₃₁ to 4 ₃₄ is not limited to the resonant element 3 _{11-3 13} same dielectric layer and may be provided on the the resonance element different dielectric layers, thus However, the above-mentioned effects are obtained. Further, the third embodiment can be combined with the first and second embodiments by dividing a part of the electrodes in the first and second embodiments as in the third embodiment. . By combining the third embodiment with the first and second embodiments described above, coarse adjustment can be performed by peeling off the portion of the ground electrode 2 corresponding to the electrodes of the first and second embodiments that are not divided, Fine adjustment can be performed by peeling off the ground electrode 2 corresponding to the divided electrode of the third embodiment.

Next, a modification of the third embodiment will be described. This modified example is different from the third embodiment in that the dielectric layer 1
_12, as shown in FIG. 9 (a), the surface of the dielectric layer 1 _12,
In addition to the input electrode 5 ₁₁ and the output electrode 5 _12, electrodes 4 _{11-4 14,} 4 _{22-4 24,} 4 paired sandwiching the dielectric layer 1 ₁₂
Respectively _{31-4 34} opposite each other, one end is dielectric layer 1 ₂
Connected extends to the other end to the ground electrode 2 of electrically, and the other end to form an electrode 11 _1, 11 _2, 11 ₃ overlapping another each the resonant element 3 _{11-3 13.}

Further, the dielectric layer 1_TenIs shown in Fig. 9 (b).
U, dielectric layer 1_TenDielectric layer 1 on the surface of₁₁Between
Pole part 4₁₁~ 4₁₄, 4_{twenty one}~ 4_{twenty four}, 4₃₁~ 4₃₄To each
One end faces each other, and one end is a dielectric layer 1₁To the other end of
Extending to be electrically connected to the ground electrode 2, and
Resonant element 3₁₁~ 3₁₃Electrodes 12 overlapping each other₁, 1
2 _Two, 12_ThreeTo form For others,
The configuration is the same as that of the third embodiment.

The modification of the third embodiment described above is the same as the case where the first or second embodiment is combined with the third embodiment. As described above, the coarse adjustment and the fine adjustment can be performed. it is obvious.

In each of the above embodiments and modified examples, the case where the arrangement of the resonance elements is of the comb line type has been described. However, the present invention can also be applied to the case of the interdigital type.

[0044]

As explained above, according to the present invention, one end is electrically connected to the ground electrode, one or more resonance elements constituting the laminated dielectric filter, and one end is electrically connected to the ground electrode. In order to adjust the resonance frequency of the opposing resonance element, the electric connection with the ground electrode is cut off in accordance with the adjustment amount of the resonance frequency. Since one or more electrodes are provided in the dielectric, the capacitance existing between the resonance element and the electrode is in a state of being connected in parallel to the parallel resonance circuit formed by the resonance element, and the electrical connection is established from the ground electrode. The capacitance connected in parallel to the parallel resonance circuit changes depending on the number of electrodes that are cut off, the resonance frequency of the resonance element is adjusted, and the frequency response of the multilayer dielectric filter corresponds to the deviation of the center frequency from the target value. Must There is an effect that can be adjusted in such frequency.

Further, according to the present invention, since the adjustment of the resonance frequency can be performed by shaving the portion of the ground electrode including one end portion of the electrode, there is an effect that the adjustment can be easily performed, and the size of the electrode facing the resonance element can be easily adjusted. By setting the number and the number, fine adjustment and coarse adjustment can be performed, and there is an effect that fine adjustment can be performed.

[Brief description of the drawings]

FIG. 1 is a schematic developed view showing the configuration of a first embodiment of the present invention.

FIG. 2 is a perspective view of the first embodiment of the present invention.

FIG. 3 is a plan view showing the configuration of the main part of the first embodiment of the present invention, and a cross-sectional view showing the configuration of the main part of the first and second embodiments of the present invention.

FIG. 4 is an electrical equivalent circuit diagram of the first embodiment of the present invention.

5A and 5B are a side view and an electrical equivalent circuit diagram for explaining the resonance frequency adjustment according to the first embodiment of the present invention.

FIG. 6 is a cross-sectional view illustrating a configuration of a first modification of the second embodiment of the present invention.

FIG. 7 is a sectional view showing a configuration of a second modification of the second embodiment of the present invention.

FIG. 8 is a schematic developed view showing the configuration of a third embodiment of the present invention.

FIG. 9 is a schematic developed view showing a part of a modification of the third embodiment of the present invention.

FIG. 10 is an explanatory view, a sectional view, and a plan view showing a configuration of a conventional example.

[Explanation of symbols]

1 ₁ to 1 _5, 1 ₁₀ to 1 ₁₃ ... dielectric layer 2 ... ground electrode 3 ₁ to 3 _3, 3 _{11-3 13} ... resonant element 41 _{to 3,} 4 _{11-4 14,} 4 _{21-4 24} , 4 _{31-4 34} ... electrodes 5 _1, 5 ₁₁ ... input electrode 5 _2, 5 ₁₂ ... output electrode ₆₁ through _3, 6 _{11-6 13} ... electrode 7 _{1-7 3,} 7 _{11-7 13} … Electrode 8 ₁ to 8 ₃ , 8 ₁₁ to 8 ₁₃ … Electrode 9 ₁ … Input terminal 9 ₂ … Output terminal 11 _{1 to} 11 ₃ , 12 _{1 to} 12 ₃ ,.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H01P 1/203 H01P 1/205 H01P 7/08

Claims (1)

(57) [Claims] 1. One or more resonant elements, one end of a strip line of which is electrically connected to a ground electrode to form a laminated dielectric filter, and a plurality of dielectric layers laminated on one main surface of the resonant element. A plurality of electrodes respectively formed in a layer, and a plurality of electrodes are provided in a dielectric, and the plurality of electrodes are opposed to the open ends of the corresponding resonance element, and are in plane with the resonance element with a dielectric layer interposed therebetween. Wherein the electrical connection with the ground electrode is cut off in accordance with the adjustment amount of the resonance frequency in order to adjust the resonance frequency of the opposed resonance element. filter.