JP2007300605A - Nonreciprocal circuit element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a nonreciprocal circuit element capable of forming a capacitance element to be used as an impedance adjusting means without enlarging a laminated substrate. <P>SOLUTION: A third capacitance element connected between a first input/output port and a ground is formed on the laminated substrate constituted of a dielectric layer and an electrode pattern, and on a bottom surface of the laminated substrate, an input terminal electrode, an output terminal electrode and a first ground electrode are positioned. The third capacitance element is formed by confronting a second ground terminal provided within the laminated substrate through the dielectric layer for the input terminal electrode, and the first ground electrode and the second ground electrode are connected by a via-hole. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a nonreciprocal circuit device having a nonreciprocal transmission characteristic with respect to a high-frequency signal, and more particularly to a nonreciprocal circuit device that is used in a mobile communication system such as a mobile phone and generally called an isolator.

  Non-reciprocal circuit elements such as isolators are often used in mobile communication devices that use frequency bands from several hundred MHz to several tens of GHz, that is, PHS (Personal Handy Phone) base stations and mobile phone terminals. Has been. For example, the isolator is disposed between the power amplifier and the antenna in the transmission stage of the mobile communication device, and prevents backflow of unnecessary signals to the power amplifier and stabilizes the impedance on the load side of the power amplifier. Therefore, the isolator is required to have excellent insertion loss characteristics, reflection loss characteristics, and isolation characteristics.

  FIG. 7 is an equivalent circuit of the two-terminal pair isolator disclosed in Patent Document 1, and FIG. 8 is an exploded perspective view showing each component. The two-terminal pair isolator is provided between the first input / output port P1 and the second input / output port P2, and includes a first center conductor 21 that forms the first inductance element L1, and the first center conductor 21 and the A second central conductor 22 that forms a second inductance element L2, and a first input / output port P1 and a second input / output. Provided between the port P2, and provided between the first inductance element L1 and the first capacitance element Ci and the resistance element R constituting the first parallel resonant circuit, between the second input / output port P2 and the ground, 2 inductance elements L2 and a second capacitance element Cf constituting a second parallel resonant circuit.

  When a high frequency signal propagates from the first input / output port P1 to the second input / output port P2, the first parallel resonant circuit between the first input / output port P1 and the second input / output port P2 does not resonate, Since the second parallel resonant circuit resonates, the transmission loss is small (excellent insertion loss characteristics). The current flowing backward from the second input / output port P2 to the first input / output port P1 is absorbed by the resistance element R between the first input / output port P1 and the second input / output port P2.

  As shown in FIG. 8, the two-terminal pair isolator 1 includes a case (upper case 4 and lower case 8) made of a ferromagnetic metal such as soft iron, a permanent magnet 9, and a microwave ferrite so as to constitute a magnetic circuit. 20 and a central conductor assembly 13 including central conductors 21 and 22 and a multilayer substrate 30 on which the central conductor assembly 13 is mounted. The center conductor assembly 13 includes a disk-shaped microwave ferrite 20 and first and second center conductors 21 and 22 arranged on the upper surface thereof so as to be orthogonal to each other via an insulating layer (not shown). ing. The first and second center conductors 21 and 22 are each composed of two lines, and both ends of each line extend to the lower surface of the microwave ferrite 20 in a state of being separated from each other.

  The laminated substrate 30 is formed with a first capacitance element Ci that forms a first parallel resonance circuit, a second capacitance element Cf that forms a second parallel resonance circuit, and a resistance element R. The laminated substrate 30 includes electrodes 51 to 54 connected to the end portions of the center conductors 21 and 22, and one end portion of the first center conductor 21 is connected to the input external electrode 14 via the electrode 51. The other end portion of the first center conductor 21 is connected to the output external electrode 15 through the electrode 54. One end of the second central conductor 22 is connected to the output external electrode 15 through an electrode 53. The other end of the second center conductor 22 is connected to the ground external electrode 16 via the electrode 52.

  In order to obtain a two-terminal pair isolator with excellent electrical characteristics, various manufacturing variations such as inductance caused by connection lines connecting reactance elements and stray capacitance caused by interference between electrode patterns are considered. There is a need. In the two-terminal pair isolator, an unnecessary reactance component may be connected to the first and second parallel resonant circuits. As a result, the input impedance of the two-terminal pair isolator deviates from a desired value. As a result, there is a problem of deterioration of insertion loss characteristics and isolation characteristics.

In consideration of the unnecessary reactance component, it is possible to determine the inductance and the capacitance constituting the first and second parallel resonance times. However, because the first and second center conductors 21 and 22 are connected to each other even if the width and interval of the lines constituting the first and second center conductors 21 and 22 are simply changed. The inductance values of the first and second inductance elements L1 and L2 change together, and it is difficult to independently adjust the input impedances of the first input / output port P1 and the second input / output port P2, respectively. In some cases, it is difficult to obtain the optimum matching condition. In particular, the deviation of the input impedance of the first input / output port P1 is not preferable because it causes an increase in insertion loss.
In order to solve such a problem, the present inventors have proposed in Patent Document 2 that an impedance adjusting means is disposed between the first input / output port P1 and the first inductance element.
JP-A-2004-88743 JP 2006-50543 A

It is disclosed that the impedance adjusting means is composed of a reactance element and is formed by an electrode pattern formed on a multilayer substrate or mounted on the multilayer substrate as a chip component. This method is effective and effective for adjusting the impedance. However, in particular, when a capacitance element is provided, it is desired that the electrode pattern formation area and the thickness of the multilayer substrate be reduced due to the miniaturization of the multilayer substrate. In some cases, the electrode pattern could not be formed to obtain the capacitance value. Moreover, although it is necessary to measure whether the formed capacitance element has a desired capacitance value, it may be difficult due to the influence of the first capacitance element Ci and the second capacitance element Cf.
Accordingly, a first object of the present invention is to provide a non-reciprocal circuit device capable of forming a capacitance device used as impedance adjusting means without increasing the size of a laminated substrate. It is a second object of the present invention to make it possible to measure the capacitance value of the capacitance element without being affected by the first capacitance element Ci and the second capacitance element Cf.

The first invention includes a first inductance element connected between the first input / output port and the second input / output port, a second inductance element connected between the second input / output port and the ground, A first capacitance element connected between the first input / output port and the second input / output port and constituting a parallel resonance circuit with the first inductance element, and between the second input / output port and the ground. A second capacitance element connected to form a parallel resonance circuit with the second inductance element; a third capacitance element connected between the first input / output port and ground; the first input / output port; A non-reciprocal circuit device comprising a resistance element connected between the second input / output port,
The third capacitance element is formed on a multilayer substrate including a dielectric layer and an electrode pattern, and an input terminal electrode, an output terminal electrode, and a first grant electrode are provided on a bottom surface of the multilayer substrate, and the input terminal electrode The third capacitance element is formed by facing a second grant electrode provided inside the multilayer substrate through a dielectric layer, and the first grant electrode and the second grant electrode are connected by a via hole. This is a non-reciprocal circuit device.

  In the present invention, it is preferable that a first capacitance element electrode connected to the input terminal electrode is provided inside the multilayer substrate, and the second grant electrode is opposed to the dielectric substrate through the dielectric layer.

The second invention includes a first inductance element connected between the first input / output port and the second input / output port, a second inductance element connected between the second input / output port and the ground, A first capacitance element connected between the first input / output port and the second input / output port and constituting a parallel resonance circuit with the first inductance element, and between the second input / output port and the ground. A second capacitance element connected to form a parallel resonance circuit with the second inductance element; a third capacitance element connected between the first input / output port and ground; the first input / output port; A non-reciprocal circuit device comprising a resistance element connected between the second input / output port,
The third capacitance element is formed on a multilayer substrate including a dielectric layer and an electrode pattern, and an input terminal electrode, an output terminal electrode, a first grant electrode, and a third ground electrode are provided on the bottom surface of the multilayer substrate. In the laminated substrate, a second grant electrode and a first capacitance element electrode connected to the input terminal electrode are provided, and the second grant electrode and the first capacitance element electrode are opposed to each other through a dielectric layer. Thus, the third capacitance element is formed, and the second grant electrode and the third grant electrode are connected by a via hole.

  In the first or second invention, a fourth ground electrode and a first capacitance element electrode connected to the output terminal electrode are provided in the laminated body in order from the lower surface side of the laminated body, and are opposed to each other through the dielectric layer. Then, it is preferable that a second capacitance element is formed and the fourth ground electrode and the first grant electrode are connected by a via hole.

  In addition, a mounting electrode is provided on the upper surface of the multilayer body, and a central conductor assembly including a plurality of central conductors arranged in microwave ferrite is mounted on the mounting electrode, and the central conductor and the first inductance element are mounted. A second inductance element is preferably formed.

(First embodiment)
FIG. 1 is an external perspective view of a non-reciprocal circuit device according to an embodiment of the invention, and FIG. 2 is a top view thereof. 3 shows an equivalent circuit of the non-reciprocal circuit element, FIG. 4 is an exploded perspective view of the non-reciprocal circuit element, and FIG. 5 is an exploded perspective view of a multilayer substrate used for the non-reciprocal circuit element.

  The nonreciprocal circuit element includes a first inductance element L1, a second inductance element L2, a first inductance element L1, a first capacitance element Ci constituting a first parallel resonant circuit, and a second inductance. A second capacitance element Cf constituting the element L2 and the second parallel resonant circuit; a third capacitance element Cin connected between the first input / output port P1 and the ground; the first input / output port P1; And a resistance element R connected between the two input / output ports P2.

  The nonreciprocal circuit device 1 includes a microwave ferrite 20 and a center conductor disposed so as to wrap the microwave ferrite 20 (consisting of a first center conductor 21 and a second center conductor 22 that intersect with each other in an electrically insulated state on the microwave ferrite 20). A center conductor assembly 13 having a capacitor Ci and Cf formed therein, electrode patterns 35, 40, 45 and 60, input / output terminal electrodes IN and OUT, and a first ground electrode GND1 formed on the surface, and a chip A multilayer substrate 30 mounted with a resistor R, a lower case 8 that accommodates the multilayer substrate 30, a permanent magnet 9 that supplies a DC magnetic field to the microwave ferrite 20, and a permanent magnet 9 that is accommodated and engaged with the lower case 8 And an upper case 4.

In the center conductor assembly 13, for example, a first center conductor 21 and a second center conductor 22 are arranged on the surface of a rectangular microwave ferrite 20 so as to intersect via an insulating layer (not shown). . In the present embodiment, the first central conductor 21 and the second central conductor 22 are orthogonal (the crossing angle is 90 °), but cases where the crossing angle is other than 90 ° are also within the scope of the present invention. In general, the first center conductor 21 and the second center conductor 22 only need to intersect within an angle range of 80 ° to 110 °.
Such a central conductor can be formed, for example, by stamping from a copper plate having a thickness of 30 μm. In order to reduce loss due to the skin effect at high frequencies, it is preferable to apply silver plating with a thickness of 1 to 4 μm to the copper plate. In the present embodiment, the first center conductor 21 is composed of three parallel conductors (lines), and the second center conductor 22 is composed of one conductor (line). With such a configuration, the inductance of the first center conductor 21 is formed smaller than the inductance of the second center conductor 22, and the impedance is adjusted.
Instead of integrally forming the first center conductor 21 and the second center conductor 22 from a single copper plate, they may be formed from separate copper plates. Moreover, you may form the 1st center conductor 21 and the 2nd center conductor 22 on both surfaces of flexible heat-resistant insulating sheets, such as a polyimide, by the printing method or the etching method. Further, the first central conductor 21 and the second central conductor 22 may be printed on the microwave ferrite 20. Thus, the form of the first center conductor 21 and the second center conductor 22 is not limited.

  The microwave ferrite 20 may be a magnetic material that functions as a non-reciprocal circuit element with respect to a DC magnetic field from the permanent magnet 9. As a preferable magnetic material, ferrite having a garnet structure such as yttrium-iron-garnet (YIG) can be mentioned, but ferrite having a spinel structure such as Ni-based ferrite can also be used depending on the operating frequency. In the case of YIG, part of Y may be replaced with Gd, Ca, V, etc., and part of Fe may be replaced with Al, Ga, etc. Further, when the first and second center conductors 21 and 22 are formed by printing, a predetermined amount of Bi may be added so that the first and second center conductors 21 and 22 can be fired simultaneously with the electrode pattern constituting the center conductor.

The permanent magnet 9 for applying a DC magnetic field to the center conductor assembly 13 is fixed to the inner wall surface of the upper case 4 with an adhesive or the like. The permanent magnet 9 is preferably a ferrite magnet [for example, (Sr / Ba) O.nFe ₂ O ₃ ] from the viewpoint of cost and compatibility of temperature characteristics with the microwave ferrite 20. Furthermore, (Sr / Ba) RO.n (FeM) ₂ O ₃ [R is at least one element of rare earth elements including Y, and a part of Sr and / or Ba is substituted, and M is Co, Mn, Ni And at least one element selected from the group consisting of Zn, a part of Fe is substituted], has a magnetoplumbite-type crystal structure, has an R element and / or The ferrite magnet added in the pulverization step after calcination in the state where the M element is in a compound has a high magnetic flux density, so that the nonreciprocal circuit element can be reduced in size and thickness. As for the magnetic properties of the ferrite magnet, the residual magnetic flux density Br is 430 mT or more, particularly 440 mT or more, the coercive force iHc is 340 kA / m or more, and the maximum energy product (BH) max is 35 kJ / m ³ or more. preferable.

  The laminated substrate 30 is produced by a known LTCC (Low Temperature Co-fireable Ceramics) method. A conductive paste mainly composed of Ag, Cu or the like is printed on a dielectric sheet made of ceramic that can be fired at a low temperature to form a desired conductor pattern, and the obtained dielectric sheets with a conductor pattern are laminated. Obtained by firing. Thereby, the multilayer substrate 30 in which a plurality of capacitance elements are integrated is obtained. By using low-temperature sintered ceramics for the laminated substrate 50, a metal having a high conductivity such as Ag, Cu, Au or the like can be used for the electrode pattern. By using a dielectric material having a high Q value and using an electrode in which loss due to electric resistance is suppressed, a non-reciprocal circuit device with extremely small loss can be obtained.

  Mounting electrodes 35, 40, 45, and 50 are disposed on the dielectric sheet S1, a first capacitance element electrode 36 is formed on the dielectric sheet S2, and a second capacitance element electrode is formed on the dielectric sheet S3. 37, the first capacitance element electrode 38 is formed on the dielectric sheet S4, and the second ground electrode GND2 and the fourth ground electrode GND4 are formed on the dielectric sheet S5. On the back surface of the multilayer substrate 30, an input terminal electrode IN and an output terminal electrode OUT are disposed with the first ground electrode GND1 interposed therebetween.

The electrode patterns on the dielectric sheets S1 to S5 are appropriately electrically connected through via holes (indicated by black circles in the figure) filled with a conductive paste. The mounting electrode 60 formed on the surface of the multilayer substrate 30 is connected to the input terminal electrode IN through the via hole and the second capacitance element electrode 37 of the dielectric sheet S3. The mounting electrodes 40 and 45 are electrically connected to each other and output via the via hole, the first capacitance element electrode 36 of the dielectric sheet S2, and the first capacitance element electrode 38 of the dielectric sheet S4. Connected to the terminal electrode OUT. The electrode pattern 35 is connected to the first ground electrode GND1 through the via hole and the second ground electrode GND2. The electrode patterns 36, 37, and 38 form a first capacitance element Ci, and the electrode pattern 38 and the fourth ground electrode GND4 of the dielectric sheet S5 form a second capacitance element Cf.
The second ground electrode GND2 of the dielectric sheet S5 forms the third capacitance element Cin for impedance matching with the second capacitance element electrode 37 and the input terminal electrode IN of the dielectric sheet S3. . In this way, by forming the input terminal electrode IN as a capacitor electrode pattern for forming the third capacitance element Cin, the third capacitance element Cin having a desired capacitance value is formed without increasing the size of the multilayer substrate. It became possible.

The multilayer substrate 30 is accommodated in the lower case 8, and the input terminal electrode IN and the output terminal electrode OUT of the multilayer substrate 30 are respectively connected to the exposed end of the input terminal and the exposed end of the output terminal (not shown) of the lower case 8. Solder. The first ground electrode GND1 at the bottom of the multilayer substrate 30 is soldered to the frame bottom of the lower case 8. The lower case 8 and the upper case 4 engaged therewith are formed of a ferromagnetic material such as soft iron and function as a magnetic yoke that forms a magnetic circuit surrounding the permanent magnet 40, the central conductor assembly 30, and the multilayer substrate 50. . The lower case 8 includes a resin wall, and holds the terminals IN and OUT and is integrated with the lower case 8.
The upper and lower cases 4 and 8 are preferably formed with a plating layer made of at least one metal selected from the group consisting of Ag, Au, Cu and Al, or an alloy thereof. The electric resistivity of the plating layer is preferably 5.5 μΩcm or less, more preferably 3 μΩcm or less, and most preferably 1.8 μΩcm or less. The thickness of the plating layer is preferably 0.5 to 25 μm, more preferably 0.5 to 10 μm, and most preferably 1 to 8 μm. With such a configuration, it is possible to reduce the loss by suppressing the mutual interference with the external circuit.
As described above, a non-reciprocal circuit device having a small size and excellent electrical characteristics could be obtained.

(Second Embodiment)
The nonreciprocal circuit device of this embodiment uses a laminated substrate that can accurately measure the capacitance value of the third capacitance device. Since there are many configurations in common with the non-reciprocal circuit device of the first embodiment, the following description will be focused on the differences.
FIG. 6 is an exploded perspective view of the multilayer substrate used in the nonreciprocal circuit device of this embodiment. This laminated substrate is also produced by a known LTCC method. Mounting electrodes 35, 40, 45, 60, and 65 are disposed on the dielectric sheet S1, a fifth ground electrode GND5 is formed on the dielectric sheet S2, and an electrode for the first capacitance element is formed on the dielectric sheet S3. 36, the second capacitance element electrode 37 is formed on the dielectric sheet S4, the first capacitance element electrode 38 and the second ground electrode GND2 are formed on the dielectric sheet S5, and the dielectric sheet S6 is formed on the dielectric sheet S6. A fourth ground electrode GND4 is formed. On the back surface of the multilayer substrate 30, the input terminal electrode IN and the output terminal electrode OUT are disposed substantially in the middle with the first ground electrode GND 1 interposed therebetween. Further, a third ground electrode GND3 is formed electrically separated from the first ground electrode GND1.

The electrode patterns on the dielectric sheets S1 to S6 are electrically connected as appropriate through via holes (indicated by black circles in the figure) filled with a conductive paste. The mounting electrodes 60 and 65 formed on the surface of the multilayer substrate 30 are connected to the input terminal electrode IN through the via hole and the second capacitance element electrode 37 of the dielectric sheet S4. The mounting electrodes 40 and 45 are electrically connected to each other and output via the via hole, the first capacitance element electrode 36 of the dielectric sheet S3, and the first capacitance element electrode 38 of the dielectric sheet S5. Connected to the terminal electrode OUT. The electrode pattern 35 is connected to the first ground electrode GND1 through the via hole, the fifth ground electrode GND5, and the fourth ground electrode GND4. The second ground electrode GND2 of the dielectric sheet S4 is connected to a third ground electrode GND3 provided on the back surface of the multilayer substrate through a via hole. The electrode patterns 36, 37, and 38 form a first capacitance element Ci, and the electrode pattern 36 and the fifth ground electrode GND5, and the electrode pattern 38 and the fourth ground electrode GND4 form a second capacitance element Cf. .
The second ground electrode GND2 and the second capacitance element electrode 37 of the dielectric sheet S4 form a third capacitance element Cin for impedance matching. Thus, by dividing the ground electrode on the back surface of the multilayer substrate, the first and second capacitance elements Ci and Cf and the third capacitance element Cin are electrically separated. In the state of the laminated substrate, the first capacitance element Ci is between the input terminal electrode IN and the output terminal electrode OUT, and the second capacitance element Cf is between the output terminal electrode OUT and the first ground electrode GND1. Alternatively, the capacitance value of the third capacitance element Cin can be accurately measured between 65 and the third ground electrode GND3.

  After mounting the resistive element R between the mounting electrodes 45 and 60 of the multilayer substrate and further mounting the central conductor assembly 30, the multilayer substrate is accommodated in the lower case, and the input terminal electrode IN and the output of the multilayer substrate are accommodated. The terminal electrode OUT is soldered to the exposed end of the input terminal of the lower case and the exposed end of the output terminal. Note that the exposed end of the input terminal and the exposed end of the output terminal of the lower case are formed at positions corresponding to the input terminal electrode IN and the output terminal electrode OUT of the multilayer substrate. The first ground electrode GND1 and the third ground electrode GND3 at the bottom of the multilayer substrate are soldered to the bottom of the frame of the lower case to be electrically connected to each other.

  According to the present invention, the capacitance element used as the impedance adjusting means can be formed without increasing the size of the laminated substrate, and the capacitance value of the capacitance element is influenced by the first capacitance element Ci and the second capacitance element Cf. It is possible to obtain a non-reciprocal circuit element that can be measured without being received, can be formed without increasing the size of the laminated substrate, is small, and has excellent electrical characteristics.

1 is an external perspective view of a non-reciprocal circuit device according to an embodiment of the present invention. It is a top view of the nonreciprocal circuit device by one embodiment of this invention. It is an equivalent circuit diagram of the nonreciprocal circuit device according to one embodiment of the present invention. It is a disassembled perspective view of the nonreciprocal circuit device by one embodiment of this invention. It is a disassembled perspective view of the multilayer substrate used for the nonreciprocal circuit device by one embodiment of this invention. It is a disassembled perspective view of the multilayer substrate used for the nonreciprocal circuit device by other embodiment of this invention. It is an equivalent circuit diagram of the conventional nonreciprocal circuit device. It is a disassembled perspective view of the conventional nonreciprocal circuit device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Nonreciprocal circuit element 4 Upper case 8 Lower case 9 Permanent magnet 13 Center conductor assembly 20 Microwave ferrite 21, 22 Center conductor 30 Laminated substrate 35, 60, 40, 45 Surface electrode pattern

Claims (5)

A first inductance element connected between the first input / output port and the second input / output port; a second inductance element connected between the second input / output port and the ground; and the first input / output port. Connected between the first input / output port and the second input / output port, connected between the first inductance element and the first capacitance element forming a parallel resonant circuit, and between the second input / output port and the ground. A second capacitance element that forms a parallel resonant circuit with the inductance element, a third capacitance element connected between the first input / output port and the ground, the first input / output port, and the second input / output port; A non-reciprocal circuit device comprising a resistance element connected between
The third capacitance element is formed on a multilayer substrate including a dielectric layer and an electrode pattern, and an input terminal electrode, an output terminal electrode, and a first grant electrode are provided on a bottom surface of the multilayer substrate, and the input terminal electrode The third capacitance element is formed by facing a second grant electrode provided inside the multilayer substrate through a dielectric layer, and the first grant electrode and the second grant electrode are connected by a via hole. A nonreciprocal circuit device characterized by the above.   2. The nonreciprocal device according to claim 1, wherein a first capacitance element electrode connected to the input terminal electrode is provided inside the multilayer substrate, and the second grant electrode is opposed to the second substrate through a dielectric layer. Circuit element. A first inductance element connected between the first input / output port and the second input / output port; a second inductance element connected between the second input / output port and the ground; and the first input / output port. Connected between the first input / output port and the second input / output port, connected between the first inductance element and the first capacitance element forming a parallel resonant circuit, and between the second input / output port and the ground. A second capacitance element that forms a parallel resonant circuit with the inductance element, a third capacitance element connected between the first input / output port and the ground, the first input / output port, and the second input / output port; A non-reciprocal circuit device comprising a resistance element connected between
The third capacitance element is formed on a multilayer substrate including a dielectric layer and an electrode pattern, and an input terminal electrode, an output terminal electrode, a first grant electrode, and a third ground electrode are provided on the bottom surface of the multilayer substrate. In the laminated substrate, a second grant electrode and a first capacitance element electrode connected to the input terminal electrode are provided, and the second grant electrode and the first capacitance element electrode are opposed to each other through a dielectric layer. The non-reciprocal circuit device is characterized in that the third capacitance element is formed and the second grant electrode and the third grant electrode are connected by a via hole.   In the multilayer body, a fourth ground electrode and a first capacitance element electrode connected to the output terminal electrode are provided in order from the lower surface side of the multilayer body, and a second capacitance element is formed facing the dielectric layer. 4. The nonreciprocal circuit device according to claim 1, wherein the fourth ground electrode and the first grant electrode are connected by a via hole.   A mounting electrode is provided on an upper surface of the multilayer body, and a central conductor assembly including a plurality of central conductors arranged in microwave ferrite is mounted on the mounting electrode, and a first inductance is formed by the central conductor. The nonreciprocal circuit device according to any one of claims 1 to 4, wherein an element and a second inductance element are formed.

Images