JP2004015430A - Two-port type nonreciprocal circuit element and communication apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a two-port type nonreciprocal circuit element capable of suppressing a stray capacitance caused between an earth pattern of a printed circuit board and a metallic case when mounted on the printed circuit board or the like. <P>SOLUTION: The two-port type nonreciprocal circuit element 1 is roughly provided with: the metallic case comprising a metal-made upper case 4 and a metal-made lower case 8; a permanent magnet 9; a center electrode assembly 13 comprising a ferrite 20, and center electrodes 21, 22; and a layered board 30. The laminated substrates 30 is placed on a bottom 8a of the metal-made lower case 8 and a ground electrode placed on the lower side of the laminated substrates 30 is connected and fixed to the bottom 8a by solder 80. Thus, an earth port 16 is electrically and easily connected to the bottom 8a. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a two-port non-reciprocal circuit device, particularly to a two-port non-reciprocal circuit device such as an isolator used in a microwave band and a communication device.
[0002]
[Prior art]
Generally, an isolator has a function of passing a signal only in a transmission direction and preventing transmission in a reverse direction, and is used in a transmission circuit unit of a mobile communication device such as a car phone or a mobile phone.
[0003]
For example, a known isolator of this type is disclosed in Japanese Patent Application Laid-Open No. 9-232818. FIG. 12 is an external perspective view of the two-port isolator, and FIG. 13 is an electrical equivalent circuit diagram. The isolator 300 is disposed in a metal case formed by joining a metal lower case 301 and a metal upper case 302 to a permanent magnet (not shown), a ferrite 320, and main surfaces of the ferrite 320. The first center electrode 321 and the second center electrode 322, matching capacitors C1 and C2, and a resistor R are housed therein. The first and second center electrodes 321 and 322, the matching capacitors C1 and C2, and the resistor R are built in the multilayer substrate 330, and an input port 314, an output port 315, and an earth port 316 are provided on the surface of the multilayer substrate 330. I have.
[0004]
Although not shown, on the lower surface of the laminated substrate 330, a common capacitor electrode on the output port 315 side of the matching capacitors C1 and C2 is provided. This common capacitor electrode is electrically connected to the lower metal case 301.
[0005]
When this two-port isolator 300 is mounted on a printed circuit board 350 such as a mobile phone as shown in FIG. 12, a slight gap is generated between the metal lower case 301 and the ground pattern G of the printed circuit board 350. . This is because the bottom surfaces of the feet on both sides of the laminated substrate 330 are made of metal so that the ports 314 to 316 provided on the laminated substrate 330 can be securely soldered to the signal lines 340 and 341 and the ground pattern G of the printed substrate 350. This is because it is designed to slightly protrude from the bottom surface of the lower case 301.
[0006]
[Problems to be solved by the invention]
However, in the conventional two-port isolator 300, the metal case (the lower metal case 301) was not connected to the ground port 316 and was in an electrically floating state. Therefore, a stray capacitance is generated between the metal case and the ground pattern G of the printed circuit board.
[0007]
This stray capacitance C3 is connected in an equivalent circuit as shown in FIG. 13, and is substantially equivalent to an increase in the capacitance of the matching capacitor C2. For this reason, there is a problem that the characteristics of the isolator 300 deviate, and the characteristics vary depending on the shape of the ground pattern G and the gap size between the ground pattern G and the metal case.
[0008]
SUMMARY OF THE INVENTION It is an object of the present invention to provide a two-port type non-reciprocal circuit device and a communication device capable of suppressing stray capacitance generated between the printed circuit board and a ground pattern when the device is mounted on a printed circuit board or the like.
[0009]
Means and action for solving the problem
In order to achieve the above object, a two-port non-reciprocal circuit device according to the present invention comprises:
(A) a permanent magnet;
(B) a ferrite to which a DC magnetic field is applied by a permanent magnet;
(C) a first center electrode disposed on the main surface of the ferrite, one end of which is electrically connected to the first input / output port, and the other end of which is electrically connected to the second input / output port;
(D) disposed on the main surface of the ferrite so as to intersect with the first center electrode in an electrically insulated state, one end of which is electrically connected to the second input / output port, and the other end of which is electrically connected to the ground port. A second central electrode,
(E) a parallel RC circuit comprising a first matching capacitor and a resistor, electrically connected between the first input / output port and the second input / output port;
(F) a second matching capacitor electrically connected between the second input / output port and the earth port;
(G) a metal case surrounding the permanent magnet, the ferrite, and the first and second center electrodes,
(H) electrically connecting the metal case to the earth port;
It is characterized by.
[0010]
More specifically, the first and second matching capacitors are built in a multilayer substrate formed by stacking a plurality of dielectric layers and capacitor electrodes, and ferrite is disposed on the upper surface of the multilayer substrate. Then, the metal case is joined to the earth-side capacitor electrode of the second matching capacitor provided on the lower surface of the multilayer substrate, and the metal case is electrically connected to the earth port.
[0011]
When the two-port type non-reciprocal circuit element is mounted on a printed circuit board or the like with the above configuration, the metal case is grounded and has the same potential as the ground-side capacitor electrode of the second matching capacitor and the ground pattern of the printed circuit board. For this reason, a stray capacitance generated between the metal case and the ground pattern of the printed board is less likely to occur. Further, by providing a plurality of ground ports, the metal case can be grounded more reliably and stably.
[0012]
Also, the ground-side capacitor electrode of the second matching capacitor may be arranged in a plurality of layers, or the capacitor electrode on the side electrically connected to the first input / output port of the first matching capacitor may be arranged in a plurality of layers. By doing so, the capacitance of the second matching capacitor and the first matching capacitor can be increased. Furthermore, by arranging the first matching capacitor and the second matching capacitor at different positions in the stacking direction of the multilayer substrate, the first and second matching capacitors are formed on different layers. Therefore, the capacitor electrodes that can be formed per layer can have a large area, the capacitance can be large, and the first and second matching capacitors that effectively utilize the area of the laminated substrate can be obtained.
[0013]
Also, one of the capacitor electrodes of the first matching capacitor is provided near the surface layer of the multilayer substrate and in the same layer as one of the ground-side capacitor electrodes of the second matching capacitor. This facilitates trimming adjustment of the first and second matching capacitors.
[0014]
Both ends of the first center electrode and the second center electrode extend on the lower surface of the ferrite, and one end of the first center electrode on the side electrically connected to the second input / output port and the second center electrode. One end on the side electrically connected to the second input / output port is electrically connected to the lower surface of the ferrite, and the other ends of the first and second center electrodes are separated from each other. With the above configuration, the number of electrical connections between the center electrode and the laminated substrate is reduced, and low cost and high reliability can be realized.
[0015]
Further, the communication device according to the present invention includes the above-described two-port type non-reciprocal circuit device, so that performance and reliability are improved.
[0016]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of a two-port type non-reciprocal circuit device and a communication device according to the present invention will be described with reference to the accompanying drawings.
[0017]
[First Embodiment, FIGS. 1 to 8]
FIG. 1 is an exploded perspective view of one embodiment of a two-port non-reciprocal circuit device according to the present invention. The two-port type non-reciprocal circuit device 1 is a lumped constant type isolator. As shown in FIG. 1, the two-port isolator 1 generally includes a metal case including a metal upper case 4 and a metal lower case 8, a permanent magnet 9, a ferrite 20, and center electrodes 21 and 22. And a laminated substrate 30.
[0018]
The metal upper case 4 has a substantially box shape and includes an upper portion 4a and four side portions 4b. The lower metal case 8 includes left and right sides 8b and a bottom 8a. In order to form a magnetic circuit, the metal upper case 4 and the metal lower case 8 are formed of, for example, a material made of a ferromagnetic material such as soft iron, and their surfaces are plated with Ag or Cu.
[0019]
The center electrode assembly 13 orthogonally intersects two sets of first and second center electrodes 21 and 22 on the upper surface of the disc-shaped microwave ferrite 20 with an insulating layer (not shown) interposed. Has been placed. In the first embodiment, the center electrodes 21 and 22 are constituted by two lines. Both ends 21a, 21b, 22a, 22b of the first center electrode 21 and the second center electrode 22 extend on the lower surface of the ferrite 20, and the ends 21a to 22b are separated from each other.
[0020]
The center electrodes 21 and 22 may be wound around the ferrite 20 using a copper foil, or may be formed by printing a silver paste on or inside the ferrite 20. Alternatively, it may be formed of a laminated substrate as described in JP-A-9-232818. However, since the printing has higher positional accuracy of the center electrodes 21 and 22, the connection with the laminated substrate 30 is stabilized. In particular, when the connection is made with minute center electrode connection electrodes 51 to 54 (described later) as in this case, printing and forming the center electrodes 21 and 22 improves reliability and workability.
[0021]
As shown in FIG. 2, the laminated substrate 30 has connection electrodes 51 to 54 for the center electrode, a dielectric sheet 41 provided with a capacitor electrode 55, a relay electrode 56, and a resistor R on the back surface, and a capacitor electrode 57 provided on the back surface. And a dielectric sheet 43 provided with a ground electrode 58 on the back surface, a dielectric sheet 45 provided with the input port 14, the output port 15, and the earth port 16, and the like.
[0022]
This laminated substrate 30 is manufactured as follows. That is, the dielectric sheets 41 to 45 have Al ₂ O ₃ as a main component and include SiO ₂ , SrO, CaO, PbO, Na ₂ O, K ₂ O, MgO, BaO, CeO ₂ , and B ₂ O ₃ . It is made of a low-temperature sintered dielectric material containing one or more types as subcomponents.
[0023]
Furthermore, shrinkage suppression sheets 46 and 47 are formed which do not bake under the firing conditions of the laminated substrate 30 (especially a firing temperature of 1000 ° C. or less) and suppress the firing shrinkage of the laminated substrate 30 in the substrate plane direction (XY direction). The material of the shrinkage suppression sheets 46 and 47 is a mixed material of alumina powder and stabilized zirconia powder. The thickness of the sheets 41 to 47 is about 10 μm to 200 μm.
[0024]
The electrodes 51 to 58 are formed on the back surfaces of the sheets 41 to 43 and 46 by a method such as pattern printing. As a material of the electrodes 51 to 58, Ag, Cu, Ag-Pd or the like which has a low resistivity and can be co-fired with the dielectric sheets 41 to 45 is used. The surfaces of the electrodes 51 to 58 are plated with Au using Ni plating as a base. The Ni plating increases the bonding strength between the Ag and Au plating of the electrodes 51 to 58. The Au plating improves the solder wettability and has a high conductivity, so that the isolator 1 can have low loss. The thickness of the electrodes 51 to 58 is about 2 μm to 20 μm. Usually, the thickness of the electrodes 51 to 58 and the like is set to be twice or more the skin thickness.
[0025]
The resistor R is formed on the back surface of the dielectric sheet 41 by a method such as pattern printing. Cermet, carbon, ruthenium, or the like is used as a material of the resistor R. The resistor R may be formed by printing on the upper surface of the laminated substrate 30 or may be formed by a chip resistor.
[0026]
The via holes 60, the side via holes 65, and the ports 14 to 16 are formed by forming via holes in advance on the dielectric sheets 41 to 45 by laser processing or punching processing, and then filling the via holes with a conductive paste. Is done.
[0027]
The capacitor electrode 57 opposes the capacitor electrode 55 with the dielectric sheet 42 interposed therebetween to constitute a matching capacitor C1. Further, the capacitor electrode 57 is opposed to the ground electrode 58 with the dielectric sheet 43 interposed therebetween to constitute a matching capacitor C2. The matching capacitors C1 and C2 and the resistor R, together with the electrodes 51 to 54, the ports 14 to 16 and the via holes 60 and 65, form an electric circuit inside the multilayer substrate 30.
[0028]
The above-described dielectric sheets 41 to 45 are laminated, and further sandwiched between the upper and lower sides of the laminated body of the dielectric sheets 41 to 45 by the shrinkage suppressing sheets 46 and 47, and then fired. As a result, a sintered body is obtained, and thereafter, the unsintered shrinkage suppressing material is removed by an ultrasonic cleaning method or a wet honing method to obtain a laminated substrate 30 as shown in FIG.
[0029]
An input port 14, an output port 15, and an earth port 16 are provided at both ends of the laminated substrate 30, respectively. The input port 14 is electrically connected to a capacitor electrode 55, and the output port 15 is electrically connected to a capacitor electrode 57. The ground port 16 is electrically connected to the ground electrode 58.
[0030]
Note that the laminated substrate 30 is usually created in a motherboard state. Half cut grooves are formed on the mother board at a predetermined pitch, and the mother board is folded along the half cut grooves to obtain a laminated substrate 30 having a desired size from the mother board. Alternatively, the laminated board 30 having a desired size may be cut out by cutting the motherboard with a dicer, a laser, or the like.
[0031]
The multilayer substrate 30 thus obtained has matching capacitors C1 and C2 and a resistor R inside. The trimming of the matching capacitor C1 is performed before connecting the matching capacitors C1 and C2 and the center electrodes 21 and 22. In other words, the laminated substrate 30 is trimmed (eliminated) with the inner (second layer) capacitor electrode 55 together with the surface dielectric material in a single state. For the trimming, for example, a laser of a fundamental wave, a second harmonic, and a third harmonic of a cutting machine or YAG is used. If a laser is used, quick and accurate processing can be obtained. The trimming may be efficiently performed on the laminated substrate 30 in a motherboard state.
[0032]
As described above, since the capacitor electrode 55 close to the upper surface of the multilayer substrate 30 is used as the trimming capacitor electrode, the thickness of the dielectric layer removed during trimming can be minimized. In addition, since the number of electrodes that obstruct trimming is reduced (only the connection electrodes 51 to 54 in the case of the first embodiment), the area of the capacitor electrode that can be trimmed is widened, and the capacitance adjustment range can be widened.
[0033]
The laminated substrate 30 also has a built-in resistor R. Like the matching capacitor C1, the resistor R can be adjusted in resistance value by trimming with the surface dielectric. Since the resistance value of the resistor R increases when the width of the resistor R is reduced even at one location, the resistor R is cut to some extent in the width direction.
[0034]
The above components are assembled as follows. That is, as shown in FIG. 1, the permanent magnet 9 is fixed to the ceiling of the metal upper case 4 by an adhesive. The respective ends 21 a to 22 b of the center electrodes 21 and 22 of the center electrode assembly 13 are electrically connected to the center electrode connection electrodes 51 to 54 formed on the surface of the laminated substrate 30 by solder 80. The center electrode assembly 13 is mounted on the laminated substrate 30. The center electrodes 21 and 22 and the center electrode connection electrodes 51 to 54 may be efficiently soldered to the laminated substrate 30 in a motherboard state.
[0035]
The laminated substrate 30 is placed on the bottom 8 a of the lower metal case 8, and the ground electrode 58 disposed on the lower surface of the laminated substrate 30 is connected and fixed to the bottom 8 a by the solder 80. Thus, the earth port 16 is electrically easily connected to the bottom 8a.
[0036]
The metal lower case 8 and the metal upper case 4 form a metal case by joining the respective side portions 8b and 4b with solder or the like, and also function as a yoke. That is, the metal case forms a magnetic path surrounding the permanent magnet 9, the center electrode assembly 13, and the laminated substrate 30. The permanent magnet 9 applies a DC magnetic field to the ferrite 20.
[0037]
Thus, the two-port isolator 1 shown in FIG. 3 is obtained. FIG. 4 is an electrical equivalent circuit diagram of the isolator 1. One end 21 a of the first center electrode 21 is electrically connected to the input port 14, and the other end 21 b is electrically connected to the output port 15. One end 22 a of the second center electrode 22 is electrically connected to the output port 15, and the other end 22 b is electrically connected to the ground port 16. The parallel RC circuit including the matching capacitor C1 and the resistor R is electrically connected between the input port 14 and the output port 15. The matching capacitor C2 is electrically connected between the output port 15 and the earth port 16.
[0038]
In the two-port isolator 1 having the above configuration, the bottom portion 8a (metal case) of the metal lower case 8 and the ground port 16 are electrically connected to each other, as shown in FIG. When mounted on the printed circuit board 350, the metal case is grounded and has the same potential as the ground pattern G of the printed circuit board 350. For this reason, the stray capacitance generated between the metal case and the ground pattern G can be suppressed, and the two-port isolator 1 with small characteristic shift and characteristic variation when mounted on the printed circuit board 350 can be obtained.
[0039]
Here, as shown in FIG. 3, when this two-port isolator 1 is mounted on a printed circuit board 350 such as a mobile phone, a slight gap is formed between the lower metal case 8 and the ground pattern G of the printed circuit board 350. Occurs. This is because the bottom surfaces of the legs on both sides of the laminated board 30 are made of metal so that the ports 14 to 16 provided on the laminated board 30 can be securely soldered to the signal lines 340 and 341 and the ground pattern G of the printed board 350. This is because it is designed to slightly protrude from the bottom surface of the lower case 8. In addition, an insulating layer is provided on the electrode at the soldered portion to prevent solder flow. For this reason, even if the terminal portion does not protrude, a gap corresponding to the insulating layer is generated between the ground pattern G of the printed circuit board 350 and the isolator 1.
[0040]
FIGS. 5, 6, 7, and 8 show the input reflection loss characteristic, output reflection loss characteristic, isolation characteristic, and insertion loss of the two-port isolator 1 having a size of 4 mm long × 4 mm wide × 1.7 mm high, respectively. 5 is a graph showing characteristics (see a solid line). Even after the two-port isolator 1 was mounted on the printed circuit board 350, these characteristics hardly changed. On the other hand, when a conventional two-port isolator 300 (size: 4 mm long × 4 mm wide × 1.7 mm high) in which the metal case shown in FIG. 13 and the earth port 316 are not electrically connected is mounted on the printed circuit board 350. Had a characteristic shift (see dotted line). At this time, the gap between the metal case and the ground pattern G of the printed circuit board 350 was 0.1 mm. That is, this is a characteristic when the thickness is 0.1 mm and a floating capacitance (approximately 1.4 pF) having a relative dielectric constant of 1 (air) is formed.
[0041]
In the first embodiment, four ground ports 16 are provided. Thereby, the metal case can be more reliably and stably grounded, and the mounting strength of the isolator 1 can be improved. In addition, since the matching capacitors C1 and C2 are arranged vertically in the stacking direction of the laminated substrate 30, the electrodes 55, 57, and 58 that can be formed per layer can have a large area. Therefore, the capacitance of each of the matching capacitors C1 and C2 can be increased.
[0042]
[Second Embodiment, FIGS. 9 and 10]
The two-port isolator 1A shown in FIG. 9 is the same as the two-port isolator 1 of the first embodiment except for the center electrode assembly 13A and the laminated substrate 30A.
[0043]
In the center electrode assembly 13A, the first and second center electrodes 21 and 22 are arranged on the upper surface of the ferrite 20 so as to intersect with each other with an insulating layer (not shown) interposed therebetween. Both ends 21 a to 22 b of the center electrodes 21 and 22 extend on the lower surface of the ferrite 20. An end 21b of the first center electrode 21 on the side electrically connected to the output port 15 and an end 22a of the second center electrode 22 on the side electrically connected to the input port 14 are formed by ferrite. 20 are electrically connected to each other. The remaining ends 21a and 22b of the center electrodes 21 and 22 are separated from each other.
[0044]
As shown in FIG. 10, the laminated substrate 30A has connection electrodes 51 to 53 for a center electrode, a dielectric sheet 41a provided with a capacitor electrode 55a, a ground electrode 59a, a resistor R and the like on the back surface, and a capacitor electrode 57a provided on the back surface. The dielectric sheet 42a provided, the dielectric sheet 41b provided with the capacitor electrode 55b and the ground electrode 59b on the back surface, the dielectric sheet 42b provided with the capacitor electrode 57b on the back surface, and the dielectric material provided with the ground electrode 58 on the back surface. It is composed of a sheet 43 and a dielectric sheet 45 provided with the input port 14, the output port 15, and the earth port 16.
[0045]
The capacitor electrodes 57a and 57b constitute a multi-stage matching capacitor C1 facing the capacitor electrodes 55a and 55b with the dielectric sheets 42a, 41b and 42b interposed therebetween. Further, the capacitor electrodes 57a, 57b are opposed to the ground electrodes 59a, 59b, 58 with the dielectric sheets 42a, 41b, 42b, 43 interposed therebetween to form a multi-stage matching capacitor C2. Thereby, matching capacitors C1 and C2 having a large capacitance can be obtained. Further, if the capacitance is the same, the electrode area can be reduced, so that the conductor loss of the capacitor can be reduced and the loss of the isolator 1A can be reduced.
[0046]
The ground electrode (earth-side capacitor electrode) 59a of the matching capacitor C2 is located near the surface layer of the multilayer substrate 30A, and the capacitor electrode of the matching capacitor C1 (the capacitor electrode electrically connected to the input port 14) 55a. Are arranged in the same layer (second layer). Therefore, the capacitance of the matching capacitor C2 can be adjusted by trimming the ground electrode 59a together with the surface dielectric.
[0047]
The center electrode assembly 13A is mounted on the laminated substrate 30A. The number of connection electrodes 51 to 53 for the center electrode formed on the surface layer of the laminated substrate 30A is small, so that the number of via holes 60 formed on the laminated substrate 30A and the number of connection locations can be reduced, and the manufacturing cost can be reduced. it can.
[0048]
[Third embodiment, FIG. 11]
In the third embodiment, a mobile phone will be described as an example of the communication device according to the present invention.
[0049]
FIG. 11 is an electric circuit block diagram of the RF portion of the mobile phone 220. In FIG. 11, 222 is an antenna element, 223 is a duplexer, 231 is a transmitting isolator, 232 is a transmitting amplifier, 233 is a band-pass filter for transmitting stages, 234 is a transmitting mixer, 235 is a receiving amplifier, and 236 is a receiving amplifier. The reception-side interstage band-pass filter, 237 is a reception-side mixer, 238 is a voltage-controlled oscillator (VCO), and 239 is a local band-pass filter.
[0050]
Here, the lumped constant type isolators 1 and 1A of the first and second embodiments can be used as the transmission side isolator 231. By mounting these isolators, a highly reliable mobile phone with improved electrical characteristics can be realized.
[0051]
It should be noted that the present invention is not limited to the above embodiment, and can be variously modified within the scope of the gist.
[0052]
【The invention's effect】
As apparent from the above description, according to the present invention, since the metal case is electrically connected to the ground port, when the two-port type non-reciprocal circuit element is mounted on a printed circuit board or the like, the metal case is grounded, It has the same potential as the ground-side capacitor electrode of the second matching capacitor and the ground pattern of the printed circuit board. For this reason, the stray capacitance generated between the metal case and the ground pattern of the printed board can be suppressed, and the characteristic shift and the characteristic variation when mounted on the printed board can be reduced. As a result, it is possible to obtain a high-performance, highly-reliable and small two-port type non-reciprocal circuit device or communication device.
[Brief description of the drawings]
FIG. 1 is an exploded perspective view showing an embodiment of a two-port non-reciprocal circuit device according to the present invention.
FIG. 2 is an exploded perspective view of the laminated substrate shown in FIG.
FIG. 3 is an external perspective view of the two-port nonreciprocal circuit device shown in FIG.
FIG. 4 is an electrical equivalent circuit diagram of the two-port nonreciprocal circuit device shown in FIG.
FIG. 5 is a graph showing input return loss characteristics.
FIG. 6 is a graph showing output return loss characteristics.
FIG. 7 is a graph showing isolation characteristics.
FIG. 8 is a graph showing insertion loss characteristics.
FIG. 9 is an exploded perspective view showing another embodiment of the two-port type non-reciprocal circuit device according to the present invention.
10 is an exploded perspective view of the laminated substrate shown in FIG.
FIG. 11 is an electric circuit block diagram of a communication device according to the present invention.
FIG. 12 is an external perspective view showing a conventional two-port type non-reciprocal circuit device.
13 is an electrical equivalent circuit diagram of the two-port nonreciprocal circuit device shown in FIG.
[Explanation of symbols]
1, 1A Lumped constant type isolator 4 Metal upper case 8 Metal lower case 9 Permanent magnet 13, 13A Center electrode assembly 14 Input port 15 Output port 16 Earth port 20 Ferrite 21 1st center electrode 22 ... 2nd center electrode 21a, 21b, 22a, 22b ... End 30, 30A ... Laminated substrates 41-45, 41a, 41b, 42a, 42b ... Dielectric sheets 55, 57, 55a, 55b, 57a , 57b ... capacitor electrodes 58, 59a, 59b ... ground electrode 220 ... mobile phones C1, C2 ... matching capacitors R ... resistors

Claims (10)

A permanent magnet,
A ferrite to which a DC magnetic field is applied by the permanent magnet;
A first center electrode disposed on the main surface of the ferrite, one end of which is electrically connected to the first input / output port, and the other end of which is electrically connected to the second input / output port;
The ferrite is disposed on the main surface of the ferrite so as to intersect with the first center electrode in an electrically insulated state, one end is electrically connected to the second input / output port, and the other end is electrically connected to the ground port. A second center electrode;
A parallel RC circuit electrically connected between the first input / output port and the second input / output port, the parallel RC circuit including a first matching capacitor and a resistor;
A second matching capacitor electrically connected between the second input / output port and the ground port;
A metal case surrounding the permanent magnet, the ferrite, and the first and second center electrodes,
Electrically connecting the metal case to the ground port,
A two-port type non-reciprocal circuit device characterized by the above-mentioned. The said 1st and 2nd matching capacitor | condenser is built in the laminated board | substrate comprised by laminating | stacking a several dielectric layer and a capacitor electrode, The said ferrite is arrange | positioned on the upper surface of this laminated board | substrate, The claim 2. The two-port type non-reciprocal circuit device according to 1. The two-port irreversible according to claim 2, wherein the metal case is joined to and electrically connected to a ground-side capacitor electrode of the second matching capacitor provided on the lower surface of the multilayer substrate. Circuit element. The two-port type non-reciprocal circuit device according to claim 2, wherein the second matching capacitor has a plurality of ground-side capacitor electrodes. The two port according to claim 2, wherein the first matching capacitor has a plurality of capacitor electrodes on a side electrically connected to the first input / output port. 6. Type non-reciprocal circuit device. The two port according to claim 2, wherein the first matching capacitor and the second matching capacitor are arranged at different positions in a stacking direction of the multilayer substrate. Type non-reciprocal circuit device. 3. The capacitor of claim 1, wherein one of the capacitor electrodes of the first matching capacitor is provided near a surface layer of the multilayer substrate and in the same layer as one of the ground-side capacitor electrodes of the second matching capacitor. The two-port type non-reciprocal circuit device according to claim 5. Both ends of the first center electrode and the second center electrode extend on the lower surface of the ferrite, and one end of the first center electrode on a side electrically connected to a second input / output port is connected to the first center electrode. One end of the two center electrodes on the side electrically connected to the second input / output port is electrically connected on the lower surface of the ferrite, and the other ends of the first and second center electrodes are mutually connected. The two-port type non-reciprocal circuit device according to claim 1, wherein the two-port type non-reciprocal circuit device is separated. The two-port type non-reciprocal circuit device according to any one of claims 1 to 8, wherein a plurality of the earth ports are provided. A communication device comprising the two-port non-reciprocal circuit device according to claim 1.

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