JPH06204712A - Irreversible circuit element - Google Patents

Abstract

PURPOSE:To secure a grounding characteristic and to surely keep an earth potential without influence of a magnetic and electric characteristic of a yoke by forming upper and lower yokes as separate bodies and providing the independent earth terminal of the yokes. CONSTITUTION:Upper lower yokes 5,6 are formed separately and independent earth terminals 81, 82 are provided in addition to the yokes 5, 6. Thus, the yokes 5, 6 are surely kept to have an earth potential without substantial influence of the magnetic characteristic and the electric characteristic of the yokes 5, 6 by using the earth terminals 81, 82. For example, even when the electric resistance of the yokes 5, 6 formed small and thin is increased, the yokes 5, 6 are surely kept to have an earth potential because of a low electric resistance of the earth terminals 81, 82 independently of the increase.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a nonreciprocal circuit device having a nonreciprocal transmission characteristic, and more specifically, a nonreciprocal circuit used as an isolator or a circulator in a communication system such as a car phone, a mobile phone, a cordless phone. Regarding the device.

[0002]

2. Description of the Related Art Non-reciprocal circuit devices of this kind are disclosed, for example, in Japanese Patent Laid-Open No. 260605/1990 and 246022/1990.
Those described in Japanese Patent Publications and the like are known. The non-reciprocal circuit device described in these known documents includes a non-reciprocal circuit device body having a support substrate, a magnetic body, a shield plate and a permanent magnet, and a yoke. The non-reciprocal circuit device body has a magnetic body arranged on one side or both sides of three strip conductors symmetrically arranged at a crossing angle of 120 degrees on a support substrate, and the magnetic body is covered with a shield plate from the outside. Apply a DC magnetic field with a permanent magnet. The yoke is made of a soft magnetic material, constitutes a magnetic path for a magnetic field generated by a permanent magnet, is used as a fixture for fixing a case that mechanically supports the nonreciprocal circuit element body, and also serves as a ground terminal.

[0003]

As described above, in the conventional non-reciprocal circuit device, the yoke forming the magnetic path further includes
Since it also serves as a ground terminal, when the yoke is thinned in order to meet the demands for downsizing and thinning, the electric resistance of the yoke increases and the grounding characteristics of the ground terminal deteriorate. When the material is changed in order to reduce the electric resistance to improve the grounding characteristics, the magnetic characteristics of the magnetic path may deteriorate and the efficiency may decrease.

Therefore, an object of the present invention is to ensure the necessary grounding characteristics and to reliably keep the yoke at the ground potential without being substantially affected by the magnetic and electrical characteristics of the yoke. A non-reciprocal circuit device is provided.

[0005]

In order to solve the above-mentioned problems, according to the present invention, the upper and lower yokes are provided separately, and a ground terminal is provided separately from the yoke.

[0006]

Since the upper and lower yokes are separate and the ground terminal is provided separately from the yoke, unlike the conventional non-reciprocal circuit device, the effect of the magnetic and electrical characteristics of the yoke is practically exerted. It is possible to secure the necessary grounding characteristics and to reliably maintain the yoke at the ground potential without receiving it. For example, even if the electric resistance of the yoke increases due to the thinning of the yoke in order to meet the demands for downsizing and thinning, regardless of this, the low electric resistance of the ground terminal ensures that the yoke is at the ground potential. Can be kept at Even if a magnetic material having a large electric resistance is used to improve the magnetic characteristics of the yoke, the yoke can be reliably kept at the ground potential by the electric characteristics of the ground terminal without being affected by the magnetic material. .

[0007]

1 is an exploded perspective view of a non-reciprocal circuit device according to the present invention, FIG. 2 is a plan view of the non-reciprocal circuit device, and FIG. 3 is A of FIG.
3 is a front sectional view taken along the line 3-A3, and FIG. 4 is a front sectional view taken along the line A4-A4 in FIG. In the figure, 1 is a support substrate, 2 is a magnetic material, 3 is a ground conductor, 4 is a permanent magnet, 5 and 6 are yokes, 7 is a capacitor, 8 is a case, and 9
Is a resistance plate.

The support substrate 1 includes a plurality of strip conductors and has a ground electrode which is electrically connected to the ground terminals (81, 82). As shown in FIG. 5 or 6, the support substrate 1 has three strip conductors (11, 12, 13).
Intersect with each other at an angle of 120 degrees, the input / output electrodes (151, 152) serving as conduction paths for the input / output terminals (83, 84) on the front side, and the ground terminals (81, 8) on the rear side.
2) Grounding electrodes (145, 14) as a conduction path
6). In the strip conductor 11, the divided piece 110 is arranged on the front surface of the substrate 14 and the divided piece 111 is arranged on the back surface, and the divided piece 110 and the divided piece 111 are connected to each other by using penetrating conductors (11a, 11b). There is. Similarly,
The strip conductor 12 is formed on the surface of the substrate 14 by a divided piece 120.
Is arranged on the back surface by dividing the divided piece 121 into two pieces, and the divided piece 1
20 and the divided piece 121 are connected by using through conductors (12a, 12b). Also for the strip conductor 13, the divided piece 130 is provided on the front surface of the substrate 14 and the divided piece 1 is provided on the back surface.
31 is divided into two and arranged, and the divided pieces 130 and 13 are arranged.
1 and 1 are made conductive by using through conductors (13a, 13b). These through conductors (11a, 11b, 12a, 1
2b, 13a, 13b) and through conductors (141, 14)
2, 143, 144) can be formed by plating.

The magnetic body 2 is made of a ferrimagnetic material such as YIG (yttrium iron garnet), and two magnetic bodies 2 are arranged at the upper and lower positions facing the strip conductors (11, 12, 13).

As for the ground conductor 3, with respect to the upper magnetic body 2, the conductor film 7 coated on the inner peripheral surface of the hole 10 of the capacitor 7 is used.
4 and a shield plate 3a disposed above the magnetic body 2, and the lower magnetic body 2 is composed of a shield plate 3b that electrically shields the lower magnetic body 2. In this way, the ground conductor 3 is arranged so as to cover both magnetic bodies 2. Both shield plates (3a, 3b) are thin copper plates plated with silver. Three projecting pieces 31 to 33 are provided upright on the periphery of the lower shield plate 3b.

The surface of the permanent magnet 4 is covered with the conductor film 41, and the permanent magnet 4 is arranged both outside the upper shield plate and the lower shield plate as the ground conductor 3, and both are electrically connected to the ground conductor 3. A DC magnetic field is applied to the magnetic body 2. As the permanent magnet 4, an insulating permanent magnet, for example, a ferrite magnet can be used. The conductor film 41 can be formed, for example, by plating the surface of the permanent magnet 4 with copper or the like having high conductivity. Even when a metal magnet other than the ferrite magnet is used as the permanent magnet 4, the surface of the metal magnet can be plated and used.

The lower yoke 5 and the upper yoke 6 cover the support substrate 1, the magnetic body 2, the ground conductor 3 and the permanent magnet 4 so as to be electrically connected to the permanent magnet 4. York 5
For example, a material obtained by coating an insulating resin on a material in which iron is plated with silver except at least a portion that is conductively connected to the permanent magnet 4 is used. Fluororesin is suitable as the insulating resin. Since the fluororesin has a good heat dissipation property, it can help to realize a compact and high-power nonreciprocal circuit device. As the yoke 6, a thin iron plate plated with nickel is used.

Fluorine resin is suitable as the insulating resin attached to the yoke 5. Since the fluororesin has a good heat dissipation property, it can help to realize a compact and high-power nonreciprocal circuit device. The yoke 5 is not coated with an insulating resin,
It can also be used as a ground terminal.

The capacitor 7 is made of a glass base fluororesin copper clad laminate or the like, and has three dielectric layers (71).
1, 712, 713) and dielectric layers (711, 71).
2, 713) have electrodes for capacitance formation on both main surfaces facing each other, and are laminated with each other to form a laminated body. The laminate has a ground electrode (76
0, 770) and the hole 10 in the plane. The magnetic body 2 is inserted into the hole 10. Hole 10
Is entirely covered with the conductor film 74.
Is electrically connected to both ground electrodes (760, 770). The conductor film 74 can be formed by plating the inner wall surface of the hole 10, vacuum deposition, or sputtering.

The case 8 is made of an insulating material such as an insulating resin. As shown in FIGS. 7 and 8, the case 8 has a ground terminal 81 on the surface on which the support substrate 1 is placed.
And an earth electrode 812 connected to the earth terminal 82, an input / output electrode 813 connected to the input / output terminal 83, and an input / output electrode 814 connected to the input / output terminal 84. Ground electrode (811, 81
2) are the electrodes (145, 14) of the supporting substrate 1, respectively.
6) via the earth conductor projecting pieces (32, 33) (see FIG. 6).

The resistor plate 9 has a resistor 9a and electrodes 9b and 9c sandwiching the resistor 9a, and is arranged on one side of the upper surface of the case 8. One of the electrodes 9b is connected to the ground electrode 146 on the support substrate 1 and the ground electrode 811 of the case 8.
And the other is connected to the ground electrode 14 on the support substrate 1.
5 and the grounding electrode 812 of the case 8. The electrode 9c is connected to the terminating electrode 131 on the support substrate 1. Therefore, with this resistor 9, two resistors 9C are connected in parallel with each other, so that a circuit element capable of passing a larger current can be obtained. The resistor plate 9 uses, for example, a resistor material such as ruthenium oxide (RuO) on an alumina substrate as the resistor 9a, and silver-palladium (AgPd) as the electrodes 9b and 9c.
It is formed by a printing technique using an electrode material such as.

Electrodes (9b, 9c) without the resistance plate 9
A circulator can be obtained by connecting the strip conductor 3 terminated by (4) to the newly provided terminal 85 via the electrode 815.

In assembling, the lower permanent magnet 4 is mounted on the yoke 5, then the resistance plate 9 is arranged on one side of the upper surface of the case 8, and then the lower magnetic body 2 is projected. Three
The lower ground conductor 3 arranged between 1, 32 and 33 is inserted into the hole 86 of the case 8. Next, the support substrate 1 is attached to the case 8
Then, the capacitor 7 is placed on the supporting substrate 1, the upper magnetic body 2 is inserted into the hole 10 of the capacitor 7, and the upper earth conductor 3 is covered thereon. Subsequently, the upper permanent magnet 4 is arranged so as to apply a magnetic field perpendicularly to the upper magnetic body 2, and the yoke 6 is further covered thereover, and the stopper 51 of the yoke 5 and the stopper receiving portion of the yoke 6 are arranged. The case 8 is fixed by fitting with 61.

The nonreciprocal circuit device is, in this embodiment,
Although the magnetic body 2 and the permanent magnet 4 are arranged on both sides of the strip conductor (11, 12, 13), the magnetic body and the permanent magnet may be arranged only on one surface of the strip conductor. Needless to say.

As mentioned above, the upper and lower yokes (5, 6)
Since the ground terminals (81, 82) are provided separately from the yoke (5, 6) independently of each other, the effect of the magnetic characteristics and the electrical characteristics of the yoke (5, 6) has It is possible to reliably keep the yokes 5 and 6 at the ground potential by using the ground terminals (81 and 82) without receiving them. For example, even if the electric resistance of the yokes 5 and 6 increases due to the thinning of the yokes 5 and 6 in order to meet the demands for downsizing and thinning, the low resistance of the ground terminals 81 and 82 is irrelevant regardless of this. The electric resistance allows the yokes 5 and 6 to be reliably kept at the ground potential. Further, in order to improve the magnetic characteristics of the yokes 5 and 6, even if a magnetic material having a large electric resistance is used for the yokes 5 and 6, the ground terminals 81 and 82 are not affected by it.
Due to the electric characteristics of the yokes 5, the yokes 5 and 6 can be reliably kept at the ground potential.

Moreover, by keeping the yokes (5, 6) at the ground potential, it is possible to reduce the intermodulation distortion generated in the product incorporating this circuit element.

Next, the electrode pattern of each dielectric layer (711, 712, 713) of the above-mentioned capacitor 7 will be described in detail.

FIG. 9 is a plan view of the capacitor 7. In the figure, the first dielectric layer 711 is made of a glass base fluororesin or the like, and the ground electrode 760 is formed on the surface thereof. 751 to 753 are penetrating conductors that penetrate the first dielectric layer 711 formed by plating or the like.

FIG. 10 is a sectional view taken along line A10-A10 of FIG. In the figure, the second dielectric layer 712 is made of glass base fluororesin or the like and has three capacitor electrodes (761, 762, 763). The capacitor electrodes (761, 762, 763) are led out to the surface side of the first dielectric layer 711 by through conductors 751 to 753 (see FIGS. 8 and 9).

FIG. 11 is a sectional view taken along line A11-A11 of FIG. In the figure, the third dielectric layer 713 is made of glass base fluororesin or the like, and is made up of three capacitor electrodes (7
64, 765, 766). The capacitor electrode 764 includes the capacitor electrode 761 and the second dielectric layer 712.
The two capacitors face each other with the capacitor in between and form a capacitor. The capacitor electrode 765 includes a capacitor electrode 762 and a second dielectric layer 712.
The two capacitors face each other with the capacitor in between and form a capacitor. The capacitor electrode 766 includes the capacitor electrode 763 and the second dielectric layer 712.
The two capacitors face each other with the capacitor in between and form a capacitor.

FIG. 12 is a bottom view of the capacitor 7. In the figure, the electrodes (770) formed on the bottom surface are connected to the ground electrodes (771, 772) as the conduction paths of the ground terminals (81, 82) and the input / output terminals (83, 84) as the conduction paths. It has output electrodes (773, 774). The grounding electrodes (771, 772) are the supporting substrate 1
Is electrically connected to the ground electrodes (145, 146). The input / output electrodes (773, 774) are electrically connected to the input / output electrodes (151, 152) provided at the ends of the strip conductors (11, 12) of the support substrate 1.

FIG. 13 is a development view used to show an electrically equivalent circuit of the capacitor 7 having the structure shown in FIGS. 9 to 12. a, b, c are through conductors 751, 7
The terminals formed by 52 and 753 are shown.
An inter-terminal capacitance C11 formed by the capacitor electrode 761 and the capacitor electrode 764 is formed between the terminals a and b, an inter-terminal capacitance C12 formed by the capacitor electrode 762 and the capacitor electrode 765 is formed between the terminals b and c, and an inter-terminal capacitance Ca is formed. An inter-terminal capacitance C13 is formed by the capacitor electrode 763 and the capacitor electrode 766. Also, the ground electrode (76
0,770) and capacitor electrodes (761,766),
Ground capacitors C01, C02, C03 are formed between (762, 764) and (763, 765), respectively.

FIG. 14 shows an equivalent circuit diagram of an isolator using the capacitor 7 shown in FIGS. 9 to 12, in which an inter-terminal capacitance C11 is connected between the terminals a and b, and an inter-terminal capacitance between the terminals b and c. C12 is connected, and the capacitance between terminals C1 is
It is possible to obtain a circuit in which the ground capacitors C01, C02, and C03 are connected to the terminals a, b, and c, respectively, in addition to the connection of No. 3.

In the present embodiment, the capacitor 7 includes a plurality of dielectric layers (711, 712, 713) and is laminated on each other to form a laminated body, and the laminated body has a hole 10 in the center. Since the magnetic body 2 is inserted into the hole 10, the nonreciprocal circuit device can be made small and thin. Moreover, the positioning of the magnetic body 2 becomes easy.

The capacitor 7 has a plurality of dielectric layers (71
1, 712, 713) and dielectric layers (711, 71).
2, 713) have opposite main surfaces and are laminated to each other to form a laminated body, the area reduction for forming the capacitor due to the provision of the holes 10 is reduced in the thickness direction. It can be supplemented by a stack of 7. Therefore, the non-reciprocal circuit device can be downsized and thinned.

In the capacitor 7, since the entire inner peripheral surface of the hole 10 is covered with the conductor film 74 and the conductor film 74 is electrically connected to the ground electrodes (760, 770), the generation of stray capacitance is prevented. be able to.

[0032]

As described above, according to the present invention, the following effects can be obtained. (A) Since the upper and lower yokes are separate and the ground terminal is provided separately from the yoke, the necessary grounding characteristics can be obtained without being substantially affected by the magnetic and electrical characteristics of the yoke. It is possible to provide a non-reciprocal circuit device that can be secured and can surely keep the yoke at the ground potential. (B) By maintaining the yoke at the ground potential, it is possible to provide a non-reciprocal circuit device capable of reducing the intermodulation distortion generated in a product incorporating this circuit device.

[Brief description of drawings]

FIG. 1 is an exploded perspective view of a non-reciprocal circuit device according to the present invention.

FIG. 2 is a plan view of a non-reciprocal circuit device according to the present invention.

FIG. 3 is a front sectional view taken along the line A3-A3 in FIG.

FIG. 4 is a front sectional view taken along the line A4-A4 in FIG.

FIG. 5 is a plan view of a supporting substrate forming the nonreciprocal circuit device according to the present invention, as viewed from the front surface side.

FIG. 6 is a plan view of the support substrate shown in FIG. 5 viewed from the back surface side.

FIG. 7 is an enlarged perspective view of the case shown in FIG.

FIG. 8 is a plan view of the case shown in FIG.

FIG. 9 is a plan view of the capacitor described in FIG.

10 is a cross-sectional view taken along line A10-A10 of FIG.

11 is a cross-sectional view taken along line A11-A11 of FIG.

FIG. 12 is a bottom view of the capacitor described in FIG.

FIG. 13 is a development view used to show an electrically equivalent circuit of the capacitor for nonreciprocal circuit device according to the present invention shown in FIGS. 9 to 12;

FIG. 14 is an equivalent circuit diagram of an isolator realized by using the nonreciprocal circuit device capacitor according to the present invention shown in FIGS. 9 to 12;

[Explanation of symbols]

 1 Support Substrate 2 Magnetic Material 3 Earth Conductor 4 Permanent Magnet 5, 6 Yoke 7 Capacitor 8 Case 9 Resistor Plate 10 Hole 11, 12, 13 Strip Conductor 14 Substrate 41 Conductor Film 74 Conductor Film 81, 82 Ground Terminal 83, 84 Input / Output Terminals 145, 146 Ground electrode 711 First dielectric layer 712 Second dielectric layer 713 Third dielectric layer 760, 770 Ground electrode 811, 812 Ground electrode

Claims (10)

[Claims] 1. A nonreciprocal circuit device in which the upper and lower yokes are provided as separate bodies, and a ground terminal is provided separately from the yoke. 2. The nonreciprocal circuit device according to claim 1, further comprising a conducting means for connecting the upper and lower yokes to the ground terminal. 3. The nonreciprocal circuit device according to claim 2, wherein a part of the conducting means is a conductor film provided on the surface of the permanent magnet. 4. The nonreciprocal circuit device according to claim 2, wherein a part of the conducting means is the permanent magnet itself. 5. The nonreciprocal circuit device according to claim 1, wherein a bottom surface side of the lower yoke is coated with an insulating resin. 6. A support substrate, a magnetic body, and a ground conductor, wherein the support substrate includes a plurality of strip conductors, and a ground electrode which is electrically connected to a ground terminal. The ground conductor is arranged so as to cover the magnetic body,
The permanent magnet is conductively connected to the ground electrode of the support substrate, the permanent magnet is disposed outside the ground conductor, is conductively connected to the ground conductor, and applies a DC magnetic field to the magnetic body. The nonreciprocal circuit device according to claim 1, 2, 3, 4, or 5, which covers the support substrate, the magnetic body, the ground conductor, and the permanent magnet so as to be conductively connected to the permanent magnet. 7. The nonreciprocal circuit device according to claim 6, wherein the ground conductor includes a shield conductor formed of a plate that covers a side surface portion and an upper surface portion of the magnetic body. 8. The nonreciprocal circuit device according to claim 1, wherein the conductor film covering the surface of the permanent magnet is formed by plating. 9. A capacitor is provided, wherein the capacitor includes a plurality of dielectric layers, each of the dielectric layers has electrodes on both main surfaces facing each other, and is laminated on each other to form a laminated body. The laminated body has ground electrodes on the front surface side and the back surface side, and has holes in the surface, and the magnetic body is inserted into the holes.
Alternatively, the nonreciprocal circuit device according to item 8. 10. The nonreciprocal circuit device according to claim 9, wherein the hole has an inner peripheral surface entirely covered with a conductor film, and the conductor film is electrically connected to the both ground electrodes.