JPH0715212A - Irreversible circuit element - Google Patents

Abstract

PURPOSE:To provide a miniaturized irreversible circuit element equipped with a filter circuit. CONSTITUTION:An isolator circuit is composed of a permanent magnet 2, magnetic substance 3, mesh-shaped central conductor 5 and substrate 6. An LC filter circuit connected to the isolator circuit is composed of conductor patterns formed at the respective layers of a laminated substrate 7, and an isolator element integrating these circuits is formed. Thus, since the isolator element with the built-in LC filter circuit can be compactly formed, an equipment to use the isolator element can be miniaturized.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to nonreciprocal circuit devices such as circulators and isolators having a filter circuit.

[0002]

2. Description of the Related Art Conventionally, non-reciprocal circuit elements such as circulators and isolators have a characteristic of transmitting electric power only in a predetermined specific direction and not transmitting electric power in the reverse direction.
Utilizing this characteristic, for example, a circulator is used as a multi-frequency demultiplexer combined with a transmission / reception demultiplexer and a filter circuit, and an isolator is used for impedance matching in a high-frequency circuit, transistor protection of an amplifier, etc. .

Recently, with the downsizing of communication equipment, MI
The distributed constant type in which a hole is formed in a part of the C substrate and microwave ferrite is embedded, and the lumped constant type in which the circumferential part that does not contribute much to the nonreciprocity of microwave ferrite is replaced with an inductor and a capacitor are small isolator and It is used as a circulator.

Both the distributed constant type and the lumped constant type have a great feature in forming a circuit, an inductance, or a capacitance on a substrate.

Further, when the circulator element and the isolator element are used in a communication device such as a car telephone and a parent-child cordless telephone, a filter circuit is connected to both or one of the input / output terminals of these non-reciprocal circuit elements. Often used.

[0006]

The distributed constant type circulator or isolator formed on the MIC substrate described above can be integrated by combining a distributed constant type LC filter formed by a microstrip line at its input / output portion. Since the lumped-constant type circulator or isolator is itself housed in one package, when connecting a filter circuit such as a low-pass filter (LPF) to the input / output section, a filter circuit is formed outside this. Must be done, which is an obstacle to downsizing of communication equipment.

In view of the above problems, it is an object of the present invention to provide a small non-reciprocal circuit device having a filter circuit.

[0008]

In order to achieve the above-mentioned object, the present invention comprises three central conductors having one end connected to each other and intersecting at 120 degrees, and a magnetic body facing the central conductor.
In a nonreciprocal circuit device including a capacitor connected to the other end of each of the central conductors and a substrate in which a hole for inserting and arranging the magnetic body is formed, the substrate is formed of a laminated substrate, A filter circuit connected to the central conductor is provided on at least one side of the input / output side, and the capacitor, the capacitor and the inductor forming the filter circuit are formed by printed conductors provided on each layer of the laminated substrate. We propose a non-reciprocal circuit device.

[0009]

According to the present invention, the substrate in which the hole for inserting and arranging the magnetic body is formed is formed of the laminated substrate and is connected to the central conductor on at least one of the input and output sides of the central conductor. A filter circuit is provided. Further, a capacitor connected to the other end of each of the three center conductors, and a capacitor and an inductor forming the filter circuit are formed by printed conductors provided on each layer of the laminated substrate.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. 1 is a configuration diagram showing an isolator element according to a first embodiment of the present invention, and FIG. 2 is a circuit diagram thereof. In FIG. 1, 1a and 1b are metal cases, 2 is a permanent magnet, 3 is a magnetic body, 4a and 4b are insulating films, 5 is a mesh-shaped central conductor, and 6
Is a substrate for capacitor formation, and 7 is a laminated substrate for LC filter formation.

The permanent magnet 2 has a disk shape, and the magnetic body 3 has a disk shape having substantially the same area as the permanent magnet 2.

The reticulated center conductor 5 is a circular shield plate 51.
And three center conductors 52 to 54 radially extending from the shield plate 51, and the center conductors 52 to 54 are formed so as to intersect each other at an angle of 120 degrees.

Further, as shown in FIG. 3, the magnetic body 3 is arranged on the shield plate 51 of the mesh-shaped center conductor 5,
A central conductor portion is formed by bending 2 to 54 and wrapping the magnetic body 3. At this time, the insulating sheets 4a and 4b are arranged between the central conductors 52 to 54 for insulation. The central conductors 52 to 54 form the inductors La, Lb, and Lc shown in FIG.

The substrate 6 is made of an alumina substrate or a dielectric substrate having a predetermined thickness, and a circular opening 6a having a predetermined area is formed in the center thereof. Further, on the surface of the substrate 6, conductor patterns 61, 62, 63 forming electrodes of the capacitors Ca, Cb, Cc and a conductor pattern 64 for grounding are formed by printing, and between the conductor patterns 63 and 64. Resistor 6 connected to these
5 is formed by printing. The resistor 65 constitutes a terminating resistor R, and its resistance value is set to, for example, 50 ohms. Further, through holes 61a, 62a, 64a are formed at predetermined positions of the conductor patterns 61, 62, 64.

The laminated substrate 7 is made of a ceramic dielectric,
The first to seventh layers 71 to 77 are provided, and each layer 7 is
1 to 77 are printed with a conductor pattern forming a capacitor C1 and inductors L1 and L2 that form an LC filter. That is, as shown in FIG. 4, on the upper surface of the first layer 71, a conductor pattern 711 for grounding is formed on almost the entire surface except the regions corresponding to the through holes 61a and 62a, and the conductor patterns 711 corresponding to the through holes 61a and 62a are formed. Through holes 71a and 71b are formed at the positions. Also,
A predetermined portion of the peripheral edge of the conductor pattern 711 is conductively connected to the outer conductor 7a formed on the peripheral surface of the laminated substrate 7.

On the upper surface of the second layer 72, a conductor pattern 721 serving as an electrode of the capacitor C1 is formed on almost the entire surface except the regions corresponding to the through holes 71a and 71b, and the conductor patterns 721 are formed at the positions corresponding to the through holes 71a and 71b. Through holes 72a and 72b are formed.

The through hole 72 is formed in the third layer 73.
through holes 73a, 73 at positions corresponding to a, 72b.
b is formed.

On the upper surface of the fourth layer 74, inductors L1,
A substantially Y-shaped conductor pattern 741 forming L2 is formed, and its central end portion 741a is conductively connected to the outer conductor 7b formed on the peripheral surface of the laminated substrate 7. Further, through holes 741b and 741c are formed at both ends of the conductor pattern 741. Further, the through holes 73a, 7
Through holes 74a and 74b are formed at positions corresponding to 3b.

On the upper surface of the fifth layer, inductors L1 and L2 are provided.
Forming substantially L-shaped conductor patterns 751 and 752, and the respective ends 751a and 752a have through holes 741b and 741.
It is connected to c and through holes 751b and 752b are formed at the other end. Further, the through holes 74a, 74b
Through holes 75a and 75b are formed at positions corresponding to.

On the upper surface of the sixth layer, a conductor pattern 761 conductively connected to the external electrode 7c formed on the peripheral surface of the laminated substrate 7, a conductor pattern 762 forming the inductor L1,
And conductor pattern 763 forming a part of the capacitor Ca
Are formed. The conductor pattern 762 is conductively connected to the external electrode 7d formed on the peripheral surface of the laminated substrate 7,
The conductor pattern 761 is conductively connected to the through hole 75a, and the conductor pattern 763 is conductively connected to the through hole 75b.

On the lower surface of the seventh layer 77, the external electrodes 7c, 7
A conductor pattern 77 for grounding which is connected to the conductor pattern 711 for grounding by the outer conductor 7a in a predetermined region except the vicinity of d.
1 is formed.

In this assembly, the substrate 6 is superposed on the upper surface of the laminated substrate 7 to form one laminated substrate. At this time, the conductor pattern 64 is connected to the conductor pattern 711 for grounding through the through hole 64a. Further, the conductor pattern 61 serving as the electrode of the capacitor Cc is connected to the conductor pattern 761 and the external electrode 7c through the through holes 61a, 71a, 72a, 73a, 74a and 75a, and the conductor pattern 62 serving as the electrode of the capacitor Ca is through. Holes 62a, 71b, 72b, 73b, 74b, 75b
Is connected to the conductor pattern 763 via.

Further, the reticulated center conductor 5 enclosing the magnetic body 3
Is inserted and arranged in the opening 6a of the substrate 6, and the center conductor 52
The end portions of 54 to 54 are connected to the conductor patterns 61 to 63 serving as the capacitor electrodes on the substrate 6. At this time, the shield plate 51 of the reticulated center conductor 5 is conductively contacted with the grounding conductor pattern 711.

Further, the permanent magnets 2 are superposed on the central conductors 52 to 54, all of which are metal cases 1a and 1b.
Is stored in.

According to the above configuration, the LC filter circuit is integrated in the isolator element, so that the filter circuit conventionally formed outside the isolator element can be omitted, and communication using the isolator element can be omitted. It is possible to reduce the size of equipment and the like.

Next, a second embodiment of the present invention will be described.
FIG. 5 is a configuration diagram showing an isolator element of the second embodiment,
FIG. 6 is a configuration diagram showing a laminated substrate 7A in the second embodiment. In the figure, the same components as those in the first embodiment described above are designated by the same reference numerals and the description thereof will be omitted. Further, the difference between the first embodiment and the second embodiment is that a laminated board 7A is used instead of the laminated board 7 in the first embodiment, and an external conductor 7a that is not directly related to connection with an external circuit,
7b has been removed.

That is, the conductor pattern 721 formed on the second layer 72 of the laminated substrate 7A is formed through the through hole 72c formed on the second layer 72 and the through hole 73c formed on the third layer 73. It is connected to the central end portion 741a of the conductor pattern 741 of the four layers 74. Further, the grounding conductor pattern 711 of the first layer 71 includes the first layer 71 to the seventh layer 77.
Through holes 71c, 72d, 73d, 7 formed in
4c, 75c, 76c and 77a are connected to the grounding conductor pattern 771 formed on the lower surface of the seventh layer 77.

In this embodiment, the isolator element is used as the non-reciprocal circuit element, but it is not limited to this. For example, the circulator element can be easily configured by removing the resistor 65 in the present embodiment, and the same effect can be obtained.

The configuration of this embodiment is an example, and the present invention is not limited to this.

[0030]

As described above, according to the present invention, the filter circuit is provided on at least one of the input and output sides of the center conductor, and the capacitor and inductor forming the filter circuit and the three center conductors are provided. Since the capacitor connected to the other end of each is formed by the printed conductor provided on each layer of the laminated substrate, a non-reciprocal circuit device having a filter circuit can be formed in a small size. It is possible to reduce the size of equipment used.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an isolator element according to a first embodiment of the present invention.

FIG. 2 is a circuit diagram showing an isolator element of the first embodiment.

FIG. 3 is a diagram showing a surrounding structure of a central conductor and a magnetic body in the first embodiment.

FIG. 4 is a configuration diagram showing a laminated substrate in the first embodiment.

FIG. 5 is a configuration diagram showing an isolator element according to a second embodiment.

FIG. 6 is a configuration diagram showing a laminated substrate in a second embodiment.

[Explanation of symbols]

1a, 1b ... Metal case, 2 ... Permanent magnet, 3 ... Magnetic body,
4a, 4b ... Insulating film, 5 ... Reticulated center conductor, 51 ...
Shield plate, 52-54 ... Central conductor, 6 ... Substrate, 61-
63 ... Conductor pattern (capacitor electrode), 64 ... Grounding conductor pattern, 65 ... Resistor, 7, 7A ... Laminated substrate,
711,771 ... Conductor pattern for grounding, 721,763 ... Conductor pattern (electrode for capacitor), 741,751,752,762 ... Conductor pattern (for forming inductor), 7a, 7b ... External conductor, 7
c, 7d ... External electrodes.

Claims (1)

[Claims] 1. A central conductor having one end connected to each other and intersecting at 120 degrees, and a magnetic body facing the central conductor.
In a nonreciprocal circuit device comprising a capacitor connected to the other end of each of the central conductors and a substrate having a hole for inserting and arranging the magnetic body, the substrate is formed of a laminated substrate, A filter circuit connected to the central conductor is provided on at least one side of the input / output side, and the capacitor and the capacitor and the inductor forming the filter circuit are formed by printed conductors provided on each layer of the laminated substrate. A non-reciprocal circuit device characterized by the above.