JP2002299911A - Non-reciprocal circuit element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make a non-reciprocal circuit element thin and inexpensive and also to obtain an expected resonance frequency in the non-reciprocal circuit element configured by arranging a permanent magnet 3, a magnetic assembly 45 formed by arranging three center electrodes while crossed to one another on the surface of a magnetic body 4, and three capacitors 6 for matching within a shielded space formed between an upper shield plate 2 and a lower shield plate 8. SOLUTION: In this non-reciprocal circuit element 1, a plurality of spacer parts 41 are formed on the surface of the magnetic body 4, and a gap part A is formed between the permanent magnet 3 and the magnetic body 4 by the spacer parts 41. Also, the input-output ports of the center electrodes and the poles of the capacitors for matching are held between capacitor supporting parts 81 formed in the lower shield plate and the permanent magnet 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a non-reciprocal circuit device such as an isolator and a circulator.

[0002]

2. Description of the Related Art In a portable telephone, as shown in FIG. 9, an isolator is provided between an amplifier (power amplifier PA) of a transmitting circuit and a transmitting / receiving antenna to absorb a reflected signal returning from the antenna to the amplifier. To protect the amplifier,
Further, stabilizing the load impedance of the amplifier and stabilizing the operation of the amplifier regardless of the fluctuation of the impedance of the antenna is performed. The isolator has such characteristics that the amount of attenuation is extremely small in the signal transmission direction and the amount of attenuation is extremely large in the reverse direction.

FIGS. 7 and 8 show a conventional isolator (10).
(JP-A-9-326604). The isolator (10) forms a magnetic closed circuit by combining a box-shaped upper shield plate (20) made of a magnetic metal and a substantially U-shaped lower shield plate (80) made of a magnetic metal. In the magnetic closed circuit, a disk-shaped permanent magnet (30), a resin substrate (70)
And a magnetic assembly (46).

The magnetic assembly (46) includes a disk-shaped magnetic body (40) made of ferrite, and three center electrodes (50a) (50b) (50c) arranged on the upper surface of the magnetic body (40). ), These center electrodes (50a) (50b) (50c) are arranged to intersect at an angle of 120 degrees, and are overlapped with each other via an insulating sheet (not shown), each center electrode (50a) (50b) (50c) The input / output port portions (52a) (52b) (52c) provided at one end of the (50c) project outside the magnetic body (40), and the center electrodes (50a) (50b )
An earth portion (not shown) provided at the other end of (50c) is connected to the bottom surface of the magnetic body (40), and a DC magnetic field from the permanent magnet (30) is applied to the magnetic assembly (46). Applied.

The resin substrate (70) has a rectangular bottom wall with four side walls erected, and a through hole (72) is opened at the center of the bottom wall. , A capacitor housing recess (not shown) and a resistor housing recess (not shown) are respectively formed. Further, two input / output port electrodes (77) and (77) are provided on the inner surface of the bottom wall, and each input / output port electrode (77) is provided with a terminal electrode (78) provided on the outer surface of the side wall. )
It is connected to.

The magnetic assembly (46) is accommodated in a through hole (72) of the resin substrate (70), and a ground portion (not shown) of the magnetic assembly (46) is connected to the lower shield plate (80). It is connected to the bottom. Three matching capacitors (60), (60), (60) and one terminating resistor (66) are arranged in the capacitor recess and the resistor recess of the resin board (70), respectively. The electrode provided on the lower surface and one electrode of the terminating resistor (66) are respectively connected to ground (not shown). or,
The electrodes provided on the upper surface of each capacitor (60) have input / output port portions (52a) (52b) (52c) of each center electrode (50a) (50b) (50c).
Is connected. In addition, two input / output ports
The tips of (52a) and (52b) are connected to the input / output port electrodes (77) and (77), respectively, and the tip of the remaining one input / output port (52c) is connected to the other electrode of the terminating resistor (66). It is connected.

[0007] A pressing member (9) is provided between the magnetic assembly (46) and the permanent magnet (30). The pressing member (9) is formed of a liquid crystal polymer and has elasticity, and is constituted by projecting three arms (91), (91), and (91) on the main body (90). A holding portion (92) having an arc-shaped cross section is protruded from the lower surface of the distal end of each arm (91). Also, the main body (90) and each arm
In (91), a through window is provided to reduce the weight of the pressing member (9). Here, the thickness L of the main body (90) is large enough to obtain sufficient elasticity, for example, 0.2 mm to
It is formed to 0.3 mm.

In the pressing member (9), the main body (90) has a permanent magnet (3).
A magnetic gap is formed between the permanent magnet (30) and the magnetic assembly (46) interposed between the magnetic assembly (0) and the magnetic assembly (46). or,
The arm portions (91), (91), (91) of the pressing member (9) are connected to the input / output port portions (52a) (52b) of the center electrodes (50a) (50b) (50c) of the magnetic assembly (46).
Replace (52c) with matching capacitors (60), (60), (60) and terminator
Each electrode of (66) and the input / output port electrode (77) are pressed against each other.

[0009]

By the way, in mobile phones, further miniaturization and cost reduction are required, and accordingly, miniaturization (thinning) and cost reduction of isolators are important. It has become a challenge. Further, in the isolator, the magnitude of the magnetic gap between the permanent magnet and the magnetic assembly (hereinafter referred to as gap length) and the resonance frequency have an inversely proportional relationship as shown in FIG. In order to obtain the resonance frequency, it is necessary to set the gap length with high accuracy.

However, in the conventional isolator (10), the thickness (L) of the main body (90) of the pressing member (9) needs to be a certain size, and thus there is a limit to the reduction in thickness. or,
The liquid crystal polymer forming the pressing member (9) is expensive and hinders cost reduction. Of course, the pressing member
Since (9) has elasticity, the thickness L of the main body (90) fluctuates due to an assembling error of the isolator (10) and the gap length fluctuates accordingly. There is a problem that the resonance frequency cannot be obtained.

An object of the present invention is to provide a non-reciprocal circuit device which can be reduced in thickness and cost and can obtain a desired resonance frequency.

[0012]

According to the nonreciprocal circuit device of the present invention, a permanent magnet is provided inside a magnetically shielded space.
A magnetic circuit is formed by disposing (3), and in the magnetic circuit,
A magnetic assembly in which a plurality of center electrodes (5a) (5b) (5c) are arranged on the surface of a magnetic body (4) so as to cross each other in an electrically insulated state.
(45) and input / output port (51a) of each center electrode (5a) (5b) (5c)
(51b) Matching capacitors to which (51c) is connected (6) (6) (6)
And the capacitors (6), (6), (6) and the magnetic assembly (45).
And a resin substrate (7) in which the resin substrate (7) is stored.
Are provided with a plurality of external connection terminal electrodes (76) (76), and the input / output ports (51a) (51b) are connected to the terminal electrodes (76) (76). On the surface of the magnetic body (4) facing the permanent magnet (3), three or more spacer portions (41) protruding toward the permanent magnet (3) are provided. A magnet (3) is supported, and a plurality of the center electrodes (5a) (5a) are formed in a gap portion A formed between the facing surfaces of the permanent magnet (3) and the magnetic body (4) by the spacer portion (41). 5b) and (5c) are installed, and the input / output port (51) of each center electrode (5a) (5b) (5c)
a) (51b) (51c) project outward from the gap portion A,
It is pressed directly by the permanent magnet (3) and pressed against the electrodes of the matching capacitors (6), (6), (6). The spacer (41) is formed integrally with the magnetic body (4).

In the nonreciprocal circuit device according to the present invention, the spacer (41) interposed between the magnetic body (3) and the permanent magnet (4).
Determines the size (gap length) of the gap A formed between the magnetic body (3) and the permanent magnet (4). Therefore, by forming the spacer portion (41) at a height corresponding to a predetermined gap length, a desired resonance frequency according to the gap length can be obtained. Also, each center electrode
The input / output ports (51a), (51b) and (51c) of (5a), (5b) and (5c) are directly pressed by the permanent magnet (3) to
(6) Since the electrodes are pressed against the electrodes (6) and (6), it is not necessary to provide a conventional pressing member.

In another specific configuration, the upper shield plate
(2) and the lower shield plate (8) are combined to form the magnetically shielded space, and the lower shield plate (8) is provided with the matching capacitors (6), (6) and (6). Capacitor support portions (81), (81), (81) for supporting at the height positions of the permanent magnet (3) and the capacitor support portions (81), (81), (81) of the lower shield plate (8) are provided. Between the input and output ports (51a) (51b) (51c) of the center electrodes (5a) (5b) (5c) and the matching capacitor (6)
(6) The electrode of (6) is sandwiched.

According to the specific configuration, the permanent magnet (3)
The input / output ports (51a) (51b) of the center electrodes (5a) (5b) (5c) by the capacitor support portions (81) (81) (81) of the lower shield plate (8)
The electrode (51c) and the electrodes of the matching capacitors (6), (6) and (6) are sandwiched between each other, and the electrical and mechanical connection between them is maintained.

[0016]

According to the non-reciprocal circuit device of the present invention,
Since there is no need to equip the pressing member used in the conventional non-reciprocal circuit device, it is possible to reduce the thickness and cost, and of course, by setting the gap length accurately with the spacer, the desired resonance is achieved. You can get the frequency.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to an isolator will be specifically described below with reference to the drawings. As shown in FIGS. 1 and 2, the isolator according to the present invention includes a U-shaped upper shield plate (2) made of a magnetic metal and a substantially U-shaped lower shield plate (8) made of a magnetic metal. To form a magnetic closed circuit, in which a rectangular plate-shaped permanent magnet (3), a resin substrate (7), and a magnetic assembly (45) are provided.
And are arranged.

As shown in FIGS. 3 to 5, the magnetic assembly (45) includes a rectangular plate-shaped magnetic body (4) made of ferrite, and three magnetic bodies (4) arranged so as to cover the upper surface of the magnetic body (4). Center electrode (5a)
(5b) and (5c). On the upper surface of the magnetic body (4), four spacer portions (41), (41), (41) and (41) having the same height are formed integrally with the magnetic body (4) at the four corners. . The three center electrodes (5a) (5b) (5c) are insulating sheets
(Not shown), they were arranged on the top surface of the magnetic body (4) at an angle of 120 degrees, and were provided at one end of each of the center electrodes (5a) (5b) (5c). The input / output port portions (51a) (51b) (51c) project outward and a ground portion (not shown) provided at the other end of each of the center electrodes (5a) (5b) (5c)
Is connected to the bottom surface of the magnetic body (4).

As shown in FIG. 2, the resin substrate 7 has a rectangular bottom wall with four side walls standing upright, and a through hole 71 is formed in the center of the bottom wall. The magnetic assembly (45) is accommodated in the through hole (71), and the magnetic assembly (45)
(Not shown) is connected to the bottom surface of the lower shield plate (8). As shown in FIG. 3, two input / output port electrodes (75) and (75) are provided on the inner surface of the side wall, and each input / output port electrode (75) is provided on the outer surface of the side wall. The external connection terminal electrodes (76) and (76).

As shown in FIGS. 1 and 2, three capacitor supporting portions protruding upward are provided on the bottom surface of the lower shield plate (8).
(81), (81) and (81) are formed. An electrode provided on the lower surface of each capacitor (6) and one electrode of the terminating resistor (65) are respectively connected to each capacitor support (81). or,
As shown in FIG. 3, electrodes provided on the upper surface of each capacitor (6) have an input / output port (5) of each center electrode (5a) (5b) (5c).
1a, 51b, and 51c are connected. Further, the tips of the two input / output port portions (51a) and (51b) are connected to the two input / output port electrodes (75) and (75), respectively, and the remaining one of the input / output port portions (51c) is connected. The tip is connected to the other electrode of the terminating resistor (65).

As shown in FIG. 1, a permanent magnet (3) is provided on the inner surface of the upper shield plate (1), while a lower shield plate (1) is provided.
A magnetic assembly (45) is installed on the inner surface of (8), and a resin substrate (7) is sandwiched between an upper shield plate (1) and a lower shield plate (8). The permanent magnet (3) is supported by the four spacer portions (41), (41), (41), and (41) formed on the magnetic body (4) of the magnetic assembly (45). body
A gap A is formed between (4) and the permanent magnet (3). The gap A is formed at a height t of the spacer (41).
And the gap portion A
Accommodates three center electrodes (5a) (5b) (5c). still,
In FIG. 1, the illustration of the center electrode accommodated in the gap portion A is omitted.

In the isolator (1), a DC magnetic field generated from the permanent magnet (3) is applied to the magnetic assembly (45), and a gap formed between the magnetic body (4) and the permanent magnet (3). A resonance frequency corresponding to the gap length of the portion A is obtained.

Next, a manufacturing process of the isolator will be described. In manufacturing the magnetic material (4) shown in FIGS. 4 and 5, YIG (yttrium-iron-garnet mixture) was used.
Using a dicing saw, a depth of 0.1 in the X and Y directions orthogonal to each other is
A groove of 3 mm is formed, so that the height t is 0.1.
Four 3 mm spacer portions (41), (41), (41) and (41) are formed.

Thereafter, three center electrodes (5a) are attached to the magnetic body (4).
(5b) Wind the (5c) to produce the magnetic assembly (45). At this time, an insulating sheet (not shown) made of polyimide is provided on the upper surface of each of the center electrodes (5a), (5b), and (5c). The thickness of the center electrode is 0.030 mm per sheet, and the thickness of the insulating sheet is 0.010 mm per sheet. Therefore, the thickness of the portion where the three center electrodes (5a), (5b), and (5c) overlap with the three insulating sheets is 0.12 mm, and the depth of the groove formed in the magnetic body (4) is equal to the depth. Since it is 0.13 mm, 3
The center electrodes (5a), (5b), and (5c) are accommodated.

The lower shield plate (8) is subjected to a press working so that three capacitor support portions (81), (81), (8) are formed as shown in FIG.
Form 1). When the isolator (1) of the present invention is assembled as shown in FIG. 1, each capacitor support (81) is provided with a center electrode between the capacitor support (81) (81) and the permanent magnet (3). (5a) The input / output port portions (51a) (51b) of (5b) and the matching capacitor (6) or the terminating resistor are formed at a predetermined height to be sandwiched therebetween.

In the assembling step, a resin substrate (7) is installed on the bottom surface of the lower shield plate (8), and at a predetermined position (see FIG. 3) of the capacitor supporting portions (81), (81), (81). The electrodes of each capacitor (6) and the terminating resistor (6
The electrode of 5) is arranged. Further, a solder paste is applied to the other electrode of each capacitor (6) and the other electrode of the terminating resistor (65). Then, as shown in FIG. 3, after the magnetic assembly (45) is fitted in the through hole of the resin substrate (7) in a predetermined direction, the input / output port portions (5a), (5b), and (5c) of the center electrodes (5a) 51a) (51b) (51c)
To the other electrode of each capacitor (6) and the other electrode of the terminating resistor (65).

Next, as shown in FIG. 1, an unmagnetized permanent magnet (3) is placed on the magnetic assembly (45),
Put on (2) and assemble the isolator (1). Then, the isolator (1) is housed in a solder reflow furnace,
By melting the solder paste interposed between the bonding surfaces, electrical and mechanical bonding between the bonding surfaces is performed. Finally, the unmagnetized permanent magnet (3) is magnetized by a magnetizer to complete the isolator (1) according to the present invention.

In the isolator (1) thus obtained, suction is applied between the permanent magnet (3) and the magnetic body (4) and between the permanent magnet (3) and the lower shield plate (8). Magnetic force acts on the permanent magnet (3) and the magnetic body (4) to attract each other with a sufficient force, and the permanent magnet (3) and the lower shield plate (8) attract each other with a sufficient force. Become
The assembled state of FIG. 1 is maintained.

In the isolator (1) of the present invention, as shown in FIG. 1, the permanent magnet (3) and the magnetic material (4) are formed by a spacer (41) projecting from the surface of the magnetic material (4). ), A gap portion A is formed, and the gap length of the gap portion A is accurately defined by the height t of the spacer portion (41), so that the spacer portion (41) is set to a predetermined height t. By finishing, a predetermined gap length can be set, and as a result, a desired resonance frequency can be obtained.

The center electrodes (5a), (5b) and (5c) are provided between each capacitor support (81) of the lower shield plate (8) and the permanent magnet (3).
The input / output port sections (51a), (51b), and (51c) of each of the input / output ports are held between the electrodes of the matching capacitors (6), (6), (6) or the terminating resistor (65). (51a) (51b) (51c) and the respective electrodes are securely bonded, so that the pressing member used in the conventional isolator is unnecessary, thereby reducing the thickness and cost of the isolator. Is possible.

The input / output port portions (51a) (51b) (51c) of the center electrodes (5a) (5b) (5c) are soldered to the electrodes of the capacitors (6) and the terminals of the terminating resistor (65). In the case of joining by a reflow process, the solder is re-melted in a state where each input / output port part (51a) (51b) (51c) and each electrode are pressed against each other, so that
Reliable solder joining is realized.

Further, in the isolator (1) according to the present invention, the gap length t shown in FIG.
On the other hand, the gap length of the conventional isolator is from 0.2 mm to 0.3 mm, and the gap length is reduced. As a result, the resonance frequency of the isolator increases (see FIG. 6), and the attenuation of the isolator in the signal transmission direction decreases.

The configuration of each part of the present invention is not limited to the above embodiment, and various modifications can be made within the technical scope described in the claims. For example, in the above embodiment, the magnetic material
The spacer portion (41) is formed integrally with (4), but the spacer portion is formed separately from the magnetic material (4) to form a permanent magnet.
A configuration interposed between (3) and the magnetic body (4) can also be adopted.

[Brief description of the drawings]

FIG. 1 is a sectional view of an isolator according to the present invention.

FIG. 2 is an exploded perspective view of the isolator.

FIG. 3 is a plan view showing an internal configuration of the isolator.

FIG. 4 is a perspective view of a magnetic assembly provided in the isolator.

FIG. 5 is a side view of the magnetic assembly.

FIG. 6 is a graph illustrating a relationship between a resonance frequency of an isolator and a gap length.

FIG. 7 is a sectional view of a conventional isolator.

FIG. 8 is an exploded perspective view of a conventional isolator.

FIG. 9 is a block diagram showing a transmitting / receiving section of a mobile phone using an isolator.

[Explanation of symbols]

 (1) Isolator (2) Upper shield plate (3) Permanent magnet (4) Magnetic body (45) Magnetic assembly (5a) Center electrode (5b) Center electrode (5c) Center electrode (51a) Input / output port (51b) ) I / O port (51c) I / O port (6) Matching capacitor (7) Resin board (8) Lower shield plate (9) Pressing member

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Kozo Ishihara 1-1, Sanyocho, Daito-shi, Osaka Sanyo Electronics Parts Co., Ltd. F-term (reference) 5J013 EA01 FA07

Claims (3)

[Claims] A magnetic circuit is formed by arranging a permanent magnet (3) inside a space shielded by magnetic field, and a plurality of center electrodes (5a) (5a) (5 5b) and (5c) are arranged so as to cross each other in an electrically insulated state, and the input / output port (5) of each of the center electrodes (5a) (5b) (5c).
1a) Matching capacitors to which (51b) and (51c) are connected (6) (6)
(6), the capacitors (6), (6), (6) and the magnetic assembly
A resin substrate (7) in which (45) is stored is provided.
(7) is provided with a plurality of external connection terminal electrodes (76) and (76), and the terminal electrodes (76) and (76) are provided with a plurality of the input / output ports (51).
a) In the nonreciprocal circuit device to which (51b) is connected, three or more spacers protruding toward the permanent magnet (3) are provided on a surface of the magnetic body (4) facing the permanent magnet (3). (41), a permanent magnet (3) is supported by the spacer portion (41), and a permanent magnet is provided by the spacer portion (41).
Gap portion A formed between opposing surfaces of (3) and magnetic body (4)
The plurality of center electrodes (5a) (5b) (5c) are installed, and the input / output ports (51a) (51b) (51c) of each center electrode (5a) (5b) (5c)
Protrudes outward from the gap portion A to form a permanent magnet (3).
Directly pressed by the matching capacitor (6)
(6) A non-reciprocal circuit device characterized by being pressed against the electrode of (6). 2. The non-reciprocal circuit device according to claim 1, wherein the spacer portion (41) is formed integrally with the magnetic body (4). 3. A magnetically shielded space is formed by combining an upper shield plate (2) and a lower shield plate (8), and the lower shield plate (8) includes the matching capacitor.
(6) Capacitor support portions (81), (81), (81) for supporting the (6) and (6) at predetermined height positions are provided, and the capacitors of the permanent magnet (3) and the lower shield plate (8) are provided. Between the support portions (81), (81), and (81), the input / output ports (51a), (51b), (5) of the center electrodes (5a), (5b), (5c)
3. The non-reciprocal circuit device according to claim 1, wherein 1c) and electrodes of the matching capacitors (6), (6), (6) are sandwiched.