JP2002208804A - Non-reciprocal circuit element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a non-reciprocal circuit element which stabilizes the electrical characteristics of an isolator and a circulator, and is also small and inexpensive. SOLUTION: In this non-reciprocal circuit element provided with an assembly 20, provided with a central conductor and a ferromagnetic substance and an electrode material 14a, in a magnetic circuit constructed by arranging a permanent magnet between an upper yoke 1 and a lower yoke 12, the lower yoke 12 and the electrode material 14a are a laminate united by cladding at least two or more kinds of metallic materials.

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 an irreversible transmission characteristic with respect to a high frequency signal, and more particularly, to a nonreciprocal circuit device used in a mobile communication system such as a cellular phone, and generally used for an isolator or a circulator. This is related to a non-reciprocal circuit element referred to as "reciprocal circuit element".

[0002]

2. Description of the Related Art Hitherto, non-reciprocal circuit devices such as isolators and circulators have been known as one of transmission / reception circuit components used in microwave bands and UHF bands for mobile phones, automobile phones, and the like. In general, isolators and circulators are used for the purpose of preventing breakage of an amplifier, and have a function of reducing insertion loss in a signal transmission direction and increasing reverse loss in a reverse direction. Hereinafter, in the specification of the present application, an isolator among non-reciprocal circuit devices will be described as an example.

In the case of this type of isolator, permanent magnets, three
It has a structure in which a magnetic assembly including a book center electrode and a garnet, a matching capacitor, a terminating resistor, and a resin case are provided. An external connection terminal to which an input / output port (matching capacitor) of the center electrode is connected is molded in the resin case. In such an isolator, when the above components are connected to each other, for example, cream solder (solder paste) is applied to the input / output port portion of each center electrode, and this is placed in a resin case.
The electrodes for the matching capacitor and the terminating resistor are placed in contact with each other, and with these components held by a jig, the cream solder is welded and solidified. Thereafter, the jig is removed and incorporated into the yoke. I have to.

FIG. 8 is an exploded perspective view showing an example of a conventional isolator. This isolator includes an upper yoke 1, magnets 2, an assembly 20, plate capacitors 8, 9, 10, a dummy resistor 11, a resin case 7, and a lower yoke 12. The assembly 20 prepares a conductive plate having a structure in which three center conductors 4, 5, and 6 project radially from a disk-shaped shield plate, and arranges the garnet disk 3 on the disk-shaped portion of the conductive plate. . Then, the three center conductors 4, 5, and 6 are folded and overlapped. At this time, the center conductors 4, 5, and 6 are insulated and stacked.

The resin case 7 has a circular concave portion 13a for an assembly at the center, and concave portions 13b, 13c and 13d for a capacitance element around the circular concave portion 13a. A connection electrode 14a is formed on the bottom of the concave portions 13b, 13c, 13d for the capacitive element and the concave portion 13a for the assembly. The connection electrode 14a serves as a ground conductor and an input / output terminal. The connection electrode 14a is integrally formed of a conductor plate having a thickness of about 0.1 mm, is exposed on the bottom side, and forms the external terminals 15a, 15b, 15d, and 15e on the side surfaces. These external terminals 15d and 15e are external terminals 1
5a and 15b are formed symmetrically on opposing surfaces and are not shown. Further, the terminal electrode portions 16b, 1 to which the center conductor is connected are connected.
6c is formed. These terminal electrode portions 16b, 16c
Are electrically connected to the external terminals 15c and 15f on the side surfaces, respectively. The external terminal 15f is formed symmetrically on the surface facing the external terminal 15c. Not shown.

The concave portion 13 for the capacitive element of the resin case 7
Capacitors 8, 9, and 10 are inserted into b, 13c, and 13d, respectively. This capacitive element is a flat plate capacitor having electrodes formed on the upper and lower surfaces thereof, and the electrode on the lower surface and the connection electrode 14a formed on the bottom of the recess are connected by soldering. The resistance element 11 is arranged, and one electrode of the resistance element 11 is connected to the connection electrode 14a by soldering.

Next, the above-mentioned assembly 20 is disposed in the circular recess 13a for the assembly of the resin case 7. At this time, the disk-shaped shield plate of the central conductor is soldered to the connection electrode 14a. Thereby, one end of the center conductor is grounded. One end of the center conductor 4 is connected to a capacitive element 8
And one terminal electrode of the resistance element 11. One end of the center conductor 5 is connected to the electrode on the upper surface of the capacitive element 9 and the terminal electrode portion 16b. One end of the center conductor 6 is connected to the electrode on the upper surface of the capacitive element 10 and the terminal electrode portion 1.
6c.

Then, the resin case 7 is arranged on the lower yoke 12. The lower yoke 12 has a structure that matches the concave portion 18 at the bottom of the resin case 7. Then, the lower yoke 12 and the back surface of the connection electrode 14a are connected by soldering. Further, surface mounting is enabled by the external terminals of the resin case 7. Then, the permanent magnet 2 for applying a DC magnetic field to the magnetic body 3 is positioned on the upper yoke 1, and the upper yoke 1 and the lower yoke 12 are fitted to each other to form an isolator.
It should be noted that if the above-mentioned resistance element is eliminated and an external terminal is attached in the same manner as other center conductors, a circulator can be obtained. Resistance element 11
Converts all output to the port into heat. The connection between the capacitor, the terminal electrode portion and the center conductor end portion is performed by, for example, soldering.

[0009]

In recent years, in the field of mobile communication, not limited to isolators, demands for smaller size, higher performance and lower cost have been increasing. Higher performance in dB units and further cost reduction have been issues. In a conventional non-reciprocal circuit device as exemplified in FIG. 8, a resin case having a conductor plate having a thickness of about 0.1 mm as a connecting part of a capacitor or an assembly and having an external terminal using the conductor plate is provided. In many cases, it is necessary to connect this to the lower yoke 12 by means such as soldering. Also, the lower yoke 12
And the back surface of the connection electrode 14a must be connected by soldering.
This required accurate soldering, and a skilled engineer was required to respond to this. However, it was still difficult to completely prevent short circuits and poor connections. Examples of a method for melting the cream solder include vapor phase soldering, reflow soldering in a high-temperature atmosphere, and soldering with a soft beam. However, in the case of the vapor phase soldering method, there is a problem that the use of an expensive Galden solution increases running costs. Further, in the case of reflow soldering in a high-temperature atmosphere, when the size of the isolator is changed, it is necessary to reset the temperature curve, and there is a problem that the setting change is troublesome. further,
In the case of the soldering method using a soft beam, heating can be performed at the same time if about 1 to 2 pieces are used, but a large number of pieces such as 50 to 100 pieces cannot be heated, and the soldering time is long, resulting in poor production efficiency. was there. Further, the connection electrode 14a made of a copper plate or the like has a thickness of 0.1 to 0.2 m.
m, there is a limit to the use of mobile phones where the need for extremely low height increases, including the thickness of the solder layer. For this reason, it is difficult to make the non-reciprocal circuit device extremely low-profile and miniaturized.
There is a problem that the component cost and the manufacturing cost increase. It is also disadvantageous for stabilization of electrical characteristics.

Accordingly, an object of the present invention is to provide a small and inexpensive non-reciprocal circuit device while stabilizing the electrical characteristics of an isolator and a circulator.

[0011]

The gist of the present invention is as follows. (1) A non-reciprocal circuit device including an assembly including a center conductor and a ferrimagnetic material in a magnetic circuit configured by disposing a permanent magnet between an upper yoke and a lower yoke, and electrodes. The non-reciprocal circuit device is characterized in that the lower yoke and the electrode are a laminate in which at least two kinds of metal materials are clad and integrated. (2) A non-reciprocal circuit element composed of an assembly having a center conductor and a ferrimagnetic material in a magnetic circuit configured by disposing a permanent magnet between an upper yoke and a lower yoke, and a resin case having electrodes. The lower yoke and the electrode are at least 2
The non-reciprocal circuit device is characterized in that the lower yoke and the resin case have an integrated structure formed by injection molding. (3) the metal materials have different electrical conductivities,
The non-reciprocal circuit device according to (1) or (2), wherein the assembly is mounted on one surface of a metal material having the highest electric conductivity. (4) The non-reciprocal circuit device according to (3), wherein at least one of the metal materials is a material having high electric conductivity selected from pure copper, oxygen-free copper, brass, and phosphor bronze. . (5) At least one of the metal materials is SPC
(3) or (4), which is a material having a high saturation magnetic flux density selected from C, 42 alloy and Fe-Co alloy.
It is a nonreciprocal circuit device of the description. (6) A metal film is formed on a surface of at least one of the metal materials with a metal or alloy containing at least one selected from silver, copper, gold, aluminum, and tin. The non-reciprocal circuit device according to any one of (1) to (5). (7) The non-reciprocal circuit device according to any one of (1) to (6), wherein the resin material forming the resin case is an engineering plastic. (8) The non-reciprocal circuit device according to (1) or (2), wherein the electrode material is at least one of a ground electrode, a ground conductor, a ground terminal, and an input / output terminal.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The main structure of the present invention is an integrated structure of a resin case having a copper plate and a clad of a lower yoke. The conventional resin case and the lower yoke are provided as separate members, and the resin case is provided with a ground (ground) and a copper plate constituting a connection terminal to the outside. However, in order to reduce the size of the nonreciprocal circuit device, the thickness of the copper plate is 0.2 to 0.4 m.
This is because it is no longer negligible. Therefore,
The gist of the present invention is that a non-reciprocal circuit device is constituted by a structure in which a resin case and a lower yoke are integrated by using a clad material in which copper and iron are integrated. Note that the present invention is applicable even when a resin case is not used. That is, the gist of the present invention is an integrated structure of a clad of a lower yoke and at least one electrode material such as a ground electrode, a ground conductor, a ground terminal, and an input / output terminal.

In the present invention, the lower yoke and the connection electrodes (the ground plane and the input / output terminals) are a laminate in which at least two or more metal materials are clad and integrated. Since the lower yoke functions as a yoke of the magnetic circuit, it is preferable that the lower yoke has a high saturation magnetic flux density. For example, pure iron, an iron alloy such as an Fe-Co alloy, SPCC, a 42 alloy (Fe-42% Ni) and the like can be mentioned. Since the connection electrode functions as a conductor, an electrode having high electric conductivity is preferable. For example, pure copper,
Oxygen-free copper, brass, phosphor bronze are mentioned. Therefore, a preferable combination is one in which a lower yoke of iron and a connection electrode of copper are clad. The use of such a clad composite material reduces reliance on skilled technicians, improves productivity, increases reliability, etc., which were not obtained by conventional soldering. It has been found that a remarkable effect of reducing insertion loss in the signal transmission direction can be obtained even in a technical field specific to the element. As a method of cladding the lower yoke and the connection electrode, rolling, hydrostatic molding such as HIP, CIP, welding, solid phase joining, and the like can be used. More preferably, both surfaces are cleaned before cladding. This is for good bonding. After the cladding, heat treatment can be performed to obtain an appropriate hardness.

Embodiment 1 A non-reciprocal circuit device according to an embodiment of the present invention will be described below with reference to FIG. FIG. 1 is an exploded perspective view showing the entire configuration of an isolator according to the present invention, FIG. 2 is a perspective view of a lower yoke integrally formed with a resin case, and FIGS.
6A and 6B are cross-sectional views, and FIG. 6 is a perspective view of a hoop-shaped lower yoke. As shown in FIG. 1, in the isolator according to the present invention, the lower yoke 12 and the connection electrode 14a are integrally processed by cladding. In addition, an assembly 20 in which a resin case 7 having external terminals and the lower yoke 12 are integrated, and three central conductors are superimposed on a magnetic material and mutually insulated in a concave portion of the resin case, capacitors 8, 9 , 10, and the resistive element 11 are mounted by applying cream solder to predetermined portions, and the upper and lower yokes on which permanent magnets are arranged are fitted. By forming them integrally, the configuration of the entire device becomes easy and productivity is greatly improved. At least one of a plurality of metal materials constituting the lower yoke 12 having an integral structure with the resin case is pure copper, oxygen-free copper, brass, phosphor bronze having high electric conductivity, and at least one is SPCC, 42 alloy. , Fe-Co alloys, and these metal materials are each cold-rolled or hot-rolled to about 30 to 300 μm. SPC is also on the upper yoke
It is preferable to use an alloy selected from C, 42 alloy and Fe-Co alloy. It is preferable to use the 42 alloy for the upper and lower yokes because of its excellent oxidation resistance. Also, since the upper and lower yokes are used as a part of a magnetic circuit, it is desirable to use SPCC or Fe-Co alloy having excellent magnetic properties. The composition of the Fe—Co alloy is, specifically, Co: 49, V: 2, C: ≦ 0.01 in mass%, respectively.
5, alloy containing Si: ≤ 0.10, Mn: ≤ 0.15, balance Fe and unavoidable impurities. This alloy plate can be manufactured as an ultra-thin plate having a thickness of about 100 μm, and generally has a maximum magnetic permeability of 15,000 and a saturation magnetic flux density of 2.25 Tesla. Where Co
Is selected in the range of 40 to 60% from the correlation between the frequency band and the magnetic characteristics, but is preferably around 50%. V is added to improve the cold workability, but is not more than 5% because it affects the magnetic characteristics. And 2% is desirable for ensuring workability. If this Fe—Co alloy is used for the yoke, magnetic flux leakage in the magnetic circuit is sufficiently and sufficiently suppressed even if the thickness of the yoke is reduced, so that the isolator can be further reduced in thickness and size.

If there were no upper and lower cases, the lines of magnetic force from one side of the magnet would return to the other side of the magnet through infinity. However, if the upper case and the lower case are formed from a magnetic material such as iron, and the magnet is covered with the upper case and the lower case, the lines of magnetic force from one side of the magnet do not pass through infinity, and the upper case and the lower case do not pass through. It will pass through the case and return to the other side of the magnet. In other words, the upper case and the lower case serve as a part of the magnetic circuit, in that the upper case and the lower case do not allow the lines of magnetic force from one side of the magnet to pass through infinity and pass through the upper case and the lower case. Through to return to the other side of the magnet. Further, a metal film may be formed on the surface of the metal material with a metal or alloy containing at least one of silver, copper, gold, aluminum, and tin by means of electrolytic or electroless plating.
The material of the metal film is properly used depending on the purpose. For example, when importance is attached to electric characteristics such as insertion loss characteristics, the electric resistivity is 5.5 μΩcm or less, preferably 3.0 μΩ.
cm, more preferably 1.8 μΩcm or less. When importance is attached to the solder wettability of the external terminal, an external terminal having excellent solder wettability can be formed by forming a metal film of tin or solder. In addition, the thickness of these metal films is 0.5 to
The thickness is 25 μm, preferably 0.5 to 10 μm, and more preferably 1 to 8 μm. The assembly 20, the capacitor 8,
The resistance elements 9 and 10 are mounted on one surface of the metal material having high electric conductivity. For this reason, it is possible to maintain the same electrical characteristics as those of the conventional isolator in which the resin case is formed using the conductor plate. Moreover, the integration of the lower yoke and the resin case is necessary for conventional isolators.
Eliminates the need for cream solder coating and fitting between the lower yoke and the resin case, thus reducing component costs and manufacturing costs. Stable electrical characteristics because there is no variation in the amount of solder applied or in the fitting state Is possible.

A lower yoke integrated with a resin case is formed by injection molding the metal material using a high heat-resistant thermoplastic engineering plastic such as a liquid crystal polymer or polyphenylene sulfide. At this time, at least the two or more types of metal materials constituting the lower yoke are punched into a predetermined shape by a press working machine and then bent to form a sheet material integrated by rolling or welding in advance. It is preferable to arrange and supply the hoop shape shown in the injection mold. Alternatively, a sheet material made of at least one or more types of metal materials may be punched into a predetermined shape by a press machine, bent, and supplied in combination with a plurality of hoop materials as shown in FIG. good. Further, after injection molding, the lead portion connecting the frame and the lower yoke is cut and bent by a mold, and the lead portion is connected to the external terminals 15c, 1c as shown in FIGS.
5f, 15a, and 15d were formed. When cutting the lead portion with a mold, the surface of the metal material is exposed, but when using SPCC as one of the plurality of metal materials,
In order to prevent the exposed portion from being oxidized, it is preferable that the plating treatment is further performed with a film thickness of about several μm. Further, on this conductive film, a conductive protective film layer such as nickel or chromium plating of about 0.2 to 2 μm may be formed from abrasion resistance, oxidation resistance and aesthetic factors.

When the bottom surface of the lower yoke is recessed from the external terminals as shown in FIG. 4, the reliability of the electrical connection between the external terminals and the mounting board can be improved.

Embodiment 2 Another embodiment of the non-reciprocal circuit device according to the present invention will be described with reference to FIG. I / O terminals 31, 32 or conductor 33
Are connected to the common ground electrode 2
1, a disk-shaped magnetic material (ferrite, garnet) 3 is arranged on the ground electrode 21. Each of the center conductors 4, 5, and 6 bent to the upper surface of the garnet disk 3 intersects at 120 degrees with an insulating sheet interposed therebetween. In FIG. 5, capacitors 8, 9, and 10 are arranged on a ground conductor 22, and the ends of each of the center conductors 4, 5, and 6 are connected to a counter electrode of each capacitor. The end of the center conductor 4 is connected to the input / output terminal 31, the end of the center conductor 5 is connected to the input / output terminal 32, and the end of the center conductor 6 is connected to the conductor 33. The other electrode is connected to the ground conductor 22. In addition, the ground electrode 21 in FIG. 5 is also electrically connected to the ground conductor 22 by soldering or the like. The grounding conductor 22 has a terminal 23
24, which are used as ground terminals for external connection. The magnet 2 for magnetizing the garnet disk 3 has a center conductor 4,
The garnet disk 3 is provided on each of the garnet disks 5 and 6. Further, the garnet disk 3, the central conductors 4, 5, 6,
The upper case 1 that houses the resistance element 11, the magnet 2, the ground conductor 22, and the like, and the lower case 12 are arranged as shown in FIG. The upper case 1 and the lower case 12 serve as a yoke of the magnetic circuit. Further, lower case 12 is electrically connected to ground conductor 22. The lower right part of FIG. 5 shows an example in which the lower case 12 and the ground conductor 22 are made of a clad composite material. The thickness is 0.3 mm. The clad is rolled,
By metallurgically joining the lower case 12 such as iron and the ground conductor 22 such as copper by hydrostatic molding or the like, it is possible to easily obtain an industrially more reliable material than solder or the like. The “cladding” in the present invention is not limited to the clad processing in the narrow sense described above, and those skilled in the art can use metallurgical bonding involving diffusion between both members such as welding and brazing.

[0019]

According to the present invention, in a non-reciprocal circuit device such as an isolator or a circulator, a non-reciprocal circuit device is formed by integrally forming a lower yoke and a ground conductor among upper and lower yokes forming a magnetic circuit. Can be downsized. Also,
This eliminates the need for cream solder application and mating processes between the lower yoke and the ground conductor, and does not cause variations in the amount of solder applied or in the mating state. It is possible to provide an inexpensive non-reciprocal circuit device capable of reducing insertion loss in the transmission direction and reducing component costs and manufacturing costs.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing an entire configuration of an embodiment of an isolator according to the present invention.

FIG. 2 is a perspective view of a lower yoke of a resin case and an integrated structure of the isolator according to the present invention.

FIG. 3 is a cross-sectional view of the lower yoke taken along line AA 'of FIG.

FIG. 4 is a cross-sectional view of the lower yoke taken along line BB ′ of an integral structure with a resin case used in the present invention.

FIG. 5 is an exploded perspective view showing the overall configuration of another embodiment of the isolator according to the present invention.

FIG. 6 is a perspective view of a hoop-shaped member made of a material that has been rolled or welded in advance, used in the present invention.

FIG. 7 is a perspective view showing a procedure for combining hoop-shaped members used in the present invention.

FIG. 8 is an exploded perspective view showing the entire configuration of a conventional isolator.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Upper yoke 2 Magnet 3 Magnetic body 4,5,6 Center conductor 7 Resin case 8,9,10 Capacitor 11 Resistance element 12 Lower yoke 21 Ground electrode 22 Ground conductor 23,24 Ground terminal 31,32 Input / output terminal 33 conductor

Claims (8)

[Claims] 1. A non-reciprocal circuit device including an assembly including a center conductor and a ferrimagnetic material in a magnetic circuit configured by disposing a permanent magnet between an upper yoke and a lower yoke, and an electrode material. A non-reciprocal circuit device, wherein the lower yoke and the electrode material are a laminate in which at least two types of metal materials are clad and integrated. 2. An irreversible assembly comprising an assembly having a center conductor and a ferrimagnetic material in a magnetic circuit configured by disposing a permanent magnet between an upper yoke and a lower yoke, and a resin case having an electrode material. A circuit element, wherein the lower yoke and the electrode material have an integrated structure in which at least two types of metal materials are clad and laminated, and the lower yoke and the resin case have an integrated structure by injection molding. Irreversible circuit element. 3. The non-reciprocal circuit according to claim 1, wherein the metal materials have different electric conductivity from each other, and the assembly is mounted on one surface of the metal material having the highest electric conductivity. element. 4. The non-reciprocal circuit according to claim 3, wherein at least one of the metal materials is a material having a high electric conductivity selected from pure copper, oxygen-free copper, brass, and phosphor bronze. element. 5. The irreversible material according to claim 3, wherein at least one of the metal materials is a material having a high saturation magnetic flux density selected from SPCC, 42 alloy, and Fe—Co alloy. Circuit element. 6. A metal film is formed on a surface of at least one of the metal materials with a metal or alloy containing at least one selected from silver, copper, gold, aluminum, and tin. The non-reciprocal circuit device according to claim 1, wherein: 7. The non-reciprocal circuit device according to claim 1, wherein the resin material forming the resin case is an engineering plastic. 8. The non-reciprocal circuit device according to claim 1, wherein the electrode material is at least one of a ground electrode, a ground conductor, a ground terminal, and an input / output terminal.