JP2003060410A - Nonreciprocal circuit element and communication apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a compact, low-height and low-cost non-reciprocal circuit element and a communication apparatus. SOLUTION: An isolator 1 is composed of a ferrite 20, a center electrode, a resin-made terminal case 3, a matching capacitor element C1, etc., a filtering capacitor element C4, a filtering inductor element L, a rectangular permanent magnet 9, a metal-made lower case 8, etc. A connecting metal 17, etc., are insert-molded in the terminal case 3. One end of the metal 17 is exposed in the bottom 3a of the case 3, and its central part is exposed in the bottom of a window 3 for housing the capacitor element C4. A connection metal 17 formed in the case 3 has an L-shape, a band-pass filter, composed of the inductor element L and the capacitor element C4, is disposed at a position which is different from the matching capacitor element C1, etc., in a direction perpendicular to the thickness of the ferrite 20.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a non-reciprocal circuit device and a communication device.

[0002]

2. Description of the Related Art Conventionally, as a non-reciprocal circuit device mounted in a mobile communication device such as a mobile phone, there has been disclosed in Japanese Unexamined Patent Publication No.
The one described in Japanese Patent No. 56503 is known. As shown in FIG. 8, the isolator (non-reciprocal circuit device) 140 is
The center electrode 15 is attached to the ferrite 154 to which a DC magnetic field is applied.
1 to 153 are arranged so as to intersect with each other, and the matching capacitor elements C1 to C3 are connected to the port portions P1 to P3 of each center electrode and the ground terminal 173, respectively, to form a nonreciprocal circuit. Port portion P1 of the center electrode 151 and the input terminal 1
A solenoid-shaped inductor element L for a filter is connected to the terminal 71. By connecting the filter capacitor element C in series to the input terminal 171, the bandpass filter (BPF) is formed by the filter capacitor element C and the filter inductor element L.
Are configured. This bandpass filter has 2
This is to obtain a large amount of attenuation in the frequency band of unwanted radiation of the overtone and overtone. In addition, R is a resistance element, 168 is a metal lower case, 163 is a resin terminal case, 172
Indicates an output terminal.

There is also known an isolator 141 shown in FIG. 9 in which the direction in which the filter inductor element L is mounted (winding direction) is vertical.

[0004]

By the way, in recent years, with the demand for small size, low profile, and low cost of mobile phones, demands for small size, low profile, and low cost for non-reciprocal circuit devices have become stronger. Is coming. However, the conventional structure cannot sufficiently reduce the height.

[0005] Further, as the price of mobile phones has been reduced, set manufacturers are increasingly demanding cost reductions for non-reciprocal circuit elements. However, the inductor element L for filters and the capacitor element C for filters forming a bandpass filter are required.
Due to the complexity of the mounting process, it was impossible to meet the demand for cost reduction.

Therefore, an object of the present invention is to provide a non-reciprocal circuit device and a communication device which are small in size, low in height and low in cost.

[0007]

To achieve the above object, the nonreciprocal circuit device according to the present invention comprises (a) a permanent magnet and (b) a ferrite to which a direct current magnetic field is applied by the permanent magnet. A center electrode assembly composed of a plurality of center electrodes arranged on the ferrite; (c) a matching capacitor element electrically connected to at least one of the center electrodes; and (d) at least a filter. A filter comprising a capacitor element for filter and an inductor element for filter, and (e) a connecting fitting for electrically connecting any one of the capacitor element for filter and the inductor element for filter to one of the center electrodes. (F) At least the center electrode assembly, the matching capacitor element, and the filter inductor element are housed, and the connecting fitting is inserted. A molded resin terminal case, and (g) a metal case incorporated in the resin terminal case and at least accommodating the permanent magnet, the center electrode assembly, the matching capacitor element, and the filter inductor element. And (h) at least the matching capacitor element and the filter inductor element are arranged on a side of the ferrite, and the matching capacitor element and the filter are arranged in a direction perpendicular to a thickness direction of the ferrite. The inductor elements for use are arranged at different positions.

More specifically, the filter constitutes a bandpass filter composed of a filter capacitor element and a filter inductor element, and the filter capacitor element faces the first capacitor electrode and the first capacitor electrode. It has two capacitor electrodes, the filter inductor element is connected to the first capacitor electrode, the second capacitor electrode is connected to the connection fitting, the filter capacitor element is housed in the resin terminal case, and the filter is provided on the side of the ferrite. The capacitor element for filter is arranged, and the capacitor element for filter is arranged at a position different from the capacitor element for matching and the inductor element for filter in the direction perpendicular to the thickness direction of the ferrite.

Alternatively, the filter constitutes a low-pass filter comprising a filter capacitor element, a filter inductor element, and a matching capacitor element, and the filter capacitor element housed in the resin terminal case serves as a filter inductor element. Connect, the inductor element for the filter is connected to the fitting, the capacitor element for the filter is arranged on the side of the ferrite, and the capacitor element for the filter is the matching capacitor element and the filter in the direction perpendicular to the thickness direction of the ferrite. The inductor element is arranged at a position different from that of the inductor element. The filter capacitor element may be arranged outside the metal case.

With the above structure, the metal fitting for electrically connecting the filter to one of the center electrodes is insert-molded in the resin terminal case, and the matching capacitor element and the filter inductor are provided on the side of the ferrite. Since the filter capacitor element is arranged at a position different from the matching capacitor element and the filter inductor element in the direction perpendicular to the ferrite thickness direction, the filter can be connected via the metal fittings. The non-reciprocal circuit device has a low profile.

Further, it is preferable that the metal case is divided into a plurality of metal case portions, the connecting fitting is made of the same material as the metal case portion, and the metal case portion is insert-molded in the resin terminal case. As a result, the metal case portion and the connecting fitting can be obtained from the integrated component.

Further, the communication device according to the present invention is small in size, inexpensive, and highly reliable by including the nonreciprocal circuit device having the above-mentioned characteristics.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a nonreciprocal circuit device and a communication device according to the present invention will be described below with reference to the accompanying drawings.

[First Embodiment, FIGS. 1 to 6] FIG. 1 is an exploded perspective view of an embodiment of a nonreciprocal circuit device according to the present invention. The non-reciprocal circuit device 1 is a lumped constant isolator. As shown in FIG. 1, a lumped constant isolator 1
Is a center electrode assembly 13 including a ferrite 20 and center electrodes 21 to 23, a resin terminal case 3, a resistance element R, matching capacitor elements C1 to C3, a filter capacitor element C4, and a filter inductor element L. A rectangular permanent magnet 9, a metal upper case (metal case portion) 4 and a metal lower case (metal case portion) 8 are provided.

In the center electrode assembly 13, three center electrodes 21 to 23 are arranged on the upper surface of a rectangular microwave ferrite 20 with an insulating sheet (not shown) interposed so as to intersect each other at approximately 120 degrees. ing. These center electrodes 21 to 2
3 horizontally guides the port portions P1 to P3 on one end side, and makes the common ground electrode 25 of the center electrodes 21 to 23 on the other end side contact the lower surface of the ferrite 20.
The common ground electrode 25 substantially covers the lower surface of the ferrite 20. The center electrodes 21 to 23 and the ground electrode 25 are made of a conductive material, and are integrally formed by punching or etching a thin metal plate.

The lower metal case 8 has left and right side walls 8b and a bottom portion 8a. This metal lower case 8
It is integrally molded with the resin terminal case 3 by the insert molding method. From the pair of opposite sides of the bottom portion 8a of the metal lower case 8, two ground terminals 1 are provided.
6 extends from the bottom 8a. The metal upper case 4 has a rectangular shape in a plan view, and includes the upper portion 4a and the left and right side walls 4a.
b. The metal upper case 4 and the metal lower case 8 are formed by, for example, punching a plate material having a high magnetic permeability such as iron or silicon steel, bending it, and then plating it.

The resin terminal case 3 has a bottom portion 3a and two side portions 3b. A rectangular window portion 3c is formed in the center of the bottom portion 3a, and matching capacitor elements C1 to C3, a filter capacitor element C4, and a resistor element R are housed in the periphery of the window portion 3c, respectively. A recess 3e for accommodating the window 3d and the filter inductor element L is formed. The bottom 8a of the metal lower case 8 is exposed in the windows 3c and 3d. The exposed bottom portion 8a also functions as the ground lead electrode 8a.

The resin-made terminal case 3 has input terminals 14,
The output terminal 15 and the connection fitting 17 are insert-molded. Input terminal 14 (see FIG. 2) and output terminal 15
Has one end exposed on the outer side surface of the resin-made terminal case 3 and the other end exposed on the inner side surface of the resin-made terminal case 3 to serve as an input lead electrode 14a and an output lead electrode 15a. One end of the connection fitting 17 is exposed at the bottom portion 3a of the resin terminal case 3 (see FIG. 3), and the central portion thereof is a filter capacitor element C4.
Is exposed at the bottom of the window 3f in which is stored, and the other end is the side 3b.
Is exposed to the outside (see FIG. 2). The connection fitting 17 formed in the resin terminal case 3 is L-shaped.

Input lead electrode 14 of resin terminal case 3
a, the output extraction electrode 15a, and the connection fitting 17 are formed of the same material and plating as the metal upper case 4 and the metal lower case 8. Metal lower case 8 and terminals 14 ~
By using the same material and the like for 16 and the connecting fitting 17, it is possible to facilitate the automation of manufacturing by the insert molding method and the handling during manufacturing by using the long lead frame. That is, the metal lower case 8 and the terminals 14 to 16 and the connecting fitting 1 which are integrated into the lead frame.
7. The resin-made terminal case 3 can be obtained by forming the resin-made terminal case 3 in 7 by the insert molding method and separating it from the hoop portion of the lead frame. Therefore, the resin-made terminal case 3 can be mass-produced at low cost. In addition, the metal lower case 8, the terminals 14 to 16 and the connection fitting 17 can be firmly fixed to the resin terminal case 3. Therefore, the arrangement position of the connection fitting 17 and the like in the resin terminal case 3 is stable, and a connection failure due to a positional deviation between the connection fitting 17 and the filter capacitor element C4 or between the connection fitting 17 and the port portion P1 is unlikely to occur, which is reliable. The isolator 1 having high property can be obtained. Further, since the metal lower case 8, the terminals 14 to 16 and the connecting fitting 17 can be obtained as one component, the isolator 1 can be made inexpensive.

In the resistance element R, a ground-side terminal electrode and a hot-side terminal electrode are formed on both ends of an insulating substrate by thick film printing or the like, and a resistor is arranged between them.

The matching capacitor elements C1 to C3 and the filter capacitor element C4 have a hot side capacitor electrode (first capacitor electrode) 27 on the entire upper surface and a cold side capacitor electrode (second capacitor electrode) 28 on the entire lower surface.
Are installed.

The filter inductor element L is a copper wire wound with a predetermined outer diameter. The copper wire is covered with an insulating film such as polyimide amide, polyester imide, polyester, or polyimide having excellent heat resistance to electrically insulate the windings. Moreover, the copper wire is exposed at both terminal portions.

The above components are assembled as follows. As shown in FIG. 2, the matching capacitor elements C1 to C3 and the resistor element R are connected to the window portion 3 of the resin terminal case 3.
d, the filter inductor element L is housed in the recess 3e, the filter capacitor element C4 is housed in the window 3f, and the center electrode assembly 13 is housed in the window 3c of the resin terminal case 3.

At this time, the ground electrode 25 formed on the back surface of the ferrite 20 is the bottom portion 3a of the resin terminal case 3.
It is connected to the ground lead electrode 8a through the window portion 3c formed in 1 and is grounded. The port P1 is connected to one of the connecting fittings 17 exposed on the bottom 3a, and the cold side capacitor electrode 28 of the filter capacitor element C4 is connected to the other connecting fitting 17 exposed on the window 3f. To do. One end of the filter inductor element L is connected to the capacitor electrode 27 of the filter capacitor element C4, and the other end is connected to the input lead electrode 14a. That is,
Since the input extraction electrode 14a is connected to the input terminal 14, the port portion P1 is connected to the input terminal 14 through the bandpass filter 30 including the filter capacitor element C4 and the filter inductor element L (FIG. 3).

The hot-side terminal electrode of the resistance element R is
The capacitor electrode 27 on the hot side of the matching capacitor element C3 is connected via the port P3 which is the end of the center electrode 23.
The ground side terminal electrode of the resistance element R is connected to the ground lead electrode 8a exposed in the window 3d of the resin terminal case 3. The hot-side capacitor electrodes 27 of the matching capacitor elements C1 to C3 are connected to the port portions P1 to P3, respectively. Matching capacitor elements C1 to C3
The capacitor electrode 27 on the cold side of is the ground lead electrode 8
a respectively connected to a. That is, the ground lead electrode 8a
Is electrically connected to the ground terminal 16, the matching capacitor element C3 and the resistance element R are electrically connected in parallel between the port portion P3 of the center electrode 23 and the ground terminal 16 ( (See FIG. 5). The connection between the capacitor electrode 27 or the ground electrode 25 and the ground lead electrode 8a or the connecting fitting 17 is performed by a method such as solder reflow. As described above, since the elements C1 to C4, R, and L are directly connected to the ground lead electrode 8a and the connecting fitting 17 in the resin terminal case 3, the assembling cost of the isolator 1 can be reduced.

At this time, the matching capacitor element C1 and the filter capacitor element C4, which are arranged on the side of the ferrite 20, are electrically connected through the connection fitting 17. As a result, the filter capacitor element C4 can be arranged beside the ferrite 20 without overlapping the matching capacitor element C1 and the like. Therefore, the height of the isolator 1 can be reduced.

Further, the metal upper case 4 is mounted from above. A permanent magnet 9 is arranged below the upper portion 4 a of the metallic upper case 4. The permanent magnet 9 is arranged above the ferrite 20 of the center electrode assembly 13 (see FIG. 2) and applies a DC magnetic field to the ferrite 20. Side wall 8b of metal lower case 8 and side wall 4b of metal upper case 4
Has a metal case that is electrically connected by a method such as solder reflow to form a magnetic circuit and also functions as a yoke.

Thus, the isolator 1 shown in FIG. 4 is obtained. FIG. 5 is an electrical equivalent circuit diagram of the isolator 1 shown in FIG. The center electrodes 21 to 23 and the matching capacitor elements C1 to C3 form a nonreciprocal circuit 1a.

In the isolator 1 described above, as shown in FIG. 3, in the bandpass filter 30 in the direction perpendicular to the thickness direction of the ferrite 20, the filter capacitor element C4 and the filter inductor element L are matching capacitors. Since it is arranged at a position different from the elements C1 to C3, the bandpass filter 30 and the matching capacitor element C
1 to C3 can be arranged side by side, and the isolator 1
The thickness of can be reduced. Therefore, the isolator 1 can be downsized and reduced in height.

Since the bandpass filter 30 is provided inside the isolator 1, the electrical characteristics can be improved.

The isolator 1 described above can be modified into an isolator 2 having an electrical equivalent circuit shown in FIG. That is, the isolator 2 shown in FIG.
In the isolator 1 shown in FIG. 3, instead of the filter capacitor element C4, a metal plate 29 having the same outer dimensions as the filter capacitor element C4 is used as the resin terminal case 3.
Of the input terminal 1 while being electrically connected to the port P1 and the inductor element L for the filter by being incorporated in the window 3f of
4 is the same as that in which an external filter capacitor element C5 is connected. However, the filter capacitor element C5 may be housed inside the metal case. In this case, in the direction perpendicular to the thickness direction of the ferrite 20, the filter capacitor element C5 is different from the other element C1.
It is arranged at a position different from C3 and L.

The isolator 2 described above is the nonreciprocal circuit 1a.
A π-type low-pass filter 31 is connected to. Here, the matching capacitor element C1 is included in both the nonreciprocal circuit 1a and the low-pass filter 31. The matching capacitor element C1 also functions as a capacitor element for the π type low-pass filter 31. In other words, the π-type low pass filter 31 is formed by the filter inductor element L, the matching capacitor element C1 and the filter capacitor element C5.

Further, since the port portion P1 and the filter inductor element L are conductor-connected and the filter capacitor element C5 is connected to the outside, the isolator 1 can be commonly used. Therefore, by designing the resin terminal case 3 in common, it is possible to omit the individual die design of the resin terminal case 3.

Since the resin terminal cases 3 used for the isolators 1 and 2 have no mechanical or dimensional difference, the isolators 1 and 2 can be manufactured on the same manufacturing line. Therefore, even if the isolator 1 with the built-in bandpass filter 30 is changed to the isolator 2 with the low-pass filter 31 or vice versa, it is not necessary to change the manufacturing line or change the jig. Since it is possible to almost eliminate the time loss in changing the product, it is possible to establish a low-cost production system that can easily cope with the change in the required quantity.

[Second Embodiment, FIG. 7] In the second embodiment, an embodiment of a communication device will be described by taking a mobile phone as an example.

FIG. 7 is an electric circuit block diagram of the RF portion of the mobile phone 120. 7, 122 is an antenna element, 123 is a duplexer, 131 is a transmission side isolator, 132 is a transmission side amplifier, 133 is a transmission side interstage bandpass filter, 134 is a transmission side mixer, 135 is a reception side amplifier, 136 is Bandpass filter for receiving side interstage, 1
37 is a receiving side mixer, 138 is a voltage controlled oscillator (VC
O) and 139 are local band pass filters.

Here, the isolators 1 and 2 of the first embodiment can be used as the isolator 131. By mounting these isolators 1 and 2,
It is possible to realize a compact and low-cost mobile phone.

[Other Embodiments] The present invention is not limited to the above embodiments, but can be modified into various configurations within the scope of the gist of the present invention. For example, the detailed structure of the metal upper case 4, the metal lower case 8, the resin terminal case 3, the connection fittings 17, etc., which are the components of the isolators 1 and 2, is arbitrary.

Further, although the crossing angle of each of the center electrodes 21 to 23 is described as 120 degrees, it is not limited to this and may be in the range of 110 to 140 degrees. Further, although the metal case has been described as being composed of the metal upper case 4 and the metal lower case 8, the metal case is not limited to this and may be divided into three or more.
Further, the center electrodes 21 to 23 are formed by punching and bending a thin metal plate, or by etching and bending the thin metal plate, or by forming a substrate (dielectric substrate, magnetic substrate or laminated substrate). Etc.) can also be formed by providing a pattern electrode. Further, the shape of the center electrode assembly 13 is not limited to a rectangular shape, but may be a columnar shape, a deformed angular shape, or the like. Further, the shape of the permanent magnet 9 may be, for example, a rectangular shape with rounded corners, a circular shape, or a deformed angular shape other than the rectangular shape.

In addition to the isolator, the present invention can be applied to various non-reciprocal circuit devices such as circulators.

[0041]

As is apparent from the above description, according to the present invention, in the nonreciprocal circuit device, the connection metal fitting for electrically connecting the filter to one of the center electrodes is inserted in the resin terminal case. By molding, at least the matching capacitor element and the filter inductor element can be arranged at different positions in the direction perpendicular to the thickness direction of the ferrite. As a result, since each element can be efficiently arranged in the metal case, it is possible to obtain a non-reciprocal circuit element and a communication device having a small size and a low profile.

[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 the nonreciprocal circuit device shown in FIG. 1 after partial assembly.

3 is a III-III of the non-reciprocal circuit device shown in FIG.
Sectional view.

4 is an external perspective view of the nonreciprocal circuit device shown in FIG. 1 after completion of assembly.

5 is an electrical equivalent circuit diagram of the nonreciprocal circuit device shown in FIG.

6 is an electrical equivalent circuit diagram showing a modified example of the nonreciprocal circuit device shown in FIG.

FIG. 7 is an electric circuit block diagram of a communication device according to the present invention.

FIG. 8 is a plan view of a conventional non-reciprocal circuit device.

FIG. 9 is a plan view of another conventional non-reciprocal circuit device.

[Explanation of symbols]

1, 2 ... Lumped constant type isolator (non-reciprocal circuit element) 3 ... Resin terminal case 4 ... Metal upper case (metal case) 8 ... Metal lower case (metal case part) 9 ... Permanent magnet 13 ... Center electrode assembly 17 ... Connection fitting 20 ... Microwave ferrite 21-23 ... Center electrode 27 ... Capacitor electrode (first capacitor electrode) 28 ... Capacitor electrode (second capacitor electrode) 30 ... Bandpass filter (BPF) 31 ... Low-pass filter (LPF) 120 ... Mobile phone (communication device) C1 to C3 ... Matching capacitor element C4 ... Capacitor element for filter C5 ... Filter capacitor element L ... Inductor element for filter

Claims (7)

[Claims] 1. A center electrode assembly composed of a permanent magnet, a ferrite to which a direct current magnetic field is applied by the permanent magnet, and a plurality of center electrodes arranged on the ferrite, and at least one of the center electrodes. A matching capacitor element electrically connected to the filter, a filter comprising at least a filter capacitor element and a filter inductor element, and one of the filter capacitor element and the filter inductor element of the center electrode. A resin terminal case in which at least the connection fitting for electrically connecting to one, the center electrode assembly, the matching capacitor element, and the filter inductor element are housed, and the connection fitting is insert-molded. And the permanent magnet, the center electrode assembly, and the front part that are assembled in the resin terminal case. A matching metal capacitor and a metal case for accommodating at least the filter inductor element are provided, and at least the matching capacitor element and the filter inductor element are arranged on the side of the ferrite in the thickness direction of the ferrite. In the direction perpendicular to
The nonreciprocal circuit device, wherein the matching capacitor device and the filter inductor device are arranged at different positions. 2. The filter constitutes a bandpass filter including the filter capacitor element and the filter inductor element, and the filter capacitor element housed in the resin terminal case is a first capacitor electrode. And a second capacitor electrode facing the first capacitor electrode, the filter inductor element is connected to the first capacitor electrode, the second capacitor electrode is connected to the connection fitting, and the side of the ferrite is connected. The filter capacitor element is arranged in a position different from the matching capacitor element and the filter inductor element in the direction perpendicular to the thickness direction of the ferrite. The nonreciprocal circuit device according to claim 1, wherein: 3. The nonreciprocal circuit device according to claim 1, wherein the filter forms a low-pass filter including the filter capacitor element, the filter inductor element, and the matching capacitor element. . 4. The filter capacitor element housed in the resin terminal case is connected to the filter inductor element, the filter inductor element is connected to the connection fitting, and the filter is provided on a side of the ferrite. A capacitor element for filter is arranged, and the capacitor element for filter is arranged at a position different from the capacitor element for matching and the inductor element for filter in a direction perpendicular to the thickness direction of the ferrite. The nonreciprocal circuit device according to claim 3. 5. The nonreciprocal circuit element according to claim 3, wherein the filter capacitor element is arranged outside the metal case. 6. The metal case is divided into a plurality of metal case portions, the connection fitting is made of the same material as the metal case portion, and the metal case portion is insert-molded into the resin terminal case. The nonreciprocal circuit device according to any one of claims 1 to 7, wherein 7. A communication device comprising the nonreciprocal circuit element according to claim 1. Description: