JP2002271110A - Nonreciprocal circuit element and communications equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a nonreciprocal circuit element in which the end face of a surface-mounted input/output terminal can be covered sufficiently with solder and the mounting strength can be increased by forming a solder fillet, when the circuit element is mounted on the surface of a printed circuit board, etc., and to provide communications equipment. SOLUTION: The surface-mounted input/output terminal 54 is extended from the hooped material of a lead frame and constituted by coating a base material, composed of a magnetic metal containing iron as the main ingredient with a metal coating film having solder wettability. The terminal 5 is cut off from the lead frame in a prescribed assembling step. The cut face 54b of the terminal 54 is formed to have a height H lower than the thickness T of the terminal 54 and to have a width W2 narrower than that W1 of the terminal 54. In addition, the cut face 54b is positioned on the top side of the end face of the terminal 54.

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 used in a microwave band, and a communication device.

[0002]

2. Description of the Related Art Conventionally, a lumped constant type isolator employed in a mobile communication device such as a cellular phone is shown in FIG.
The following has been proposed. The isolator 141
Includes a resin terminal case 143, a metal lower case 144, and a metal upper case 148, in which a permanent magnet and a center electrode assembly (not shown) are accommodated.

The side wall 1 on the front side of the resin terminal case 143
43a, an input / output terminal 154 for surface mounting and two ground terminals 156 are provided. Although not shown, an input / output terminal and two ground terminals are provided on a side wall 143a on the inner side of the resin terminal case 143. The ground terminals 156 extend from the near side and the far side of the bottom wall of the lower case 144, respectively. On the other hand, input / output terminal 1
54 is a resin terminal case 1 together with the lower case 144.
43 is insert-molded.

Incidentally, in the case of non-reciprocal circuit elements such as isolators, a long lead frame (a long lead frame covered with a metal film having solder wettability) is used in order to facilitate the production automation and the handling during the production. It is manufactured using base material: iron). The reason why the base material of the lead frame is made of iron is that the lower case 144 made of metal (iron) and the upper case 148 made of metal (iron) and the permanent magnet made of the same material as the lead frame, and the permanent magnet are used as a magnetic material as a closed magnetic circuit. Is formed. The lead frame is sequentially transported through each of the assembling steps by using the pilot holes provided in the pair of hoop portions. While the lead frame is sequentially conveyed through each assembly process, the input / output terminal 154 and the lower case 144 extending from the pair of hoop portions of the lead frame are insert-molded into the resin terminal case 143, and the isolator 141 is formed. Are attached, and the isolator 141 is assembled. The isolator 141 is separated from the lead frame by punching out and cutting the connection between the input / output terminal 154 and the lower case 144 and the lead frame with a die. FIG.
In the figure, the portions 144a and 154a indicated by oblique lines are cut surfaces with the lead frame.

[0005]

However, in the conventional isolator 141, since the entire end surface of the surface mounting input / output terminal 154 is a cut surface 154a from the lead frame,
Iron as a base material of the input / output terminal 154 is exposed on the entire end face. For this reason, there is a problem that iron exposed on the end face of the input / output terminal 154 is rusted and reliability is reduced.

Further, since iron has poor solder wettability, when the isolator 141 is surface-mounted on the electrode patterns 161 to 163 of the printed circuit board 170 as shown in FIG. , Solder 165
Is not formed, and the mounting strength of the isolator 141 is reduced. Since the base material (iron) is not exposed on the end surface of the ground terminal 156, a fillet of the solder 165 is formed.

In order to improve the mounting strength of the isolator 141, if the width of the electrode pattern 161 is increased by increasing the size of the input / output terminal 154, the solder fillet 1
Although the width W of the electrode 65 increases, the gap between the electrode pattern 161 and the electrode pattern 162 is reduced, so that a bridge (short) due to the solder for mounting is likely to occur, or a substrate ground electrode formed on the back surface of the printed circuit board 170. There is also a problem that the stray capacitance formed between the electrode 175 and the electrode pattern 161 increases and the frequency characteristic of the isolator 141 changes.

Also, since the two input / output terminals 154 are unevenly distributed on one side of the isolator 141, if the bonding strength of the solder fillet 165 of the input / output terminal 154 is weak and the input / output terminal 154 comes off, the other input / output terminal 154 will come off. The load of the holding force acting on the ground terminal 156 unevenly distributed on one side of the terminal increases, and eventually, there is a problem that all the terminals are peeled off.

Accordingly, an object of the present invention is to provide an end face of an input / output terminal for surface mounting that can be covered with solder sufficiently and short-circuited with other terminals when the surface is mounted on a printed circuit board or the like. Another object of the present invention is to provide a non-reciprocal circuit device and a communication device capable of increasing a mounting strength by forming a solder fillet.

[0010]

In order to achieve the above object, a nonreciprocal circuit device according to the present invention comprises: (a) a permanent magnet; and (b) a center electrode to which a DC magnetic field is applied by the permanent magnet. An assembly, (c) a metal case accommodating the center electrode assembly, which is separated from the lead frame, and (d) a metal case, separated from the lead frame.
A surface mounting input / output terminal electrically connected to the center electrode assembly and extending in a horizontal direction from a bottom side of the metal case; and (e) the surface mounting input / output terminal and the metal. The case is covered with a metal film having solder wettability except for the cut surface with the lead frame, and the height of the cut surface of the input / output terminal for surface mounting with the lead frame is set at the height for surface mounting. The thickness is smaller than the thickness of the output terminal, and the cut surface is arranged on the upper side of the end surface of the input / output terminal for surface mounting.

Further, the non-reciprocal circuit device according to the present invention comprises:
(F) a permanent magnet; (g) a center electrode assembly to which a DC magnetic field is applied by the permanent magnet; and (h) a metal case that is separated from the lead frame and houses the center electrode assembly. i) surface mounting input / output terminals that are electrically connected to the center electrode assembly that is separated from the lead frame, and are led out horizontally from the bottom side of the metal case; The surface mounting input / output terminals and the metal case are covered with a metal film having solder wettability except for a cut surface with the lead frame. The height of the cut surface is smaller than the thickness of the surface mounting input / output terminal, and the cut surface is disposed above the end face of the surface mounting input / output terminal, and the width of the cut surface is For mounting Smaller than the width of the output terminal, characterized by.

Here, the input / output terminals for surface mounting and the metal case preferably have a thickness of 0.1 mm or more and are made of a material containing iron as a main component. It is preferable that the input / output terminals for surface mounting and the metal case are integrally molded with resin.

With the above configuration, when the nonreciprocal circuit element is surface-mounted on the printed circuit board, the cut surface of the surface mounting input / output terminal having poor solder wettability is located on the upper side of the end surface of the surface mounting input / output terminal, that is, The part that is placed away from the printed circuit board and covered with a metal film with good solder wettability is placed at a position close to the printed circuit board, so it is covered with a metal film with good solder wettability. A solder fillet having a sufficient height is formed on the end face of the input / output terminal for surface mounting.

Further, the non-reciprocal circuit device according to the present invention is characterized in that the input / output terminals for surface mounting are separated by a cutting blade that cuts from the bottom side to the upper side of the non-reciprocal circuit device. When the cutting blade shears the joint between the surface mount I / O terminal and the lead frame from the bottom side of the irreversible circuit element to the top side, the solder wettability covering the bottom surface of the surface mount I / O terminal is reduced. The metal film having the metal film is spread so as to cover the base material exposed on the cut surface of the input / output terminal for surface mounting. Therefore, the height of the portion where the base material is exposed further increases, and the height of the solder fret formed on the end surface of the surface mounting input / output terminal further increases.

Further, the communication device according to the present invention has high reliability by being provided with the non-reciprocal circuit device having the above-described characteristics.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of a nonreciprocal circuit device and a communication device according to the present invention will be described with reference to the accompanying drawings. Although the embodiments are described using a lumped-constant isolator as an example, it goes without saying that the embodiments can also be applied to a circulator and the like.

[First Embodiment, FIGS. 1 to 10] As shown in FIG. 1, a surface mount type isolator 41 is generally composed of a lower metal case 44, a resin terminal case 43, and a center electrode. An assembly 53, a metal upper case portion 48, a permanent magnet 49, an insulating member 47, a resistance element R, and matching capacitor elements C1 to C3 are provided.

In the center electrode assembly 53, the center electrodes 61 to 63 are interposed on the upper surface of a rectangular plate-shaped microwave ferrite 60 with a substantially rectangular insulating sheet 66 (indicated by a dotted line) interposed therebetween. They are arranged so as to cross each other so that the corners are approximately 120 degrees.

The center electrodes 61 to 63 have port portions P1 to P3 at one end, and the ground electrode 65 at the other end.
Is connected. The ground electrode 65 common to the center electrodes 61 to 63 is provided so as to substantially cover the lower surface of the ferrite 60. The center electrode assembly 53 is configured such that the ground electrode 65 formed on the back surface of the ferrite 60 is connected to the resin terminal case 4.
3 through a window 43c, is connected to the bottom wall 44b of the lower metal case 44 by soldering or the like, and is grounded.

In the resin terminal case 43, surface mounting input / output terminals 54 and 55 and a metal lower case portion 44 are insert-molded. Metal lower case part 44
Has left and right side walls 44a, a bottom wall 44b, and four surface-mounting ground terminals 56 each extending two from the front side and the back side of the bottom wall 44b. The surface mounting ground terminals 56 are respectively led out from the opposing side walls 43 a of the resin terminal case 43. That is, the ground terminal 56 for surface mounting is led out from the bottom side of the lower case part 44 in the horizontal direction. One end of each of the input / output terminals 54 and 55 for surface mounting is led out from the opposite side wall 43 a of the resin terminal case 43, and the other end is exposed to the bottom 43 b of the resin terminal case 43. Output lead electrode portions 54a and 55a (see FIG. 5) are formed. That is, the surface mounting input / output terminals 54 and 55 are led out from the bottom side of the lower metal case 44 in the horizontal direction. Input / output extraction electrode unit 54
Port portions P1 and P2 are soldered to a and 55a, respectively.

In the matching capacitor elements C1 to C3, the metal capacitors having the hot-side capacitor electrodes soldered to the port portions P1 to P3 and the cold-side capacitor electrodes exposed at the window portion 43d of the resin terminal case 43 are provided. Each is soldered to the bottom wall 44b of the side case portion 44.

The resistance element R is soldered on the circuit board 58. One of the resistance elements R is connected to a matching capacitor element C via a signal pattern provided on the circuit board 58.
3 is connected to the hot side capacitor electrode, and the other is connected to the bottom wall 44b of the metal lower case portion 44 exposed at the window 43d of the resin terminal case 43. That is, the matching capacitor element C3 and the resistance element R are connected to the center electrode 63.
Is electrically connected in parallel between the port portion P3 and the ground (see FIG. 4).

In the resin terminal case 43, a center electrode assembly 53, matching capacitor elements C1 to C3, a resistance element R, and the like are accommodated, and a metal upper case portion 48 is mounted from above. A permanent magnet 49 and an insulating member 47 are disposed between the upper metal case 48 and the center electrode assembly 53. The permanent magnet 49 applies a DC magnetic field to the center electrode assembly 53. The metal lower case part 44 and the upper case part 48 are joined to form a metal case, constitute a magnetic circuit, and also function as a yoke. The metal upper case portion 48 is formed, for example, by punching a plate made of soft iron, bending the plate, and then plating the surface with copper or silver. Thus, the isolator 41 shown in FIG. 3 is obtained. FIG. 4 is an electrical equivalent circuit diagram of the isolator 41 shown in FIG.

In the isolator 41 having the above configuration, as will be described later in detail, the surface mounting input / output terminals 54 and 55 and the metal lower case portion 44 extend from a pair of hoop members of the lead frame. Each of them is made of a material in which a magnetic metal mainly composed of iron is used as a base material and the base material is covered with a metal film having solder wettability. The surface mounting input / output terminals 54 and 55 and the metal lower case portion 44 are separated from the lead frame in a predetermined assembly process. In FIG. 1, a portion 44c indicated by oblique lines is a cut surface between the metal lower case portion 44 and the lead frame.

On the other hand, in FIG. 2, a portion 54b indicated by oblique lines is a cross section of the input / output terminal 54 for surface mounting and the lead frame. Although not shown, the same applies to the cut surface between the surface mounting input / output terminal 55 and the lead frame. The cut surface 54b of the surface mounting input / output terminals 54 and 55 has a height dimension H smaller than the thickness T of the surface mounting input / output terminals 54 and 55 and a width W2 of the surface mounting input / output terminals 54 and 55. , 55 smaller than the width W1 and the cut surface 54
b is arranged on the upper side of the end faces of the input / output terminals 54 and 55 for surface mounting.

Therefore, as shown in FIG. 3, this isolator 41 is connected to the electrode pattern 161 of the printed circuit board 70.
163, the lower end surface 54f of the cut surface 54b of the surface mounting input / output terminals 54 and 55 (that is, the portion where the base material mainly composed of iron is exposed) due to the viscosity of the solder. Solder fillet 16 (see FIG. 2)
5 can be formed, and the mounting strength can be increased. Further, in the isolator 41 before mounting, since the area of the base material exposed at the end faces of the surface mounting input / output terminals 54 and 55 is small, the anticorrosion effect (rust prevention) of the base material can be obtained.

In the isolator 41 having the above-described structure, the long lead frame 11 shown in FIG. 5 is used in order to automate the production and facilitate the handling during the production.
It is manufactured using. The lead frame 11 is made of a base metal 20 made of a magnetic metal mainly composed of iron.
With a metal coating 21 having a function of improving the anticorrosion property and the adhesion strength of the metal coating (plating) on the surface as a base,
It is covered with a metal film 22 having solder wettability (see FIG. 9). For example, soft iron is used for the base material 20, and copper or nickel is used for the metal film 21 (typical film thickness: 3 μm) which has an anticorrosion property and a function of improving the adhesion strength of the metal film (plating) on the surface, Copper, silver or gold is used for the metal film 22 having solder wettability (typical film thickness: 5 μm).

The pair of elongated hoop portions 13 of the lead frame 11 are provided with pilot holes 13 at predetermined intervals.
a is provided. At the tips of the support portions 15 and 16 extending inward from the pair of hoop portions 13, respectively, a metal lower case portion 44 of the isolator 41 and surface mounting input / output terminals 54 and 55 are integrally provided. ing. Further, between the pair of hoop portions 13, a plurality of bars 14 are bridged at predetermined intervals. This lead frame 11
After punching and bending the base material 20, it is formed by plating the surface with copper, silver, or the like.

FIG. 6 is an enlarged view of a connection portion between the surface mounting input / output terminal 54 and the support portion 16. The thickness H (see FIG. 9) of the connecting portion 54c between the surface mounting input / output terminal 54 and the support portion 16 is set to be smaller than the thickness T (see FIG. 9) of the surface mounting input / output terminal 54, and The width is also set smaller than the width of the surface mounting input / output terminal 54. The connecting portion 54c is arranged on the upper surface side of the surface mounting input / output terminal 54. The connecting portion between the surface mounting input / output terminal 55 and the supporting portion 16 also has the same structure.

The lead frame 11 has a pilot hole 13
Each assembly process is sequentially conveyed using a. First, after setting the lead frame 11 in a resin mold, a resin terminal case 43 is formed by injection molding a resin as shown in FIG. At this time, the metal lower case portion 44 and the surface mounting input / output terminals 54 and 55 are integrally insert-molded into the resin terminal case 43. As a result, the metal lower case portion 44 and the surface mounting input / output terminals 54 and 55 are firmly fixed to the resin terminal case 43, and the flatness of the bottom surfaces of the terminals 54 to 56 is improved. A structure advantageous for is obtained. Also, by integrating the resin terminal case 43 with the metal lower case portion 44 and the like, the number of components and the number of manufacturing steps can be reduced.

The surface mounting input / output terminals 54, 5
In order to arrange the cut surface of No. 5 as far as possible from the printed circuit board 70 and to form the solder fillet 165 more reliably, it is preferable to set the thickness H of the connecting portion 54c as thin as possible. However, if the thickness is too small, the strength of the connecting portion 54c is reduced, and problems such as the cutting of the connecting portion 54c during the formation of the resin terminal case 43 occur. Therefore, in the first embodiment, as shown in FIG. 8, the surface mounting input / output terminals 54, 5
A part of the connecting portion 54c and a part of the supporting portion 16 are cut off.
However, FIG. 8 shows the input / output terminal 5 for surface mounting as a representative.
Only four are shown. Hereinafter, FIG. 9 and FIG. 10 are the same. Specifically, as shown in FIG. 9, the fixed blade 80 of the cutting die is connected to the upper surfaces 54 of the input / output terminals 54 and 55 for surface mounting.
After pressing against d, the cutting blade 81 is raised vertically, that is, moved from the bottom side to the top side of the isolator 41 to shear the connecting portion 54c.

As a result, as shown in FIG. 10, the metal films 21, 22 covering the bottom surfaces of the surface mounting input / output terminals 54, 55 are exposed on the cut surface 54b of the surface mounting input / output terminals 54, 55. The covering portion 71 is formed so as to cover the base material 20 that is being covered. That is, lead frame 1
1 is covered with the metal film 22 having solder wettability except for the cut surface 54b. Therefore, in the cut surface 54b, the height h1 from the bottom surface 54e to the portion where the base material 20 is exposed can be increased. As a result, it is possible to form the solder fillet 165 reliably and at a high position on the end surfaces of the surface mounting input / output terminals 54 and 55 without reducing the strength by making the thickness H of the connecting portion 54c extremely thin. it can.

Thereafter, the center electrode assembly 53, the resistor R, and the matching capacitor C are placed in the resin terminal case 43.
1 to C3, an insulating member 47 and a permanent magnet 49 are accommodated, a metal upper case portion 48 is attached from above, and an isolator 41 is assembled. The isolator 41 connected to the lead frame 11 is separated from the lead frame 11 by punching and cutting a pair of support portions 15 (see FIG. 8) with a die. At this time, the cut surface 44c (see FIG. 3) with the support portion 15 is exposed on the side wall 43a of the resin terminal case 43. That is, it is covered with the metal film 22 having solder wettability except for the cut surface 44c with the lead frame 11. However, since the cut surface 44c does not significantly affect the mountability, electrical characteristics, and environmental resistance of the isolator 41, exposure of the base material 20 at the cut surface 44c is not a serious problem.

In the first embodiment, the thickness T of the surface mounting input / output terminals 54 and 55 and the metal lower case portion 44 is set to 0.1 mm. Further, the thickness H of the connecting portion 54c needs to be 0.04 to 0.06 mm or more. Thickness H
Is smaller than this, the manufacturing process of the lead frame 11, that is, punching and bending the base material 20,
This is because the connecting portion 54c is cut in the step of plating the surface.

Therefore, the surface mounting input / output terminals 54 and 55
Is 0.1 (= the thickness of the metal lower case portion 44) is 0.1
If it is not less than mm, the height of the solder fillet 165 is not less than 0.04 mm (= the thickness T of the surface mounting input / output terminals 54 and 55-the thickness H of the connecting portion 54c). That is, if the thickness T of the surface mounting input / output terminals 54 and 55 is greater than 0.1 mm, the height of the solder fillet 165 is reduced to 0.0.
It can be larger than 4 mm. On the other hand, if the thickness T of the surface mounting input / output terminals 54 and 55 is smaller than 0.1 mm, the thickness H of the connecting portion 54c cannot be reduced, so that the height of the solder fillet 165 is reduced. The mounting strength (drop impact resistance and peel strength) required for the surface mount component cannot be obtained.

[Second Embodiment, FIG. 11] In a second embodiment, a mobile phone will be described as an example of a communication device according to the present invention.

FIG. 11 is an electric circuit block diagram of the RF portion of the mobile phone 120. In FIG. 11, 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, and 136 is a reception side amplifier. 137 is a reception-side mixer, 138 is a voltage controlled oscillator (VCO), and 139 is a local band-pass filter.

Here, as the transmitting side isolator 131, the lumped constant type isolator 41 of the first embodiment can be used. By mounting the isolator 41, a highly reliable mobile phone can be realized.

[Other Embodiments] The non-reciprocal circuit device and the communication device according to the present invention are not limited to the above-described embodiment, but can be variously modified within the scope of the gist.

For example, as shown in FIG. 12, the cut surface 5 of the surface mounting input / output terminals 54 and 55 with the lead frame 11 is formed.
4b may have a width W2 equal to the width W1 of the surface mounting input / output terminal 54.

In the above-described embodiment, the metal lower case portion 44 and the surface mounting input / output terminals 54 and 55 are insert-molded into the resin terminal case 43, and then the surface mounting input / output terminals 54 and 55 and the leads are connected. Although the frame 11 is separated, the lead frame 11 may be separated from the surface mounting input / output terminals 54 and 55 after the assembly of the isolator 41 is completed.

[0042]

As is apparent from the above description, according to the present invention, the height of the cut surface of the surface mounting input / output terminal with respect to the lead frame is larger than the thickness of the surface mounting input / output terminal. When the non-reciprocal circuit device is surface-mounted on a printed circuit board or the like, the end surface of the surface-mounting input / output terminal is small and the cut surface is arranged on the upper side of the end surface of the surface-mounting input / output terminal. A solder fillet having a sufficient height can be formed. Therefore, the mounting strength of the non-reciprocal circuit device can be increased. The same effect can be obtained when the width of the cut surface of the input / output terminal for surface mounting and the lead frame is smaller than the width of the input / output terminal for surface mounting. As a result, a highly reliable communication device can be obtained.

[Brief description of the drawings]

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

FIG. 2 is an enlarged perspective view of a surface mounting input / output terminal.

FIG. 3 is a perspective view showing a mounted state of the non-reciprocal circuit device shown in FIG. 1;

FIG. 4 is an electrical equivalent circuit diagram of the non-reciprocal circuit device shown in FIG.

FIG. 5 is a perspective view showing a lower metal case portion extending from a lead frame and input / output terminals for surface mounting.

FIG. 6 is an enlarged perspective view showing a connecting portion between a surface mounting input / output terminal and a lead frame.

FIG. 7 is a perspective view showing a state in which a metal lower case portion and surface mounting input / output terminals are insert-molded in a resin terminal case.

FIG. 8 is a perspective view showing a state where input / output terminals for surface mounting are separated from a lead frame.

FIG. 9 is a sectional view showing a procedure for disconnecting the surface mounting input / output terminal from the lead frame.

FIG. 10 is an exemplary sectional view showing a procedure following FIG. 9;

FIG. 11 is a block diagram showing an embodiment of a communication device according to the present invention.

FIG. 12 is an enlarged perspective view showing a modification of the input / output terminal for surface mounting.

FIG. 13 is a perspective view showing a mounting state of a conventional non-reciprocal circuit device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 ... Lead frame 13 ... Hoop part 22 ... Metal coating with solder wettability 41 ... Isolator 43 ... Resin terminal case 44 ... Metal lower case part 48 ... Metal upper case part 49 ... Permanent magnet 53 ... Center electrode set Solid 54, 55: Surface mounting input / output terminal 54b: Cut surface 54d: Top surface of surface mounting input / output terminal 54e: Bottom surface of surface mounting input / output terminal 71: Covering portion 81: Cut blade 120: Mobile phone H: Cutting Surface height dimension T: Thickness of input / output terminals for surface mounting W1: Width of input / output terminals for surface mounting W2: Width of cut surface

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) // B23K 101: 36 B23K 101: 36

Claims (7)

[Claims] 1. A permanent magnet, a center electrode assembly to which a DC magnetic field is applied by the permanent magnet, a metal case that is separated from a lead frame and houses the center electrode assembly, and is separated from the lead frame. And a surface mounting input / output terminal electrically connected to the center electrode assembly, and led out in a horizontal direction from a bottom side of the metal case. A metal case is covered with a metal film having solder wettability except for a cut surface with the lead frame, and a height dimension of the cut surface with the lead frame of the surface mounting input / output terminal is for surface mounting. A non-reciprocal circuit element, characterized in that the thickness is smaller than the thickness of the input / output terminal, and the cut surface is disposed above an end face of the surface mounting input / output terminal. 2. A permanent magnet, a center electrode assembly to which a DC magnetic field is applied by the permanent magnet, a metal case separated from the lead frame and housing the center electrode assembly, and separated from the lead frame. And a surface mounting input / output terminal electrically connected to the center electrode assembly, and led out in a horizontal direction from a bottom side of the metal case. A metal case is covered with a metal film having solder wettability except for a cut surface with the lead frame, and a height dimension of the cut surface with the lead frame of the surface mounting input / output terminal is for surface mounting. A thickness of the input / output terminal is smaller than a thickness of the input / output terminal; Nonreciprocal circuit device that features a Ri small. 3. The nonreciprocal circuit according to claim 1, wherein the input / output terminal for surface mounting and the metal case are made of a material containing iron as a main component. element. 4. The non-reciprocal circuit device according to claim 1, wherein the surface mounting input / output terminal and the metal case are integrally molded with a resin. . 5. The surface mounting input / output terminal is cut off by a cutting blade that cuts from a bottom side to a top side of the non-reciprocal circuit device. Irreversible circuit element. 6. The irreversible device according to claim 1, wherein the input / output terminal for surface mounting and the metal case have a thickness of 0.1 mm or more. Circuit element. 7. A communication device comprising at least one non-reciprocal circuit device according to claim 1.