JPH0652844B2 - Non-reciprocal circuit electronic components - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a nonreciprocal circuit electronic component, and more particularly to a nonreciprocal circuit electronic component such as an isolator or a circulator having a nonreciprocal circuit element to which a DC bias magnetic field is applied. .

(Prior Art) FIGS. 2A and 2B respectively show an example of a conventional isolator as the background of the present invention, FIG. 2A is an illustrative view thereof, and FIG. 2B is an exploded perspective view thereof.

In this isolator 1, a dielectric substrate 4 is connected to a bottom portion 2a in a rectangular parallelepiped metal case 2 via a ground plate 3, an isolator element 5 is inserted into a central hole of the dielectric substrate 4, and a metal case is formed. A permanent magnet 6 is adhered to the inside of the second lid portion 2b so that a DC bias magnetic field is applied from above the isolator element 5.

The isolator element 5 described above has three mesh-shaped center conductors 9 between the pair of ferrites 7 with the insulator sheet 8 interposed therebetween.
Are arranged so as to intersect with each other at an angle of 120 degrees, and the bottom surface of the lower ferrite 7 is joined to the ground plate 3 via the conductor portions 9c integrally formed with the respective center conductors 9. There is. Further, the external lead-out terminal 9b of each center conductor 9 is connected to the impedance matching electrode 4a on the upper surface of the dielectric substrate 4. The cut-and-raised connection pieces 9a are fitted and connected to the fitting pieces 10a of the copper shield plate 10 made of copper. As a result, the shield plate 10 is connected to the ground plate 4 and has the ground potential.

(Problems to be Solved by the Invention) In such a conventional isolator 1, a metal case 2 including a bottom portion 2a and a lid portion 2b is provided to protect the isolator element 5, and the isolator element 5 is further provided with a direct current (DC). Metal case 2 for applying a bias magnetic field
Since the permanent magnet 6 is provided inside, the number of parts is large and the number of assembling steps is also large. Therefore, the cost is high. In addition, since the number of parts is large, it is large. Furthermore, since the isolator element 5 is only covered with the metal case 2 and is not hermetically sealed, the moisture resistance of the isolator element 5 is poor.

Therefore, a main object of the present invention is to provide a non-reciprocal circuit electronic component that can be reduced in cost and size and that has good moisture resistance.

(Means for Solving the Problems) The present invention includes a non-reciprocal circuit element in which ferrites are brought close to a plurality of central conductors, and a molding material containing magnetic powder formed around the non-reciprocal circuit element, A non-reciprocal circuit electronic component in which a molding material is made into a permanent magnet so as to have a residual magnetic flux inside, and the residual magnetic flux of the molding material is applied as a bias magnetic field to the non-reciprocal circuit element.

(Function) Since the molding material is formed around the non-reciprocal circuit element,
The non-reciprocal circuit element is sealed and protected by a molding material.

Further, the residual magnetic flux inside the permanent magnetized molding material is applied to the nonreciprocal circuit element as a bias magnetic field.

(Effect of the Invention) According to the present invention, the nonreciprocal circuit element is sealed and protected by the molding material made into a permanent magnet, and the bias magnetic field is applied to the nonreciprocal circuit element. A metal case for protection and a permanent magnet for applying a bias magnetic field are unnecessary. Therefore, the number of parts is reduced and the number of assembling steps is also reduced. As a result, the cost can be reduced. Further, since the number of parts is reduced, the size can be reduced. Moreover, since the specific reversible circuit element is sealed by the molding material, the moisture resistance is improved.

The above-mentioned objects, other objects, features and advantages of the present invention will become more apparent from the following detailed description of the embodiments with reference to the drawings.

(Embodiment) FIGS. 1A to 1D respectively show an embodiment of the present invention, FIG. 1A is a perspective view thereof, FIG. 1B is a sectional view thereof, and FIG. FIG. 1D is an exploded perspective view of the inside, and FIG. 1D is an illustrative view showing a residual magnetic flux of a molding material. In this embodiment, an isolator will be described as an example of a non-reciprocal circuit electronic component, but it should be pointed out in advance that the present invention can be applied to other non-reciprocal circuit electronic components such as a circulator other than an isolator.

The isolator 11 includes an isolator element 12 as a non-reciprocal circuit element, and the isolator element 12 is inserted into a hole 15 in the center of a dielectric substrate 14. Further, the three central conductors 12a, 12 of the isolator element 12 are
b and 12c are electrodes 14a, 1 on the dielectric substrate 14.
4b and 14c, respectively. Further, the electrodes 16 a and 14 b on the dielectric substrate 14 are connected to the terminal 16
a and 16b are respectively connected. Therefore, these terminals 16a and 16b are connected to the electrodes 14a and 1b.
It is electrically connected to the isolator element 12 via 4b.

A ground plate 18 is provided below the dielectric substrate 14. An electrode 20 is formed on the lower surface of the isolator element 12 so as to extend from the central conductors 12a to 12c. Therefore, the ground plate 18 is electrically connected to the center conductors 12a to 12c via the electrode 20.

On the other hand, a shield plate 22 is provided on the isolator element 12.
The shield plate 22 is attached to the center conductor 12
a to 12c. Therefore, the shield plate 22 is set to the same potential as the ground plate 18.

Further, a molding material 24 containing magnetic powder is formed around the isolator element 12 and the dielectric substrate 14 described above.

In this case, as the material of the molding material 24, for example, a thermosetting resin such as epoxy or DAP, or PA or P is used.
For a resin such as a thermoplastic resin such as PS, a material containing magnetic powder such as ferrite or a rare earth element is used. Then, the isolator element 12 and the dielectric substrate 1
The molding material 24 is formed by putting a combination of 4 and the like in a molding die and sealing and molding with a material containing magnetic powder in the above resin. Therefore, the isolator element 12 is sealed by the molding material 24.

Further, this molding material 24 has, for example, a first B
By applying a magnetic field in the downward direction as shown by arrow A in the figure or in the upward direction as shown by arrow B, the permanent magnet is made to have a residual magnetic flux. In this case, for example,
If a magnetic field is applied in the upward direction to make the mold 24 a permanent magnet as shown by an arrow B in FIG.
As shown in FIG. D, it is made into a permanent magnet so as to have a downward residual magnetic flux therein. Therefore, a DC bias magnetic field is applied to the isolator element 12 by the molding material 24 made into a permanent magnet. The molding material 24
May be made into a permanent magnet when the isolator element 12 or the like is molded by sealing with the material.

In this isolator 11, the isolator element 12 is hermetically sealed and protected by the molding material 24 made into a permanent magnet, and a bias magnetic field is applied to the isolator element 12. Therefore, as compared with the conventional example, a metal case for protection and A permanent magnet for applying a bias magnetic field becomes unnecessary.

Moreover, since this isolator 11 is sealed by the molding material 24, it can be used as a surface mount component.

BRIEF DESCRIPTION OF THE DRAWINGS FIGS. 1A to 1D respectively show an embodiment of the present invention, FIG. 1A is a perspective view thereof, FIG. 1B is a sectional schematic view thereof, and 1C. The figure is an exploded perspective view of the inside thereof, and FIG. 1D is an illustrative view showing the residual magnetic flux of the molding material. 2A and 2B respectively show an example of a conventional isolator as the background of the present invention, FIG. 2A is an illustrative view thereof, and FIG. 2B is an exploded perspective view thereof. In the figure, 11 is an isolator, 12 is an isolator element, and 24 is a molding material containing magnetic powder.

Claims (1)

[Claims] 1. A non-reciprocal circuit element comprising ferrites arranged in proximity to a plurality of central conductors, and a molding material containing magnetic particles formed around the non-reciprocal circuit element, wherein the molding material contains residual magnetic flux. A non-reciprocal circuit electronic component, which is made into a permanent magnet so that the residual magnetic flux of the molding material is applied to the non-reciprocal circuit element as a bias magnetic field.