JPS6114168Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a circulator with a wide band.

Conventionally, as shown in FIG. 1, a stripline forming a center conductor 1 is provided on a ferrite 2, one end of the stripline is grounded together with a shield case 3 covering the ferrite 2, and the other end of the stripline is grounded together with a shield case 3 covering the ferrite 2. A circulator is known in which a series circuit of a capacitor 5 and a coil 6 is inserted between the input/output terminal 4 and the input/output terminal 4 to achieve a wide band. Incidentally, in recent years, with the miniaturization of microwave equipment, there has been a demand for miniaturization of non-reciprocal circuit elements such as circulators. Therefore, input/output terminal 4
If ordinary elements were used as the frequency adjustment capacitor 7, capacitor 5, coil 6, etc. between the shield case 3 and the shield case 3, the overall shape would be large, so miniaturization of these parts became a problem. There is.

In view of the above points, the present invention provides a compact, wideband circulator with excellent mass production by forming a stripline as a center conductor and a series circuit of capacitors and coils for widening the band on the same insulating substrate. This is what I am trying to do.

Embodiments of the broadband circulator according to the present invention will be described below with reference to the drawings.

2 to 4 show embodiments of the present invention in which a broadband circulator is constructed. In these figures, the center conductor portion 1A is connected to the insulating substrate 1.
A stripline 11 and a series circuit of a capacitor 12 and a coil 13 for widening the band are formed on one side of the 0 using thick film technology. This center conductor portion 1A
A ferrite 2 is disposed above and below the ferrite 2, and a shield case 3A is further attached to cover the ferrite 2. Those ferrites 2 have a permanent magnet 1
4 applies a DC magnetic field to each.

Now, in the center conductor portion 1A, a slit 15 for mounting the shield case 3A is formed in advance in an insulating substrate 10 made of alumina or the like so as to pass through the substrate, and a strip is first formed on one side of the insulating substrate 10. Conductor film 1 in the shape of dividing the line 11 into two
6A, lower capacitor electrode 1 for forming capacitor 12
7A and the lower conductor film 18A for forming the coil 13 are formed by screen printing and baking a metal paste such as gold or silver. Next, an insulator film 21 having a connection hole 20 at a position corresponding to the tip 19A of the conductor film 16A is formed on the conductor film 16A by screen printing and baking a dielectric paste such as glass. . At the same time, an insulating film 23 having connection holes 22 at positions corresponding to the ends of the lower conductive film 18A is used to screen a dielectric paste such as glass onto the lower capacitor electrode 17A and the lower conductive film 18A. It is formed by printing and baking. Then, a conductor film 16B, which is the remaining half of the stripline 11 and has a capacitive electrode 24 for frequency adjustment, is formed on the insulating substrate 1 by screen printing and baking a metal paste.
0 and the insulating film 21. At the same time, an upper capacitor electrode 17B for forming the capacitor 12 and an upper conductor film 18B for forming the coil 13 are formed on the insulator film 23 by screen printing and baking a metal paste. Here, since the tip 19A of the conductor film 16A is exposed in the connection hole 20 of the insulator film 21, the tip 19A of the conductor film 16A and the tip 19B of the conductor film 16B are exposed during the formation of the conductor film 16B. are connected to each other to form a stripline 11 having a capacitive electrode 24 at each end. Further, at this time, the conductor film 16B and the lead-out portion 25 of the lower capacitor electrode 17A overlap, and the two are electrically connected. The insulator film 2
Since the end of the lower conductor film 18A is exposed in the connection hole 22 of No. 3, the upper capacitor electrode 17 is exposed when forming the upper capacitor electrode 17B and the upper conductor film 18B.
Connection between B and lower conductor film 18A and lower conductor film 1
8A and the upper conductive film 18B, a series circuit of a capacitor 12 and a coil 13 is formed for widening the band, and the non-grounded end of the stripline 11 is input/output via this series circuit. The terminals 28 are respectively drawn out. On the other hand, on the other surface of the insulating substrate 10, a ground electrode 26 is formed by screen printing and baking a metal paste so as to face the capacitive electrode 24 outside the portion where the ferrite 2 is located. In this way, the three sets of striplines 11 as central conductors, the frequency adjustment capacitance between the capacitance electrode 24 and the ground electrode 26, and the capacitance connected to the non-grounded end of each stripline. 12
A central conductor portion 1A having a series circuit of the coil 13 and the coil 13 is completed.

Disc-shaped ferrites 2 are arranged above and below the central conductor portion 1A, respectively, so as to sandwich the center conductor portion 1A. The shield case 3A integrally has a mounting leg 27 that fits into the slit 15, and the upper and lower shield cases 3A are inserted and fixed into the mounting slit 15 of the central conductor board 1A while covering and holding the ferrite 2. and solder the strip line 1.
1 and the ground electrode 26 .

According to the above embodiment, the following effects can be achieved.

(1) A series circuit of a capacitor 12 and a coil 13 for widening the band is inserted between the non-grounded end of the strip line 11 forming the center conductor and the input/output terminal 28, so that the band can be widened. can be achieved.

(2) Since the capacitor 12 and the coil 13 for widening the band are formed on the insulating substrate 10 using thick film technology like the stripline 11, miniaturization is possible. In particular, the coil 13 is connected to the lower conductor film 1.
Since the coil is divided into the upper conductor film 18A and the upper conductor film 18B, and the two conductor films are connected through the connection hole 22 of the insulator film 23, the folding pitch can be made smaller than when making a coil with a single layer structure. The substrate area can be reduced.

(3) The conductive films 16A, 16B and the insulating film 21 are formed on one side of the insulating substrate 10 using thick film technology, and since the insulating film 21 is thin, the connection hole 2 of the insulating film 21 is formed on one side of the insulating substrate 10.
It is easy to connect the conductor films 16A and 16B through the wire. Therefore, it is possible to easily form a stripline and obtain a circulator with excellent mass productivity.

(4) Between the capacitive electrode 24 for frequency adjustment integrally formed at the end of the stripline 11 on one side of the insulating substrate 10, which is a dielectric, and the ground electrode 26 on the other side of the insulating substrate 10, A capacitor for frequency adjustment can be formed. Therefore, there is no need to externally attach a frequency adjustment capacitor between the input/output terminal 28 and the ground, allowing for miniaturization, and it is easy to obtain the same characteristics when mass-produced.

In the above embodiment, a circulator is shown, but it is clear that an isolator can be constructed by providing a terminating resistive film as a terminator between one of the input/output terminals 28 and the ground.

In addition to thick film technology, thin film technology can also be used.

As mentioned above, according to the present invention, a stripline as a center conductor and a series circuit of capacitors and coils for widening the band of a multilayer film structure using film fabrication technology are formed on the same insulating substrate. So,
To obtain a compact, wideband circulator with excellent mass productivity.

[Brief explanation of the drawing]

FIG. 1 is an equivalent circuit diagram showing a basic broadband circulator, FIG. 2 is a perspective view showing an embodiment of the broadband circulator according to the present invention, FIG. 3 is an exploded perspective view of the center conductor in the embodiment, and FIG. The figure is a perspective view showing the back side of the center conductor section. 1...Center conductor, 1A...Center conductor part, 2...
Ferrite, 3,3A...Shield case, 10
...Insulating board, 12...Capacity, 13...Coil,
14...Permanent magnet, 16A, 16B, 18A, 1
8B... Conductor film, 17A, 17B, 24... Capacitor electrode, 21, 23... Insulator film, 26... Earth electrode, 28... Input/output terminal.

Claims (1)

[Scope of utility model registration request] A lower capacitor electrode 17A and a lower conductor film 18A are formed on an insulating substrate on which a stripline as a center conductor is provided, and an insulator having a connection hole 22 at a position corresponding to the end of the lower conductor film 18A. A film 23 is formed on the lower capacitor electrode and the lower conductor film, and an upper capacitor electrode 17B facing the lower capacitor electrode and an upper conductor film connected to the lower conductor film are formed on the insulator film 23. By forming 18B,
A broadband circulator comprising a series circuit of a capacitor and a coil connected to the non-grounded end of the stripline.