JPH02130001A - Adjusting method for accumulator/isolator - Google Patents

Abstract

PURPOSE:To attain adjustment without spoiling reliability by performing impedance matching by applying resin on a capacitor. CONSTITUTION:The impedance matching is performed by applying the resin on the capacitor 101. Namely, the capacitor 101 is covered with silicone resin 102 (epsilon=3.0). For instance, in a figure where frequency is put on an absissa and insertion loss and isolation are put on an ordinate, f+, f- are the upper and the lower limits of using frequency respectively, and curves shown by full lines are the characteristics of this example, and the curves shown by broken lines are the characteristics of conventional one. Thus, the isolator with the characteristic meeting the using frequency can be constituted. The resin to cover the capacitor fulfills a role to adjust finely the capacity of the capacitor and acts a function to protect the capacitor.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for adjusting an isolator/circulator used in a microwave radio.

(Conventional technology) FIG. 3 is a block diagram of a conventional isolator.

In FIG. 3, 301 is an irreversible element made of garnet and a center conductor, 302 and 303 are strip line terminals, 304 is an electrode, 305 is a capacitor, 306 is a ground electrode, and 307 is a resistor. Also, in Figure 4, the third
An equivalent circuit diagram of the isolator shown in the figure is shown.

The conventional method for adjusting this isolator is to assemble and solder each component as shown in Figure 3, then connect it to a measuring device, measure its electrical characteristics, and then change the applied magnetic field and capacitor capacity. , was making adjustments.

In other words, as explained in FIG. 4, the conventional adjustment method adjusts the impedance of the irreversible element 401 to a predetermined characteristic by changing the applied DC magnetic field, and adjusts the impedance of the non-reciprocal element 401 to a desired characteristic by changing the capacitance of the matching capacitor 402. We are trying to obtain the isolator characteristics that correspond to the following.

(Problem to be Solved by the Invention) When changing the capacitance of this capacitor, the soldered chip capacitor is removed and a chip capacitor with a different capacitance is soldered again. However, since the minimum capacitance pitch of commercially available capacitors is 0.5 pF, it is not possible to finely adjust the capacitance, which has resulted in poor yield. It is also possible to finely adjust the capacitance by cutting the chip capacitor with a diamond or file, but this approach is impractical due to reliability problems.

Furthermore, when removing the chip capacitor, the patterned electrodes of the ceramic substrate tend to peel off, which deteriorates reliability.

In view of the above, the present invention aims to provide a highly reliable and easy adjustment method for isolators and circulators.

(Means for Solving the Problems) The present invention provides an isolator/circulator used in microwave band radio equipment, etc., which is characterized in that impedance matching is achieved by applying resin to a capacitor. This is an adjustment method.

(Embodiment) FIG. 1 is an enlarged view of a capacitor portion of an isolator according to an embodiment of the present invention. In this embodiment, a capacitor 101 is covered with a silicone resin 102 (t = 3.0). Other parts are similar to the conventional example.

A characteristic diagram of this embodiment and the conventional example is shown in FIG.

In FIG. 2, the horizontal axis represents frequency, and the vertical axis represents insertion loss and isolation. In this Figure 2,
f+ and f- are the upper and lower limits of the frequency used, respectively. Moreover, the characteristics shown by the solid line in FIG. 2 are the characteristics of the embodiment of the present invention, and the characteristics shown by the broken line are the characteristics of the conventional example.

According to the present invention, an isolator with characteristics suitable for the frequency used can be constructed.

In addition, the resin covering the capacitor serves to finely adjust the capacitance of the capacitor and to protect the capacitor.

Moreover, although the above description has been made using an isolator, it goes without saying that the same applies to a circulator.

(Effects of the Invention) The present invention allows adjustment of isolators and circulators without impairing reliability, and is useful for improving yield.

[Brief explanation of the drawing]

FIG. 1 is an enlarged view of a capacitor portion of an isolator according to an embodiment of the present invention, and FIG. FIG. 3 is a characteristic diagram of an embodiment of the present invention and a conventional example.
FIG. 4 is a configuration diagram of a conventional isolator, and FIG. 4 is an equivalent circuit diagram of the conventional example. 101... Chip capacitor, 102... Resin,
301, 401... Irreciprocal circuit element, 302, 303
... Strip line terminal, 304 ... Electrode, 30
5,402... Capacitor, 306... Earth electrode, 307... Resistor. Figure 1 Figure 2

Claims (1)

[Claims] A method for adjusting isolators and circulators used in microwave band radio equipment, etc., characterized in that impedance matching is performed by applying resin to a capacitor.