JPH0158706B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Technical Field of the Invention The present invention relates to improvements in MIC circuits (microwave integrated circuits) that are used in the construction of various microwave devices and are equipped with so-called double-plane circuits.

(b) Background of the technology A MIC circuit with a so-called double plan view is constructed by forming a microstrip line on the front surface of a dielectric substrate such as ceramic, and a slot line for electromagnetic coupling with the strip line on the back surface. Since it has the advantage of simplifying the circuit configuration and miniaturizing it without requiring a special DC blocking circuit, it is being put into practical use in phase modulators, mixers, converters, and the like.

As an example, FIG. 1 shows a MIC circuit equipped with a double-plane circuit configured as a two-phase phase modulator, with a perspective view A and a plan view B of the back side of the board. 2 and a straight line 3 are provided on the surface of the substrate, and microstrip lines 2 and 3 on the front surface are formed on the metal vapor deposited surface provided on the entire back surface.
The vapor-deposited metal on the portions constituting the slot lines 4 and 5 that face and bridge the two is peeled off by patterning.

The slot line consists of a linear slot line 4 that faces orthogonally to the microstrip line 2 on the substrate surface, and a loop-shaped slot line 5 that faces the microstrip line 2, and a beam lead is installed near the forked joint. The diodes 6 and 7 are connected as shown in the figure with their polarities reversed, and the input signals of the wavelength λ applied to the line 2 are connected to each other depending on the polarity of the signal applied to the baseband signal relay terminal 8. As is known, the signals are taken out from the line 3 in opposite phases. Reference numeral 9 indicates a metal carrier that accommodates and fixes the substrate 1.

In a phase modulator or a frequency converter using a double-plane circuit configured in this way, electrical characteristics due to variations in the specific capacitance of the diodes 6 and 7 or deviations in their mounting positions (phase and frequency converters due to variations in the former) In order to improve the amplitude deviation, the conversion loss due to the latter deviation, and the NF value), post-adjustment is always necessary, and therefore a configuration that facilitates this adjustment work is desired.

(c) Prior art and problems Conventionally, the above adjustment was carried out by placing one or more dielectric pieces 10 on the slot line 4 or 5, or on A and 5 at the same time, and moving the positional relationship between them. After adjusting the characteristics to the desired position, it was fixed using adhesive, etc., but this method was complicated and not suitable for mass production, and since it had to be done from the back side of the ceramic substrate 1, the metal carrier 9 required a fairly large hole. 11 is required. Further, there is a drawback that adjustment work from the back side tends to cause unexpected damage to the minute diodes 6 and 7.

Also, because of this essential punch hole 11, a box-shaped case must be used for hermetic sealing in the final step of the product.

(d) Purpose of the Invention The present invention overcomes the above-mentioned conventional drawbacks and enables adjustment from the surface of the board. Therefore, after connecting the baseband signal transmission wire to the relay terminal 8, hermetic sealing can be easily performed. The purpose is to provide a MIC circuit with high performance.

(e) Structure of the Invention The object of the present invention is to provide a plurality of connecting lands on the surface of the substrate, each forming a pair of connecting lands for providing a bridge line facing the slot line on the back side of a double-plane circuit and perpendicular to the line. The configuration of the present invention is provided in
This is accomplished by a MIC circuit.

By appropriately connecting the paired lands provided on the front surface, the slot line on the back surface is equivalently bridged with inductance, and the capacitance of the diode used is canceled. The value of the inductance is adjusted by the number of land connections. Since this adjustment work is performed from the surface, there is no danger of directly touching the beam lead diode, and the adjustment of the high frequency characteristics can be significantly simplified.

Based on this principle, it is also applicable to, for example, a four-phase phase modulator or an image cancel type frequency converter.

(f) Embodiment of the Invention The gist of the present invention will be specifically explained below using an embodiment shown in FIG.

Figure 2 is a plan view from the surface of an example in which the present invention is implemented in a MIC circuit equipped with a double-plane circuit configured as a two-phase phase modulator shown in Figure 1, and is the same subject as Figure 1. show something

As shown in FIG. 2B, the surface of the ceramic substrate 1, which is placed and fixed on a metal carrier 9' having a hole for accommodating the back cover 16, has an L-shaped line 2 as shown in FIG.
A straight line 3 is provided, and slot lines 4 and 5 are provided on the back side, and a beam lead diode is similarly connected in the vicinity of the pin-shaped coupling portion of the line.

A plurality of connecting lands 1 each forming a pair for providing a bridge line 13 orthogonal to the slot line 5 at a position facing the slot line 5 with the ceramic substrate 1 in between.
4, 14' are provided. If you use fine gold wire or gold ribbon as a bridge line,
This is advantageous because it can be easily connected by thermocompression bonding.

For example, the amplitude and phase deviations shown by the dotted lines in FIG. 3 caused by variations in the characteristics of the beam lead diodes used or variations in the mounting positions may be caused by one or more land pairs 14,
The line 13 bridging the line 14' is adjusted to the normal characteristics shown in the actual battle shown in the figure.

(g) Effects of the Invention As explained above, in the case of the double-plane line according to the structure of the present invention, the characteristics of the slot line on the back side can be determined from the front side, so there is no risk of damaging minute diodes, and the work is easy. In addition to significantly improving performance, it also has the structural effect of allowing the metal carrier to be used as a bottom plate when sealing the MIC circuit.

[Brief explanation of drawings]

Figure 1 shows the configuration of a two-phase phase converter as an example of a MIC circuit equipped with a double-plane circuit in a perspective view A and a plan view B of the back side of the board, and Figure 2 A shows a two-phase phase modulator to which the present invention is applied. FIG. 3 shows an example of the electrical characteristics of the two-phase phase converter before (dotted line) and after adjustment (solid line). In the figure, 1 is a ceramic substrate, 2 and 3 are microstrip lines, 5 is a slot line, and 6 and 7 are
is a beam lead diode, 9 and 9' are metal carriers, 10 is a small dielectric piece, 11 is a hole in the metal carrier, 12 is a hole with a step, 13 is a bridge line, and 14 and 14' are a pair of connection lands. , 15 is a connecting wire, and 16 is a back cover.

Claims (1)

[Claims] 1 In a double-plane circuit with a microstrip line on the front side of the board and a slot line on the back side,
1. A MIC circuit characterized in that a plurality of connecting lands are provided on the surface of a substrate, each pair forming a bridge line facing a slot line on the back side and perpendicular to the line.