JPS59196603A - Semiconductor phase shifter - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION This invention tri, a path of a microstrobe 9-tube set constructed on the same semiconductor substrate, using a field effect transistor (hereinafter abbreviated as FET) constructed on a semiconductor substrate such as silicon or GaAa as a switch. This is similar to a semiconductor phase shifter that changes the phase of the micro branch by switching the phase shifter.

Figure 1 shows an example of the structure of a conventional semiconductor phase shifter.

In the figure, (1) is a semiconductor substrate, (2) is a ground conductor, (
3) Fi (a strip conductor that together with 21 constitutes a microstrip line; (4) is an i- conductor consisting of two FETs;
1 5PDT switch, (5) is also the 2nd 5PUT
Switch (61#: drain electrode of jFBT, (7) is gate electrode f8 of PET) Source electrode of triFET. In addition, in order to apply a gate bias voltage to the gate electrode (7) of FB'l', a bias circuit (II) (i: via the bias terminal 02) consisting of a high impedance line (9) and a low inheatance line υQ )
A bias voltage is applied from In addition.

For FET switch operation, the drain and source voltages of the FET are made to have the same potential in terms of direct current, so the drain electrode and source electrode are usually grounded.

In the figure, illustration of the two via circuits for this purpose is omitted.

Figure 2 is a factor for explaining the operation of the conventional semiconductor phase shifter shown in Figure 1. In the figure, 03) is the main line of the microstrip line, 041 is the 3'1 branch line with electrical length θ1, and US+ is the second branch line with electrical length θ2. Now, if the drain voltage and source voltage are set to the same DC potential, for example OV, then the gate voltage is cut to Ov and the pinch-off voltage (by increasing the percentage).

A micro-branch between the drain electrode (6) and source electrode (8) of the FET performs a switching operation for passing and cutting off the current. Therefore, the drain 1i' pole of two PETs is arranged in common, and the gate bias voltage of one is set to OV.
If the other is set to a pinch-off voltage and the bias is simultaneously switched to the other bias voltage, a single-pole double-throw switch (hereinafter abbreviated as 5PDT switch) can be formed.

In FIG. 2, the electric current 1g! propagating through the main line f131! is the first (y) 5PDT s(y ち(4J, ':A
' It passes through the 5PDT switch (5) of the I (7) branch line (141, 72).Here, switch the 2-car 5PDT switch and switch the radio wave propagation path to the second branch line (151 side). The phase of the cage is determined by the difference in electrical length of the path Δθ(
==62-01), the phase shifter is constructed.

This semiconductor phase shifter is connected to O.1 and second branch line 11.
Since the amount of phase shift is determined by the difference in the length of 4J a5), a highly positive phase shift amount characteristic can be obtained by accurately machining the dimensions of the strip conductor (3). However, the disadvantage was that the insertion loss was large because the radio waves passed through the two '1 PDT switches required to switch the propagation path.

In order to solve this problem, the present invention connects all the FET switches in series between the two microstrike 9 lines, and connects the source electrode and drain electrode of the PET with a length of approximately 1/2 branch length. This is an attempt to obtain a low-loss 180' phase shifter by connecting a branch line consisting of Microst9+Wi[, and connecting the drain electrode of an FET switch whose source electrode is grounded to the middle of the branch line. The drawings will be explained in detail below.

E. Figure 3 shows one implementation of this invention 1+! If: Show. F
The first single-pole single-throw switch a6) (hereinafter 5
A drain electrode (6) and a source electrode (8) of a PST switch (abbreviated as PST switch) are connected to a nine-lag element (3) constituting an input/output microstrip line, and.

The drain electrode (6) and source electrode (8) are approximately I
They are connected by a strip ring body (3) constituting a microst 9-tooth line with a length of A-branch length, and a source electrode (8) is further located approximately in the middle of the strip conductor (3).

A second 8PST grounded via a via hole (not shown), etc.
This is a configuration in which the drain electrode of switch a71 is connected.

FIG. 4 is a diagram illustrating the operation of the present invention.

Both electrodes of the 5PST switch (16) are connected to the main line (LAL, which serves as an input/output line), and a branch line QIU having a branch length of x72, and one electrode is grounded at approximately the middle position of the two branch lines q birch. 5PST switch aη is connected.

In Fig. 4(a), the gate bias of PET is set to the pinch-off voltage, and the 5PST switch (1
ω and aη are in a blocked state. Therefore, the main line 0
The radio waves propagating through 3) come to propagate via branch lines 0 to .

On the other hand, in Fig. 4(b), the FET gate is set to <IAS or OV, and the 5PST switch (lbL
Qη is in a conductive state. Therefore, 5TST
The drain electrode (6) and source electrode (8) of the switch 06] when looking at the branch line Oal side have high impedance, that is, the interrupter is in an open state, and the electric branch is the branch line! ;80S) 8P8T switch 0 without being affected by
ωt=encounter.

Therefore, 5PST switch α61. (By switching the dart bias of the FFT constituting 1η from the pinch-off voltage to OVK, the propagation phase of the current is 180
degree, and a 180 degree phase shifter can be constructed.

In a semiconductor phase shifter with this configuration, the electric current I& is lt'ET
Just by passing through the 5 PAT switch consisting of -1.

A 180 degree phase shift can be obtained, and the insertion loss can be reduced to nearly 1/2 compared to the conventional case of passing through two switches.

Note that the source electrode of two or more STS'l' switches aη (8
Although the case where the ground leakage occurs due to the 1I'i via rule (not shown) has been described, the present invention is not limited to this, and is shown in FIG. As in other embodiments, a strip conductor (191) having a length of approximately 172 drum lengths may be connected at one end to the source electrode (8) and at the other end to the gold conductor (2).
As in the other embodiments shown in Figure 6, the number of axes at the tip is approximately 1.
/4a long strip conductor (4) All source electrodes (
8).

As described above, in the semiconductor phase shifter according to the present invention, an FET switch is connected in series between two microstrip lines constituting an input/output line, and the distance between the source electrode and the drain electrode of the FET is approximately 1. By connecting a branch line with a length of /2 branches and connecting the drain electrode of an FET switch whose source electrode is all grounded roughly in the middle of the branch line, one branch FiFET switch can be installed. By simply passing through, a 180 degree phase shifter can be constructed and a low loss phase shifter can be obtained.

[Brief explanation of the drawing]

21 is a diagram showing an example of the structure of a conventional semiconductor phase shifter, FIG. 2 is an explanatory diagram of the operation of FIG. 21, and FIG. 3 is a diagram showing an example of the structure of the semiconductor phase shifter according to the present invention. FIG. 4 is an explanatory diagram of the operation of the semiconductor phase shifter shown in the third factor,
5 and 16 are diagrams showing the structure of other embodiments of the semiconductor phase shifter according to this invention. In the figure, (l semiconductor substrate, (2) is the base plate, (3) is the stop tap conductor, (4) is the first 5PDT switch, (5)
is the 5PDT switch of 2.2, and (6) is the drain electrode of the FET. (7) is the gate electrode of FET, and (8) is the source electrode of PET. (9) is high impedance & iN, (iur is a low inheatance line, 01) is a bias circuit, and u is a bias terminal. a3) is the 111M path, a's are the first branch lines, u5) are the second branch lines, yi is the single pole single throw switch, αη is the single pole single throw switch, and group 0 is the branch line. Railroad, (]!I
) is a strip conductor with a length of 1/2 length, (support)) is
It is a strip conductor with a length of 1/4ffJ. Note that the same or corresponding parts in the two figures are indicated by the same reference numerals. Agent Masumaru Oiwa

Claims (1)

[Claims] In a semiconductor phase shifter consisting of a microstripe line formed on a semiconductor substrate and a field effect transistor formed on the same semiconductor substrate as the semiconductor substrate, the source electrode of one field effect transistor is , a microstrip line serving as the input and output lines is connected to each of the drain electrodes. Further, the source electrode and the drain electrode are connected by a branch line consisting of a microstrip line having a length of approximately 1/2 wavelength, and the source electrode is grounded at a point of approximately V2 length of the branch line. The drain electrodes of the second field effect transistor are all connected. A semiconductor phase shifter comprising means for applying an Iasumi pressure to the gate electrodes of each of the first and second field effect transistors.