High-frequency electronic switch, and burst wave generating device using the same and short range radar using the same

Abstract

A high-frequency electronic switch includes a signal input terminal to which a high-frequency signal to be switched is input, a plurality of amplifying circuits with transistors, to respectively amplify the high-frequency signal to be switched sequentially, the amplifying circuits being cascade-connected in a plurality of stages to the signal input terminal, a signal output terminal which is connected to an output section of an amplifying circuit at final stage among the plurality of amplifying circuits, and which outputs the high-frequency signal to be switched sequentially amplified, a control terminal to which a pulse signal serving as a switching signal having a period of a first level and a period of a second level is input, and a supply current control circuit which makes the plurality of amplifying circuits be in an amplification-operational state by supplying operational current to each of the transistors of the plurality of amplifying circuits in a period when the pulse signal input to the control terminal is at the first level, and which makes the plurality of amplifying circuits be in a non-amplification-operational state by stopping supplying operational current to each of the transistors of the plurality of amplifying circuits in a period when the pulse signal is at the second level. The high-frequency electronic switch effectively suppresses leakage of high-frequency signal at the time of off-state by turning on/off between the signal input terminal and the signal output terminal so as to be able to be isolated substantially high-frequency likewise in accordance with a level of the pulse signal input to the control terminal.