HIGH FREQUENCY SWITCH CIRCUIT BUILT IN SWITCH SEMICONDUCTOR INTEGRATED CIRCUIT OR COMMUNICATION TERMINAL DEVICE

摘要

PURPOSE: A high frequency switch circuit built in a switch semiconductor integrated circuit or a communication terminal device is provided to reduce the insertion loss and obtain an excellent high-frequent characteristic by fixing both ends of a cascade circuit of plural FETs and a potential of an intermediate connection point. CONSTITUTION: A first high frequency signal input and output terminal(301) and a second high frequency signal input and output terminal(302) are used for inputting and outputting a high frequency signal therethrough. A cascade circuit of plural FETs(101-104) is arranged between the first high frequency signal input and output terminal and the second high frequency signal input and output terminal. A high level voltage or a low level voltage is selectively applied to the gate terminals of the FETs so that the FETs are switched between an on-state and an off-state. A predetermined voltage is applied to the two end points and the respective intermediate connection points of the cascade circuit of the FETs via each resistor(205-209) separately so that the electric potential is fixed at the two end points and the respective intermediate connection points of the cascade circuit of the FETs.