GAIN SWITCHING METHOD OF PHASE SHIFTER CIRCUIT, CONTROL CIRCUIT OF PHASE SHIFTER CIRCUIT AND PHASE SHIFTER CIRCUIT

摘要

PROBLEM TO BE SOLVED: To miniaturize a circuit without installing an input terminal for inputting only a control signal from an outer device. SOLUTION: A switching control part 36 generates the control signals DA and DB for selecting a pair of first and second differential amplifiers 32 and 33 or a pair of third and fourth differential amplifiers 34 and 35 based on an input signal Sin. The switching control part 36 generates the control signal DA selecting a pair of first and second differential amplifiers 32 and 33 in the case of the input signal Sin of a first frequency f1. The switching control part 36 generates the control signal DB for selecting a pair of third and fourth differential amplifiers 34 and 35 in the case of the input signal Sin of a second frequency f2.