VARIABLE ACTIVE INDUCTOR CIRCUIT OF MICROWAVE MONOLITHIC INTEGRATED CIRCUIT

摘要

PURPOSE: A variable active inductor circuit of a microwave monolithic integrated circuit(MMIC) is provided to have a low serial resistance and a high Q value by reducing a signal loss in an ultra high frequency band. CONSTITUTION: A variable active inductor circuit of an MMIC includes a first field effect transistor(FET1), a second field effect transistor(FET2) connected to the first field effect transistor(FET1), a first stabilized feedback capacitor(C2) connected between a gate of the first field effect transistor(FET1) and a drain of the second field effect transistor(FET2), a variable resistor(R2) connected to the first stabilized feedback capacitor(C2) in serial and connected to the drain of the second field effect transistor(FET2) and a second stabilized feedback capacitor(C1). One end of the second stabilized feedback capacitor(C1) is connected a connecting node(201) between the first stabilized feedback capacitor(C2) and the variable resistor(R2) and the other end of the second stabilized feedback capacitor(C1) is connected to a connecting node(203) between the source of the first field effect transistor(FET1) and a gate of second field effect transistor(FET2).