A High Performance Monolithic GaAs SPDT Switch

A monolithic SPDT GaAs FET switch covering DC to 4 GHz has been developed with RF performance comparable to high performance PIN diode designs. Insertion loss of 0.8 dB from DC to 4GHz and isolation of 35 dB at 1.5GHz have been achieved. The MMIC incorporates four 1×1200um FETs in a series-shunt configuration with airbridge interconnects on a chip with overall size of 0.6×0.6mm.