A SiGe H-bridge switching amplifier for class-S amplifiers with clock frequencies up to 6 GHz

This paper describes the design of the first voltage-mode switching amplifier in a fast complementary SiGe-technology in the GHz-range. The amplifier is intended as a driver stage for a high power GaN amplifier in a class-S system. It can be operated with pseudo-random digital pulse trains up to 6 Gbit/s. The efficiency of the switching stage is about 57% for a rectangular drive signal with a 50% duty cycle and a frequency of 3 GHz. The amplifier including the drivers shows a PAE of 33%. The broadband output power of the pulse train is about 105 mW.