12 W monolithic X-band HBT power amplifier

Monolithic, two-stage X-band power amplifiers were designed and fabricated using AlGaAs/GaAs heterojunction bipolar transistors (HBTs). Output power levels of up to 12.5 W continuous wave (CW) were demonstrated at 9.2 GHz from single-chip HBT amplifiers measuring 3.8 mm*4.7 mm in size. Two amplifier designs were fabricated using optimized 300- mu m common-emitter unit cells. Device and circuit design aspects of this work are presented along with measured data on the performance of the power amplifiers. The high CW output power level at X-band frequencies highlights the advantages of HBT technology for microwave solid-state power applications.<>