X-band GaN high power amplifier with integrated power switch for airborne applications

This paper reports an X-Band High Power Amplifier (HPA) integrated with a power switch demonstrated for the first time in a 0.25 μm GaN process. The power switch and its drivers are implemented in a synchronous buck converter topology with off-chip filters to modulate the drain supply. The designed supply modulator is then combined with X-band GaN HPA on the same die and the integrated system is experimentally measured as a function of power and frequency. The measured PAE of the combined HPA and supply modulator is 26.8% at a drain voltage of 20 V while delivering maximum output power 35 dBm.