A microwave high-power GaN transistor with highly-integrated active digital switch-mode driver circuit

An inverter-based digital switch-mode driver circuit, highly-integrated with a GaN power transistor is presented. The layout is fully scalable in output power and therefore suitable for amplifiers with power levels of higher than 10 W. The circuit enables a switch-mode operation from DC to 3 GHz. A consistent analysis of digital switching measurements and active harmonic load-pull results is performed. Measurements at 2 GHz and 30 V yield a drain efficiency of 82 % and 6 W of output power, while a gain up to 35 dB and more than 76 % overall circuit efficiency were achieved.