Design and Implementation of GaN-HEMT Based High-Efficient 4MHz Full-Bridge Class-DE Power Amplifier

The Class-DE resonant inverter has enormous potential in high-power radio-frequency (RF) applications due to limited voltage stress and zero-voltage switching (ZVS) capability of power devices. To realize high-efficient and high-power RF generation, this paper proposes a GaN-HEMT based full-bridge class-DE power amplifier (PA) with an output L-S impedance conversion network. Harmonic suppression, ZVS of GaN-HEMTs as well as output power enhancement are simultaneously realized. Simulation results verify the proposed topology and parameter design approach. Experimental results on a 207.4 W prototype prove that it can achieve 98.5 % efficiency at 4 MHz output frequency and 50 -Ohms load.