Design of symmetric class-EM power amplifier

This paper presents a novel class-E_M power amplifier for low harmonic contents and high output power. In the proposed class-E_M power amplifier, the symmetric configuration is applied to the class-E_M power amplifier. By applying the symmetric configuration, the proposed class-E_M power amplifier obtains the extremely low total harmonic distortion and four times higher output power than the conventional single class-E_M power amplifier. For achieving the class-E_M ZVS/ZDVS/ZCS/ZDCS conditions, the MOSFET drain-to-source nonlinear parasitic capacitances, finite dc-feed inductance, equivalent series resistances of inductors, and switch-on resistances are considered in the circuit designs. A design example is presented along with the PSpice-simulation and experimental waveforms at 3.5 MHz operating frequency. The waveforms from the PSpice-simulations and circuit experiments agreed with the numerical predictions quantitatively, which validates the effectiveness of the proposed class-E_M power amplifier in this paper.