Article ID: 13.20160108
Class-E power amplifiers have found widespread application because of their design simplicity and high-efficiency operation. The nonlinear characteristic of the switching device significantly affects the power amplifier performance, although this is often neglected in theoretical analyses. In this paper, a class-E power amplifier with a shunt capacitance composed of nonlinear and linear capacitance has been mathematically analyzed to obtain the frequency limitation that governs maximum efficiency operation. The analytical method is presented to determine the effective operating frequency for any model of MOSFET device. The practical power amplifier circuit, using a MRF282 MOSFET, was implemented to verify the validity of the theoretical analysis.
