An analysis of operation of a modified inverse class E power amplifier is presented. The proposed amplifier that has a series tunable parallel resonant tank is similar to a hybrid of class F and inverse class E. The principles and design equations required to determine the optimum operation of the amplifier are analyzed in detail. The practical circuit using LDMOS MRF21010 is shown to be able to deliver 40.02 dBm outpout power at 155 MHz. The amplifier achieves power-added efficiency (PAE) of 78.18% and drain efficiency of 78.42%, and exhibits 25.02 dB power gain when operates from a 21 V supply voltage. Comparisons of simulated and measured results are given with good agreement between them being achieved.
