Analysis of Class-DE PA Using MOSFET Devices With Non-Equally Grading Coefficient

The design and analysis of a new operation-mode of the class-DE power amplifier (PA) using two MOSFETs with the non-equal grading coefficient is introduced. The PA uses the optimum shunt capacitance for each MOSFET to achieve zero voltage switching (ZVS) condition and wide range for the load-resistance point of view. As compared with the conventional class-DE PA, this configuration has low value of the series inductance that is reduced the power dissipation. A design procedure with intuitive curves is obtained that are implemented using a different grading coefficient for two MOSFETs. These criteria prepared an effective approach regardless of the fixed shunt capacitance for achieving ZVS condition. The desired operation of the class-DE PA is guaranteed by converging of design parameters and required output power. Moreover, non-similar switches provide reduced switch power dissipations and the number of the driving circuit PA. The simulation and experiment results are approved by implementing the outlined theoretical relationships for a fabricated class-DE PA at 4-MHz switching frequency and obtained 12.1-W output power.