Numerical design of current-fed DC-RF inverter operating at 2 MHz

The operation of the MOSFET DC-RF power inverter of the current-fed type is analyzed. The change of the MOSFET on-resistance with the gate-source voltage was used to build an equivalent circuit of the inverter, and simultaneous differential equations for the equivalent circuit were solved using the Runge-Kutta-Gill method. The calculated output voltage waveform agreed well with that obtained by experiment. The effects of the gate-drain capacitance, gate-source capacitance, and gate-source drive impedance on the output voltage waveform were considered as well as the power loss of the inductor at the output. The DC input current, DC input power, RF output voltage peak, RF output power, and power efficiency were calculated in terms of the temperature dependence of the on-resistance