LARGE-SIGNAL, POWER MOSFET SWITCHING TIMES IN PWM, ZERO-CURRENT-SWITCHED AND ZERO-VOLTAGE-SWITCHED DC DC CONVERTERS

The large signal switching times of MOSFETs in pulse-width modulated (PWM), zero-current-switched and zero-voltage-switched DC/DC converters contribute to higher losses at increased frequencies of operation. These switching times determine the high frequency limits of the converters. Simple and analytical expressions for these switching times are obtained and the results are verified against SPICE simulations. The important effect of the non-linear drain-to-source capacitance is accounted for. The expressions derived are design oriented, providing the switching times directly from the parameters of the device and its application.