A circuit for reducing power loss for a soft switching full bridge
converter at light loads and enabling very high frequency operation
without using a cold plate approach. The circuit preferably includes a
resonant inductor and blocking inductor on the converter's primary side
arranged so as to provide reduced losses for a zero voltage switching
bridge converter. The circuit provides these benefits even for converters
having a power transformer with very low leakage inductance. The circuit
is not dependent on the presence of a high leakage inductance for the
power transformer. The circuit can also be used in soft switching half
bridge converters. The circuit can also be used in a hard switching full
bridge or half bridge converter for achieving zero voltage switching at
reduced cost with reduced losses at light load, if the duty cycle of the
converter is set near fifty percent.