Abstract: A low power loss boost converter of the discontinuous conduction type includes an inductor coupled between the boost converter input and a junction, a current rectifier coupled between the junction and the converter output, a switch coupled between the junction and common, and a switch capacitor coupled in parallel with the switch, the inductor and an energy storage capacitance associated with the input. The switch is alternately opened and closed in switching cycles which alternately energize the inductor and transfer the energy to the output load. Power losses are reduced by providing switch closure at a near zero voltage and current switch conditions produced by a circuit resonance. The capacitor reduces voltage across the switch during the switch open transient condition.