A new type of high-frequency high-efficiency resonant DC/DC converter is proposed, analyzed, and verified experimentally. It is called a class-E converter because it consists of a class-E inverter and a class-E rectifier. The class-E rectifier acts as an impedance inverter and is compatible with the class-E inverter. Consequently, the converter can operate with load resistances from a full load to infinity while maintaining zero-voltage switching of the transistor in the inverter and the diode in the rectifier. It operates safely with a short circuit at the output. Because of a high value of the load quality factor Q/sub 1/, a narrow frequency range suffices to regulate the DC output voltage over the whole load range. The measured relative bandwidth was delta f/f/sub min/=42.2% as the load resistance was varied from 70 Omega to open circuit. The measured efficiency at the full load was 89% with a 9 W output power at 1 MHz. A family of class-E/sup 2/ resonant DC/DC power converters is given. The possibility of reduction of class-E/sup 2/ converters to lower-order resonant and pulse-width-modulation converters is shown. >