Class E/sup 2/ narrow-band resonant DC/DC converters

A family of seven class E/sup 2/, narrowband, high-frequency, high-efficiency, resonant DC/DC converters is introduced, and an experimental example is given. Class E zero-voltage-switching operation of both the inverter and rectifier components is maintained for loads ranging from a full load to an open circuit, significantly reducing switching losses and yielding high efficiency at high frequencies. Because of a high loaded quality factor Q, the current in a resonant circuit is sinusoidal and the output voltage is very sensitive to the operating frequency. Therefore, narrowband FM control of the output voltage is achieved as the load varies from a full load to an open circuit. The measured frequency range Delta f/f/sub min/ was only 20.9% for load resistance from 30 Omega to infinity. The circuits have high power density and fast dynamic response, produce low electromagnetic interference (EMI) and noise, and operate safely with a short circuit at the output. The relationship between pulse width-modulated (PWM) converters and resonant converters is shown. The class E/sup 2/ converters are especially suitable for applications in measurement instrumentation. >