A voltage converter uses a component such as a JFET or four-terminal power MOSFET having no body diode and exhibiting no body diode conduction characteristic as a synchronous rectifier to reduce switching losses and body diode conduction losses and to support high frequency switching so that use of smaller components and higher current densities can be achieved. These effects are enhanced by a self-driven circuit utilizing positive feedback to enhance switching speed and reduce switching losses which increase with switching frequency.