A DC-DC converter circuit includes a transformer with a resonate filter or snubber connected at a primary side and a switch for controlling operation of the converter. A secondary side of the transformer includes self-driven synchronous rectifiers and an output filter. Transistors are provided at the gates leads of the rectifiers and themselves are provided with a fixed voltage at their gates so as to clamp the peak voltages across to the rectifiers.
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.
