DC-DC CONVERTERS

摘要

A single ended forward converter comprises a primary switch, a transformer having a primary winding coupled in series with the primary switch to supply voltage terminals and a secondary winding coupled via a rectifying and smoothing circuit to output voltage terminals, and a series-connected first inductor and auxiliary switch coupled in parallel with the primary switch. Leakage inductance between the primary and secondary windings, which may be supplemented by an inductive component in series with one of the windings, resonantly couples energy to a capacitance in parallel with the primary switch, the energy being recovered, when the auxiliary switch is open, via a second inductor inductively coupled to the first inductor. Control signals for the switches are timed to provide substantially zero voltage switching of the primary switch to provide high efficiency. The converter also provides for resetting of the transformer in each switching cycle.