Soft-switched square-wave half-bridge DC-DC converter

A constant-frequency zero-voltage-switched square-wave dc-dc converter is introduced, and results from experimental half-bridge implementations are presented, A nonlinear magnetic element produces the advantageous square waveforms, and provides isolated terminals from which the output voltage may be controlled. Semiconductor stresses and losses are minimized both by the square waveforms and by low switching losses. The active switches and the output rectifiers both exhibit zero-voltage switching. The active switches (metal-oxide-semiconductor field-effect transistors (MOSFETs)) are operated at a fixed frequency with 50% duty cycle, which allows the use of a simple open-loop gate drive. Experimental implementations verify predicted operation.