In accordance with the concepts, circuits and techniques described herein, a converter circuit is provided having multiple half-bridge switching cells that can be selectively controlled using one or more switching patterns to convert a source voltage to a desired output voltage over wide voltage and power ranges while maintaining zero-voltage switching and/or zero-current switching. The convert circuit includes capacitive elements disposed between center switching nodes of the half-bridge switching cells and fixed potentials and a magnetic energy storage element coupling the center switching nodes of first and second half-bridge switching cells. A controller is coupled to the converter circuit to monitor, control and apply one or more switching patterns the half-bridge switching cells such that components of the half-bridge switching cells are switched having a minimal or zero voltage (or current) across them.