Three switch cell soft-switching resonant buck converter for point-of-load application

For high frequency point-of load (PoL) application, conventional hard-switched PWM converters are less efficient for a large voltage conversion ratio compared to resonant converters which inherits soft-switching property. This paper presents a resonant buck converter which has only three switches and provides good efficiency for a large voltage step-down ratio at 1MHz switching frequency. Unlike conventional resonant topologies, no transformer is used in this case to obtain minimum possible footprint. Also a sampled-data model of the converter is derived instead of conventional state-space model as power is transferred at switching frequency. Detailed steady-state analysis of the converter along with simulation and experimental results are presented in this paper.