An Improved 48-to-12V Series-Parallel Resonant Switched-Capacitor Converter for Data Center Applications

Switched-capacitor converters (SCCs) are widely used in chip scaled applications, and their resonant alternatives (RSCCs) have been developed for high-power transmission and high efficiency through soft switching. In these topologies, not only the voltage stress, the number of components, but also the conduction loss caused by the current determine whether high efficiency and high-power density can be achieved. This article compares common RSCC topologies and presents an improved Series-Parallel Resonant Switched-Capacitor Converter (SPRC), which has two-phase and split-phase control methods in two variants, which can be potentially used in non-isolated high step-down ratios for data center applications. A 48-to-12 V 600 W converter prototype was built and tested, achieving a peak efficiency of 95.5% with a proper switching device voltage clamping strategy.