A 48-V:16-V, 180-W Resonant Switched-Capacitor Converter With High-Q Merged Multiphase LC Resonator

Hybrid-resonant switched-capacitor (SC) converters have gained traction as a way to increase efficiency and power density in high conversion ratio dc-dc applications. However, there is still room to improve passive component utilization and performance by exploiting resonant behavior and the unique circuit networks in hybrid topologies. This article explores a nominally 3:1 step-down resonant SC dc-dc converter that uses a high-Q multiphase LC resonator. The resonator combines flying capacitors and inductor(s) into a single component, leveraging advantages of each to improve the performance (efficiency and power density) of the overall structure. A hardware prototype is presented that achieves over 97% efficiency at >100 W in a 48-V:16-V step-down configuration. The prototype is used to highlight an interesting direction for future research in intermediate-bus converters for data center applications.