A resonant switched capacitor based 4-to-1 bus converter achieving 2180 W/in3 power density and 98.9% peak efficiency

Hybrid switched-capacitor (SC) converters are known to have the potential to achieve higher efficiency and higher power density than conventional SC and magnetic-based converters, thanks to the efficient utilization of both active and passive components. By comparing the total switch stress and the minimal passive component volume, the cascaded 2:1 resonant SC topology is found to be excellent for applications with large conversion ratio (e.g. data center power delivery). A 36-60 V input, 4:1 fixed ratio intermediate bus converter is built based on this topology. The prototype achieves 98.9% peak efficiency and up to 2180 W/in
³
power density, both of which are significantly higher than the state-of-the-art.