Series-Resonator Buck Converter—Viability Demonstration

Abstract

The series-capacitor buck converter doubles the duty ratio, and equalizes the current between two phases. A series-resonator buck converter is realized by adding a resonant tank in series with the series capacitor C <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">s</sub> . All switches turn on at zero voltage, and the low-side switches turn off at zero current. The resonant tank generates additional loss and increases the voltage stress of the low-side switches. A 2-MHz prototype with a peak efficiency of 98.5%, 48 V at the input and 7 V, 20 A at the output was built to demonstrate the viability of the topology.