1 MHz multi-resonant push-pull 48 V VRM

Abstract

For future high-end server and workstation applications, it will be impractical for voltage regulator modules (VRMs) to draw power from the 12 V output of the silver box because the voltage bus will be too low to deliver the increasing high levels of power. Therefore, distributed power systems (DPSs) with buses of 48 V will be more feasible solutions for future high-end computers. This paper presents a novel multi-resonant push-pull (MRPP) topology for 48 V VRMs, based on methods for reducing the conduction loss and eliminating the body diode conduction and reverse-recovery losses of the synchronous rectifier. Two 48 V-1.2 V 70 A prototypes are built, and their efficiency is 86% at 1 MHz.