Hybrid-Switched-Capacitor Voltage Regulator Module with Multifunctional Components

This paper presents a family of quasi-two-stage hybrid-switched-capacitor (HSC) voltage regulator module (VRM) with multifunctional components for both 12-V-to-1-V and 48-V-to-1-V high-current applications. A switched-capacitor stage splits the input voltage into multiple square-wave voltage rails. A PWM regulator stage with multiple cells are driven by the square-wave voltage rails. The flying capacitors of the switched-capacitor stage are reused as the input filter of the PWM regulator stage. The filter inductors of the PWM regulator stage are reused to softly charge/discharge the flying capacitors. A terminal switch of the switched-capacitor stage and a high-side switch of the PWM regulator stage are combined and replaced by a single switch. With multifuctional capacitors, inductors and switches, the component count and the on-resistance of the overall current path are reduced and the efficiency of powering high-current microprocessors can be proved. The operation principle and parameter design of the HSC-VRM are introduced. A 12-V-to-1-V/160-A/1-MHz prototype with a 92.1% peak efficiency and a 85.6% full-load efficiency is built to verified the effectiveness of the topology family.