COMPEL 2020: Two-Stage 48V-1V Hybrid Switched-Capacitor PoL Converter with 24V Intermediate Bus

Conference: COMPEL 2020
Presenter: Yenan Chen
Abstract: This paper presents a 90.6% 48 V-1 V/150 A two-stage hybrid switched-capacitor point-of-load (PoL) converter with a 24 V intermediate bus. The first stage of the converter is a 2:1 resonant charge pump which converts the 48 V input voltage to 24 V. The second stage of the converter is a 24:1 four-phase series capacitor buck converter which is capable of delivering 150 A with two customized four-phase coupled inductor for vertical power delivery. The two-stage architecture combines the resonant switched-capacitor structure and the series capacitor buck configuration to achieve high efficiency, high power density, and voltage regulation. The effectiveness of the topology is verified by a 48 V-1 V/150 A prototype with a peak efficiency of 90.6% at 60 A and a full load efficiency of 86.2% at 150 A. The power density of the prototype is 283 W/in^3.