A Dickson-Squared Hybrid Switched-Capacitor Converter for Direct 48 V to Point-of-Load Conversion

Abstract

More energy-efficient and power-dense solutions to 48 V to point-of-load (PoL) power conversion are required for modern and future data center power delivery. This paper proposes a Dickson-squared hybrid switched-capacitor (SC) con-verter for direct 48 V-to-PoL conversion with high efficiency and high power density. The proposed topology comprises a 9-to-1 SC stage that can be viewed as two 3-to-1 Dickson SC converters combined together and a nine-phase interleaved buck stage. The proposed topology can achieve complete soft-charging operation with a simple control, ensure naturally balanced interleaved inductor currents, enable reduced conversion burden on the buck stage, and eliminate the need for large bus capacitors with a switching bus architecture. A 48 V-to-PoL hardware prototype is built to verify the performance of the proposed converter, achieving 93.8% peak efficiency and 360 W/in3power density at 1.0 V output voltage.