An Isolated Single-Stage Voltage Regulator With High Step-Down Conversion Ratio for Data Center Application

As data center power architectures evolve from 12 V to 48 V to accommodate escalating power densities, designing high-efficiency, high-step-down voltage regulators (VRMs) with high current capability becomes a critical challenge. Existing solutions, such as hybrid switched-capacitor converters, offer high power density but often entail complex driving schemes and high component counts. To address these limitations, this paper proposes a scalable "DC Panama" single-stage converter tailored for vertical power supply. Inspired by the series-input and parallel-output configuration of the grid-side Panama architecture, the proposed topology naturally achieves voltage balancing and high current sharing without extreme duty cycles. A key finding of this research is the optimization of a four-phase coupled inductor, which effectively decouples the steady-state equivalent inductance from the transient equivalent inductance. This achievement mitigates the inherent conflict between low output ripple and fast dynamic response found in conventional designs. A 100 A prototype operating at 300 kHz is built to validate the theoretical analysis. The experimental results demonstrate a peak efficiency of 86.2% and robust operation under heavy load conditions, proving the proposed architecture is a competitive solution for next-generation high-current data center power supplies.