In modern data centers, the conversion of the 48-V bus to the CPU/GPU core voltage typically includes a two-step process. First, an unregulated intermediate bus converter generates an intermediate bus voltage, commonly around 12-V. Then, a high-bandwidth multiphase voltage regulation module (VRM) provides the regulated core voltage. A lower intermediate bus voltage offers several advantages such as relaxed VRM specifications or the on-chip implementation of integrated and fully integrated voltage regulators in CMOS technology. To achieve a lower intermediate bus voltage, hybrid resonant switched-capacitor converters (SCC) utilize a multi-tapped autotransformer (MTA) to improve the conversion ratio of switched-capacitor converters. This paper introduces a novel scalable hybrid resonant converter based on the Dickson SCC structure. A prototype designed for converting 48-V to 3.4-V has been implemented to validate the proposed topology. A peak efficiency of 96.6% and a maximum output current of 260-A are demonstrated. With a 48-V input voltage, the converter achieves a maximum power density of 920-W/inch3.
