Isolated resonant full-bridge converter with magnetic integration

Abstract

Nowadays technological developments in modern microprocessors have brought better computing performance and have triggered the demand for high-efficiency power supply. The common trend in networking applications is to have a 48V dc distribution bus to increase system efficiency, while the supply of the microprocessor is usually obtained by a two-stage conversion process having an intermediate 12V dc bus. This paper presents a single-stage approach for the isolated voltage regulation module (VRM) based on a resonant topology that inherently integrates the multi-phase approach. In order to fit the layout constraints of the processor mother board, this paper also presents some magnetic architectures which integrate the magnetic parts. Compared to a classical discrete implementation, the proposed integrated magnetic structures have smaller total volume. In this paper we will compare the magnetic structures in the same application that is a processor power supply conversion from 48V bus. The proposed integrated magnetic architectures can be applied to other topologies as conventional ZVS full bridge. Experimental results on a 250A, 1.8 V multiphase isolated conversion are provided to show the effectiveness of the proposed solutions.