A High Conversion Ratio Matrix Autotransformer Switched-Capacitor Converter for 48 V Datacenter Application

This article proposes a matrix autotransformer switched-capacitor dc–dc converter (MASC) that converts 48 to 3.2 V for datacenter applications. The proposed MASC is similar to the series capacitor buck with integrated inductors; however, it works at resonant mode to achieve zero voltage switching switching. The operating principle and the power losses of the proposed circuit including both of the autotransformer and semiconductor devices are analyzed. Compared with a switched-tank converter with the same conversion ratio, the power loss of semiconductor devices can be reduced by 68%. Furthermore, compared with an LLC converter with an isolated matrix transformer, the copper loss of the proposed matrix autotransformer can be reduced by 50%. Finally, a hardware prototype has been designed and developed, both simulation and experimental results have been provided to demonstrate the feasibility and validity of the proposed circuit.