Abstract: A hybrid-type bus-converter and high-density integration for data-center 48 V power supply systems is proposed. By embedding autotransformer and LLC resonant converter into the switched capacitor converter, the step-down ratio of the switched capacitor converter is greatly increased, and the output current capability of the converter is significantly improved by using the matrix transformer structure. Based on the proposed hybrid-type bus-converter, a high-density integration method is further proposed, which comprehensively adopts magnetic integration and winding integration to improve the power density and efficiency of the converter. A one-eighth brick module with 40~60 V input, 8 : 1 transformation ratio, 100 A output current and 1 MHz switching frequency has been developed. The power density reaches 1.704 kW/in³ and the highest efficiency reaches 97.9%.