A Hybrid-Type High Step-Down DC/DC Converter Using a Step-Down Cross-Connected Fibonacci Converter

For 48V data center applications, we present a new hybrid-type high step-down dc/dc converter with single inductor. Unlike conventional high step-down switched capacitor converters, the proposed converter is designed by connecting a step-down cross-connected Fibonacci converter to a traditional buck converter in series, where the cross-connected Fibonacci converter which is designed by switched capacitor techniques achieves high step-down gain without cascade connection of switched capacitor converter cells. Furthermore, series-connected topology with single-inductor enables high voltage gain, small size, and light weight. The given theoretical analysis and the performed simulations demonstrated that the power efficiency of the proposed high step-down converter is higher than that of the conventional high step-down converters. Concretely, the proposed converter can achieve 91%@2W and 76%@2W in the case of 1/19× and 1/53× voltage gains, respectively. Furthermore, the done breadboard experiments validated the feasibility of the proposed topology.