The circuit topology construction method of a series-capacitor-transformer hybrid high step-down ratio Buck converter is proposed. By further introducing a transformer/coupled inductor into the traditional series-capacitor Buck circuit

the step-down ratio of the converter is significantly improved

while the inherent inter-phase current sharing capability of the series-capacitor Buck converter is retained. This paper elaborates on the construction process of the hybrid Buck converter in detail

and analyzes the working principle and characteristics of the converter. For the two-phase hybrid Buck converter

a planar magnetic integration structure of dual transformers/coupled inductors is designed based on the magnetic flux cancellation principle. Accordingly

an experimental prototype with 27~40 V input and 1.8 V/100 A output is developed and tested. Experimental results verify the feasibility and effectiveness of the proposed hybrid Buck converter.