Always-Dual-Path Hybrid DC-DC Converter Achieving High Efficiency at Around 2:1 Step-Down Ratio

An always-dual-path hybrid (ADPH) DC-DC converter using one inductor and two flying capacitors with the step-down ratio from 3:1 to 1:1 is proposed to achieve high efficiency at the commonly used 2:1 step-down ratio by reducing the inductor current. The proposed ADPH converter is designed for a 24 V-to-13 V bus converter for truck auxiliary equipment. In the measurement, the peak efficiency of the proposed 24 V-to-13 V converter is 97.4 % at 146 W, and the inductor conduction loss is reduced by 67.2 % by reducing the inductor DC current by 42.7 %.