A Single-Inductor Multi-Output (SIMO) Hybrid Buck Converter with Load-Dependent Sequencing Technique for Wide Output Voltage Range

This study presents a single-inductor multi-output dual-path hybrid buck converter by applying a load-dependent sequencing technique to obtain output voltages (VOUTs) over a wide range. When the conventional hybrid dual-path topology is applied to multi-output applications, the charging and discharging voltages of the inductor current are not properly formed as the various VOUT levels are applied to the inductor. The violation of the inductor volt-second rule is addressed using the proposed topology. Four VOUTs were regulated from 1.4 V to 3.3 V with an input voltage of 4.5 V. A dual-path current flows to the heaviest-load output regardless of the order of VOUTs connected to the inductor. With a 250-mΩ inductor, the maximum power conversion efficiency was measured as 90.13%.