Single-Inductor Dual-Output DC-DC Converter with Multiple Flying Capacitors

Abstract

This paper presents a novel single-inductor dual-output (SIDO) DC-DC converter topology with two flying capacitors. The two flying capacitors are located in the same current path, targeting an enhanced voltage drop reduction on the inductor, and a decrease in the inductor current slope, aiming for improved power efficiency and relaxed coil current constraints. Using specifications addressing battery-powered display driver applications, simulation results show up to 7.7% efficiency improvement compared to the conventional SIDO converter and up to 4.9% efficiency improvement compared to the SIDO converter with one flying capacitor topology. In addition, a reduction in inductor peak current and ripple can be achieved, along with a lower duty cycle operation, which all lead to relaxed coil selection criteria and relaxed converter stability constraints.