A Single-Inductor Multiple-Output Auto-Buck–Boost DC–DC Converter With Tail-Current Control

Abstract

A single-inductor multiple-output (SIMO) auto-buck-boost dc-dc converter with proposed tail-current control to achieve fast and robust reference tracking of inductor current is proposed in this paper. Moreover, the proposed backward-V <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">x1</sub> control algorithm and frequency-control loop enable the proposed SIMO dc-dc converter to operate at a fixed switching frequency and achieve high power-conversion efficiency in both the buckdominated and boost-dominated cases. The proposed SIMO auto-buck-boost dc-dc converter has four output channels and is implemented in a standard 0.35-μm CMOS process. Measurement results show that the proposed dc-dc converter achieves a peak efficiency of more than 91% at a total output power of about 0.5 W and load transient response time of less than 80 μs.