A robust cross-regulation-suppressed single-inductor multiple-output dc-dc converter with duty-regulated comparator control

Abstract

A robust cross-regulation-suppressed single-inductor multiple-output (SIMO) dc-dc converter with duty-regulated comparator control is proposed. The control scheme effectively combines comparator-based and linear-compensator-based controllers to achieve fast load-transient response and low cross regulation to other output channels simultaneously. The control algorithm does not rely on duty-inductor-current feed-forward which is sensitive to the accuracy of inductor-current sensor. As a result, it can provide robust cross-regulation suppression for a wide range of loading for the SIMO dc-dc converter. Moreover, together with the average-inductor-current control, the proposed control algorithm is suitable for SIMO dc-dc converter which has auto-buck-boost property for each sub-converter, which makes the SIMO converter suitable for dynamic voltage scaling applications.