A 96.1% Efficiency Single-Inductor Multiple-Output (SIMO) Buck Converter With 2.1-A/ns Transient Speed and 2.2-A Maximum Current Capacity

Abstract

To overcome the limitations of transient handling capability, current capacity, power efficiency, and current density in existing single-inductor multiple-output (SIMO) converters, this article presents: 1) loop response enhancement by the fully comparator-based “Buffet-Like” dual-sampling non-linear control; 2) voltage droop suppression by the hybrid digital LDO (HLDO) attached to each output; 3) efficiency enhancement by frequency hopping and bootstrapped N-type MOSFET (NMOS) output switches; and 4) the power density enhancement with a smaller than the chip power inductor. The prototype with two outputs achieves a transient handling capability of 2.1 A/ns, which is a significant advancement over the state of the art. A maximum current capacity of 2.2 A, and a peak efficiency of 96.1% are also measured using a 0806 miniature power inductor.