A 1.2-μA SIMO DC-DC Converter with 0.04-mV/mA Cross Regulation under Simultaneous Multi-Channel Loading Transition

This article presents a low-power single-inductor multioutput (SIMO) DC-DC converter with three independent outputs. An asynchronous balanced power-distributive control (BPDC) is proposed to reduce the delay charging period of the channels to mitigate the cross regulation. Implemented in a $0.18-\mu \mathrm{m}$ BCD technology, the proposed SIMO converter achieves a quiescent current of $1.2 \mu \mathrm{A}$ and a peak efficiency of 91.8%. A power efficiency of 83.9% is measured under $10-\mu \mathrm{A}$ loading current. The measured transient response time is $1.7 \mu \mathrm{s}$ with $0.38-\mathrm{mV} / \mathrm{mA}$ output voltage droop when loading changes from $10 \mu \mathrm{A}$ to 100 mA. Moreover, the cross regulation has minimized to be $0.04 \mathrm{mV} / \mathrm{mA}$ when the load currents of other 2 channels change simultaneously.