A Pseudo-LDO-Assist Charge-Control SIMO Buck DC-DC with 0.02 mV/mA Cross Regulation

Abstract

Cross-regulation (CR) suppression is a challenge in single-inductor-multiple-output (SIMO) DC-DC. The pseudo-LDO-assist technology is presented to decrease CR of charge-control SIMO Buck DC-DC in this paper. With the fast current compensation of the proposed pseudo-LDO, the CR of the last DC-output, which used to be the largest CR in traditional charge-control SIMO, could be suppressed to the same level as that of the other DC-outputs regulated by charge control. Experimental results show that the largest CR of the proposed SIMO Buck DC-DC is 0.02 mV/mA in 488 mA load transient, which shows a 42.86% improvement compared to the existing charge-control SIMO.