A multi-mode low ripple charge pump with active regulation

Abstract

In order to improve efficiency and reduce the output ripple, a novel multi-mode charge pump is presented. The proposed charge pump includes dual-loop regulation topology-skip and linear modes. It consumes low quiescent current in skip mode for light loads, and produces low ripple in linear mode for heavy loads, which closes the gap between linear mode and skip mode with active regulation; a multi-mode charge pump employing the technique has been implemented in the UMC 0.6-μm-BCD process. The results indicate that the charge pump works well and effectively; it has low ripple with special regulation, and minimizes the size of the capacitance, then decreases the area of the PCB board. The adjustable output of the positive charge pump is 10–30 V, and the maximum output ripple is 100 mV when the load current is 200 mA. The line regulation is 0.2%/V, and load regulation is 0.075%.