A low-voltage charge pump with wide current driving capability

Abstract

A high current driving capability charge pump circuit is proposed. By adopting the dynamic boosting circuit, the overdrive voltages of all the charge transfer switches (CTS's) in the charge pump are maintained for a large loading current. In addition, the largest voltage difference between any of the terminals of all the transistors does not exceed the supply voltage VDD, and solves the gate-oxide overstress problem in the conventional charge pump circuits and enhances the reliability. Other advantages of the proposed charge pump include high pumping efficiency because of no threshold voltage drop and 2-phase operation, without the need of extra power consumption on the logic circuits and drivers. The proposed charge pump circuit is designed and simulated based on a low voltage process. Results show that the charge pump can operate in a wide output current range.