A 1.2 mV ripple, 4.5 V charge pump using controllable pumping current technology

Abstract

This paper represents a 4.5 V regulated charge pump with extremely small ripple. The pump designed with Voltage Doubler (VD) significantly reduces the output ripple voltage. In addition, this circuit utilizes a controllable pumping current (CPC) technology, which achieves automatically adjusting output current by feedback mechanism and resizing transfer transistors. The proposed charge pump has been demonstrated in 0.32 µm 3D NAND periphery technology under 3 V power supply. Simulation results show that the output ripple voltage is 1.2 mV at 5 mA load current with 0.1 µF load capacitance. The maximum current drivability and power efficiency is 8 mA and 81% respectively.