A Paired MOS Charge Pump for Low Voltage Operation

We present a new multi-stage charge pump that is suitable for low-voltage operation, and in particular for low voltage flash memory. Compare to the Dickson charge pump and previously reported modified Dickson charge pumps, the proposed charge pump offers the improved pumping voltage gains. The proposed charge pump is composed of a pair of pumps and utilizes the internal boosted voltages of one side of the paired pumps as the charge transferring voltages to the other side. The simulated and measured results indicate that the proposed pump is highly efficient in overcoming both the pumping gain decrease and the current driving capability degradation caused by the threshold voltage of the charge-transfer gate.