Design of Negative Charge Pump for Flash Memory

This paper proposes a method for the implementation of a negative voltage charge pump in Flash memories, which is suitable for use with single power supply and low voltage power supply.Based on the principles of the operations of charge pumps and taking into consideration the various requirements of NOR flash memories for negative voltage, we propose a negative charge pump circuit structure which effectively inhibits program disturb.The paper concludes with circuit simulations at different PVT corners which indicate that the charge pump outputs voltage at-300 mV within 2μs upon system power up, satisfying design requirements.