Switch driver circuit for providing small sector sizes for negative gate erase flash EEPROMS using a standard twin-well CMOS process

摘要

For negative gate erase and programming of non-volatile floating gate EEPROM devices, large positive or negative voltages from one single negative charge pump and from one single positive charge pump are selectively switched onto a one or more memory sectors of twin-well CMOS negative-gate-erase memory cells. The control gate is negative during erasing and positive during programming. In order for FLASH memories to have minimum layout area, small sectors or arrays of EEPROM cells can be erased all at once using a charge pump which includes two pump capacitors to provide negative voltages to the gate terminals of one or more series PMOS transistors.