A 60-ns 16-Mb flash EEPROM with program and erase sequence controller

An erase and program control system has been implemented in a 60-ns 16-Mb flash EEPROM. The memory array is divided into 64 blocks, in each block, erase pulse application and erase-verify operation are employed individually. The erase and program sequence is controlled by an internal sequence controller composed of a synchronous circuit with an on-chip oscillator. A 60-ns access time has been achieved with a differential sensing scheme utilizing dummy cells. A cell size of 1.8 mu m*2.0 mu m and a chip size of 6.5 mm*18.4 mm were achieved using a simple stacked gate cell structure and 0.6- mu m CMOS process.>