Multiple logic levels can be simultaneously programmed into any combination of memory cells in a column of an alternate-metal virtual-ground (AMG) EPROM or flash memory array by applying one of a corresponding number of programming voltages to the word lines that correspond with the cells to be programmed....http://www.google.es/patents/US5557567?utm_source=gb-gplus-sharePatente US5557567 - Method for programming an AMG EPROM or flash memory when cells of the array are formed to store multiple bits of data
Method for programming an AMG EPROM or flash memory when cells of the array ...
