Electrically alterable non-volatile memory with N-bits per cell

摘要

An electrically alterable, non-volatile multi-bit memory cell has Kn predetermined memory states (Kn>2), where K is a base of a predetermined number system and n is a number of bits stored per cell. Programming of the cell is verified by selecting a reference signal corresponding to the information to be stored and comparing a signal of the cell with the selected reference signal.