Novel architecture for virtual ground high-density EPROMS

摘要

A virtual ground electrically programmable read-only memory device in which disturbance to neighboring cells is practically eliminated, is disclosed. In one embodiment the memory device comprises a plurality of memory cells formed in a semiconductor substrate and arranged in rows and columns so as to form an array. During read operations, pairs of adjacent cells are accessed simultaneously by grounding a single column line within the array. The two adjacent column lines-one on each side of the grounded column line-are coupled to separate read paths. Within the array, rows of cells store bits from a plurality of data bytes according to a pattern in which pairs of adjacent cells store different bits from different bytes.