Memory correction scheme using spare arrays

摘要

Spare chips are employed together with a replacement algorithm to replace chips in memory array when failure is generally more extensive then unrelated cell fails in the memory chips. That is, substitution will be made if an error condition is a result of the failure of a whole chip (chip-kill), a segment of a chip (island-kill), a column of bits of a chip or a row of bits of a chip but will not be performed when it is due to a single failed cell. The replacement of a chip with a chip-kill or with an island-kill is done on the fly and involves only a row of the memory chips or elements leaving other elements of the memory unaffected by the replacement.