Memory failure diagnosis device and memory failure diagnosis method

摘要

An area of a memory has a diagnosis area and a non diagnosis area, with the diagnosis area divided into a plurality of Row areas which do not overlap each other, and each of the Row areas is divided into a plurality of Cell areas which do not overlap each other. A memory fault diagnostic method has a diagnostic step in a Row area to diagnose between Cell areas with respect to all the combinations of a set of Cell areas in the Row area, and a diagnostic step between Row areas to diagnose between Row areas with respect to all the combinations of a set of Row areas in the diagnosis area. A Row area size is determined to be a size in which a time of the diagnosis in a Row area becomes equal to a time of the diagnosis between Row areas.