NONVOLATILE STORAGE DEVICE

• Main Authors: SONOYAMA HIROSHI, MIYATA SHUSAKU, IZAWA KAZUTO, FURUSAWA KAZUNORI
• Format: Patent
• Language: English
• Published: 04.10.2007
• Subjects: INFORMATION STORAGE; PHYSICS; STATIC STORES

PROBLEM TO BE SOLVED: To provide a nonvolatile storage device which can reduce an apparent variation in threshold voltage due to capacitive coupling among nonvolatile memory cells. SOLUTION: The nonvolatile storage device is provided with a memory array, a data buffer and a control circuit. The memory array is provided with a plurality of sections (SECs) which have a plurality of erasing and writing units (BLKs) that respectively have a plurality of electrically erasable and writable nonvolatile memory cells. In response to a rewrite instruction for storage information, the erasing and writing order for the erasing and writing units in the storage section to be rewriten is controlled in one direction to the arrangement order of the erasing and writing units. Thus, an influence of capacitive coupling on the variation of threshold voltage can be limited to only influence from adjacent one direction. Since a previous unit adjacent to the unit in one direction is erased first, the influence from the adjacent one direction can be limited only for writing. COPYRIGHT: (C)2008,JPO&INPIT