| 摘要 |
<p>PROBLEM TO BE SOLVED: To improve the reliability in data having been read by enabling a data error to be corrected reliably, even if a threshold control method and data retention characteristics have some problems in a multiple-value memory and a data access method thereto. SOLUTION: An analog quantity that can be classified into a plurality of levels according to a size can be retained, and a plurality of memory cells that can store at least three logical values according to the level of the analog quantity to be retained are provided. Then, the analog quantity that the memory cell retains and the logic value that the memory cell stores are related so that a hamming distance between two logic values corresponding to (i)th-level analog quantity and (i) + first level analog quantity becomes 1.</p> |
