| 摘要 |
PROBLEM TO BE SOLVED: To provide a memory system having longer life or higher reliability of the whole system as compared with conventional practice by taking account of a variance in consistency of write and erase frequency between lot, individual, chip, block, etc.SOLUTION: The memory system includes: a nonvolatile semiconductor memory 10 having a plurality of normal blocks 1-n which are units of data erase, and a dummy block D; a write control part 13 for rewriting not less than maximum rewriting frequency of the plurality of normal blocks 1-n to the dummy block D; a monitor part 11 for monitoring a data erase period or write period of the dummy block D; and a wear leveling control part 12 for averaging the rewriting frequency between the normal blocks 1-n, wherein decision is made whether the rewriting of the normal blocks 1-n can be continued or not, based on the monitoring result of the monitor part 11. |
