SEMICONDUCTOR MEMORY DEVICE

摘要

PROBLEM TO BE SOLVED: To average the number of times for eliminating respective blocks by exchanging data of the blocks based on the number of the eliminating times of the respective blocks. SOLUTION: A main control part compares and searches the counter areas 5 of the respective blocks in a flash memory 2, detects the blocks having the maximum number and the minimum number of eliminating times and sets them in variables E-MAX and E-MIN. When the value of the variable E-MAX is the integer-fold of a first prescribed value and a difference with the variable E-MIN is not less than a second prescribed value, the main control part copies all data in the blocks in the flash memory 2, which have the same block numbers as the value in the variable E-MAX, into RAM and all data in the maximum eliminating block are eliminated. Then, data except for eliminating time data in the minimum eliminating block is copied into the maximum eliminating block, all data in the minimum eliminating block are eliminated and data except for eliminating time data in the maximum eliminating block which is saved/ copied in RAM is written into the minimum eliminating block.