| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide an EEPROM of a multi-valued storage system which can simplify a control circuit other than a memory cell. SOLUTION: This device is provided with a data storage circuit 9 storing control data deciding writing control voltage applied to each bit line BL in an EEPROM of a multi-value storage system during writing operation, writing control voltage is applied to a corresponding bit line respectively based on control data stored in the data storage circuit 9 at the time of writing, a read- out bit line signal is applied selectively to corresponding bit lines respectively based on control data stored in the data storage circuit 9 at the time of read- out. And a value of a read-out bit line signal on a corresponding bit line modulated by a writing state of a memory cell is detected at the time of write-in verifying, and control data stored in the data storage circuit 9 is changed in accordance with a writing state of a memory cell.</p> |
