| 摘要 |
PROBLEM TO BE SOLVED: To achieve erasure lock in page units. SOLUTION: In a rewritable non-volatile memory device which can be programmed by erasing a memory transistor in page units, a lock cell 11 which can be erased and programmed being provided for each word line and control means 13 and 16 for setting a lock cell to a first state by providing a program prevention voltage to the bit line of the lock cell with a program when setting the erasure lock and for setting the lock cell to a second state by providing a grounding voltage to the bit line of the lock cell with a program when no erasure lock is set are provided. Then, when the lock cell is in the first state, the erasure and programming of the memory transistor connected to the word line of the lock cell can be inhibited. Also, when the lock cell is in the second state, the erasure and programming of the memory transistor connected to the word line of the lock cell are allowed.
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