| 摘要 |
PROBLEM TO BE SOLVED: To improve reliability of a semiconductor memory device after product shipment thereof.SOLUTION: A semiconductor memory device 1 includes: a nonvolatile semiconductor memory 3; a power supply section 5; and a controller 2. When a voltage is supplied to the controller 2 from the power supply section 5, the controller 2 reads out firmware from the nonvolatile semiconductor memory 3 and executes a normal mode or a free-running mode. When the firmware is the free-running mode, the controller 2 performs writing in a user area with a cell application voltage higher than a voltage of the normal mode and, subsequently, repeats erasing, writing and reading out with the voltage of the normal mode for each block in the user area. When an erasure error occurs at the time of the erasing or a writing error occurs at the time of the writing, the controller 2 adds a block where the erasure error occurs or the writing error occurs to a bad block management table. |
