| 摘要 |
PROBLEM TO BE SOLVED: To avoid the erroneous writing control of the nonvolatile memory unit of a control processing unit when the voltage of a driving power supply rises. SOLUTION: A power supply state detection unit 13 which compares the voltage of the driving power supply of a control processing unit 4 with a predetermined threshold voltage, and outputs a power supply unstability detection signal until the voltage of the driving power supply exceeds the threshold voltage; and a writing prohibiting gate unit 17 which clamps a control terminal related to the writing of a memory unit 10 at a control prohibiting level to prohibit the writing in the memory unit 10, while the power supply unstability detection signal is outputted; are provided. |
