| 摘要 |
<p>PROBLEM TO BE SOLVED: To prevent a malfunction of a microcomputer associated with the drop of power supply voltage. SOLUTION: Total impedance of plural MOS transistors 5 and 6 which constitutes at least one bit of a specific address of a mask ROM is set to be appropriate value that is larger than total impedance of plural MOS transistors 5 and 6 which constitutes each bit of the other addresses of the mask ROM. With this, the effective range of power supply voltage of the microcomputer can be secured widely and the reset of the microcomputer or an alarm of battery exchange, etc., is surely carried out at a stage before the microcomputer malfunctions.</p> |
