| 摘要 |
<p>PROBLEM TO BE SOLVED: To suppress the consumption of a backup power source as much as possible even when a main power source is disconnected during system operation. SOLUTION: This system is equipped with a microcomputer 21 which is powered by the main power source 1 in normal operation mode to control the system 6 and powered by a backup battery 9 switched from the main power source 1 in sleep mode to operate and a voltage detecting circuit 5 which monitors whether or not the power supply from the main power source 1 to the microcomputer 21 being cut off. If the main power source 1 is disconnected during the system operation, the voltage detecting circuit 5 outputs power-source monitor data D1 of 'L' level as an interruption request to the microcomputer 21.</p> |
