| 摘要 |
PURPOSE:To prevent power interruption while preventing the capacity of backup power supply from lowering. CONSTITUTION:First power supply V1 in a backup power supply V has a voltage lower than the voltage at an input terminal 101,and continuously connected through a diode D3 with an output terminal 102 so that the power can be fed immediately upon power interruption. On the other hand, a second power supply V2 is connected through a diode D2 with the output terminal when a switch S1 detects an abnormal voltage at the input terminal 101. Consequently, power is not interrupted at the output terminal 102 and incessant drain of current from the backup power supply V can also be prevented. |
