| 摘要 |
PURPOSE:To eliminate system down upon recovery of power, by arranging level detectors for detecting voltage drop at pre-stage and post-stage of a switch and controlling the switch based on detection of voltage drop. CONSTITUTION:AC input is provided through a first switch 1 to a charger section 2 so as to recharge a battery 3, and DC power is fed through a second switch 4 to a load 5. First and second rectifying level detectors 6, 7 for detecting droppage of rectified AC voltage are arranged at pre-stage and post-stage of the first switch 1. Detection of droppage of level through the first rectifying level detector 6 is judged to be power interruption, and detection of droppage of level only through the second rectifying level detector 7 is judged to be turned OFF of power source through the first switch 1. Upon power interruption, DC power is fed from the battery 3 through the second switch 4 to load 5. |
