Portable electronic unit restoring mains supply after operation on temporary source following power cut, employs clock and processor to manage switch timing

摘要

A power detection module (130) signals (132) when the main power source (150) output falls below a threshold. The processor (140) responds by sending out switching signals. A clock (110) responds to an ON signal by timing a notification interval, the clock being supplied directly by a reserve power source (160). The energy manager (120) is connected to both sources. It disconnects the main energy source from a circuit block with high energy consumption when the OFF signal is given. It re-connects them when the notification signal is given, and the main supply output is above a second threshold.