Patent ID: 7127228

Claim:
A portable electronic device with power failure recovery, powered by a main power source, comprising: a power detection module, detecting an output characteristic from the main power source, for asserting an interrupt signal if the detected output characteristic is below a first threshold value; a processor, responsive to the interrupt signal, for asserting a turn-off signal and an enable signal; a timing unit, responsive to the enable signal, for asserting a notification signal at a predetermined time interval when the enable signal is asserted, wherein the timing unit is directly powered by a backup power source; and a power management unit, electrically coupled to the main power source and the backup power source, for disconnecting the main power source from a circuit block when the turn-off signal is asserted, and for reconnecting the main power source to the circuit block when the notification signal is asserted and the output characteristic of the main power source is beyond a second threshold value.