Patent ID: 7211907

Claim:
A programmable power control unit for connecting a device to a battery to supply power from the battery to the device, the unit comprising: a first contact to connect to the battery; a second contact to connect to the device; a relay disposed between the first contact and the second contact to electrically connect the first contact to the second contact in response to a signal; a voltage detector connected to the first contact to detect a voltage at the first contact; and a processor to generate the signal to engage the relay if the voltage detected by the detector is above a predetermined level V 1 , to implement a timer function to count down a time period T 1 when the detected voltage falls below V 1 and the relay is engaged, to reset the timer if the detected voltage rises above V 1 during a countdown, and to remove the signal to disengage the relay when the timer times out, and to remove the engage signal to disengage the relay if the detected voltage falls below a second predetermined voltage V 2 , wherein V 2 <V 1 .