Patent ID: 7120403

Claim:
A power saving auto-off circuit for a wireless transmitter for an audio source, said auto-off circuit comprising: a field effect transistor (FET) adapted to pinch off charge carriers when said auto-off circuit is in an “off” state; a capacitor connected to said FET and adapted to be charged and discharged, and if not discharged will charge to a pre-determined threshold causing said FET to pinch off; a comparator connected to said capacitor and having an open drain output and an input, said input adapted to be dropped in value below a pre-determined threshold limit when presented with an audio peak, and wherein said drop in value causes said capacitor to discharge; regulator means for producing an output when supplied with power, said regulator means connected to said comparator and enabling said comparator output to discharge said capacitor; and switch means connected to said capacitor and adapted to discharge said capacitor when activated to cause said FET to supply power to said regulator.