Patent ID: 6529067
Filing Date: 2003-03-04
Classification: G06F,Y02D

Abstract:
A power saving device mounted in a wireless pointer that includes a pointer signal generation circuit powered by a power source, said power saving device comprising:a first capacitor and semiconductor means for supplying a leakage current to charge said capacitor, said first capacitor and said semiconductor means being connected in series with said power source; a switch connected between ground and a first node between said first capacitor and said semiconductor means such that said capacitor discharges when said switch is closed; an n-type channel MOSFET having a gate connected to said first node; and a first resistor and second capacitor connected in series with said power source, wherein a drain of said MOSFET is connected to a second node between said first resistor and said second capacitor, said second node being connected to said pointer signal generation circuit, wherein a gate conduction voltage of said MOSFET is less than a voltage at said first node when said capacitor is fully charged by said leakage current such that when said switch is open and said capacitor is fully charged, said MOSFET conducts to place said pointer signal generation circuit in a stand-by state in which current is drawn through said first resistor, and such that when said switch is closed and said first capacitor discharges through said switch, said MOSFET is rendered non-conductive to enable driving of said pointer signal generation circuit.