Patent ID: 7928962

Claim:
An optical pointing device comprising: an optical unit that irradiates light to an object using a light source and receives light reflected by the object to output an optical image; a motion sensor that receives the optical image, senses image data, and calculates a motion value to output the motion value; a moving velocity sensor that receives the motion value and calculates a moving velocity of the optical pointing device to output the moving velocity; and a variable power supply that generates a different power supply voltage according to the moving velocity, wherein the variable power supply comprises at least one power supply voltage drop portion and at least one power supply voltage boost portion, wherein the power supply voltage drop portion comprises: a voltage-drop regulator that receives a power supply voltage to output a dropped power supply voltage; a first reference voltage generator that receives the power supply voltage to generate a first reference voltage, a first voltage division controller that outputs first and second drop voltage division control signals according to the moving velocity; a first voltage divider that outputs a first varied division voltage in response to the first and second voltage division control signals; a first comparator that receives the first varied division voltage and the first reference voltage and compares the level of the first varied division voltage with the level of the first reference voltage to output a first comparison output signal; and a first switch controller that controls the voltage-drop regulator to vary the dropped power supply voltage in response to the first comparison output signal, and wherein the power supply voltage boost portion comprises: a voltage-boost regulator that receives the power supply voltage to output a boosted power supply voltage; a second reference voltage generator that receives the power supply voltage to generate a second reference voltage; a second voltage division controller that outputs first and second boost voltage division control signals according to the moving velocity; a second voltage divider that outputs a second varied division voltage in response to the first and second boost voltage division control signals; a second comparator that receives the second varied division voltage and the second reference voltage and compares the level of the second varied division voltage with the level of the second reference voltage to output a second comparison output signal; and a second switch controller that controls the voltage-boost regulator to vary the boosted power supply voltage in response to the second comparison output signal.