Patent ID: 8564579
Filing Date: 2013-10-22
Classification: G01J,G02F,G09G,H04N,H05B

Abstract:
1. An ambient light sensing circuit, comprising: a photodiode that flows a current in proportion to ambient light; a first storage capacitor that is electrically coupled with the photodiode and is discharged after being charged with a voltage of a first power supply; a second storage capacitor that is electrically coupled with the first storage capacitor and provides a coupling voltage; and a transistor that outputs a current from the first power supply corresponding to the coupling voltage of the first storage capacitor and the second storage capacitor after being electrically coupled with the second storage capacitor, wherein a first electrode of the transistor is electrically coupled with a third switch that supplies the first power supply, the first electrode of the transistor being different from a control electrode of the transistor, a fourth switch is electrically coupled between a second electrode and the control electrode of the transistor, the second electrode of the transistor is electrically coupled with a fifth switch that supplies a second power supply, and an output terminal for outputting a current, the output terminal being between the first electrode of the transistor and the third switch.