SENSOR CIRCUIT AND DRIVING CIRCUIT FOR LCD BACKLIGHT AND DRIVING METHOD THEREOF

摘要

A sensor circuit and a driving circuit for an LCD backlight and a driving method thereof are provided to perform a brightness control according to the luminance by excluding interference by the noise element. A photosensor circuit part(100) outputs the first signal voltage according to the incoming light amount. A temperature sensor circuit part(200) outputs the second signal voltage according to temperature. A comparison circuit unit(300) outputs the third signal voltage corresponding to the difference of the second signal voltage and the first signal voltage. A first switch which is switch-controlled with the first clock signal while the first voltage being input. A photosensor switching unit includes the second switch which is switch-controlled with the second clock signal while the second voltage being input and outputs the first signal voltage. A first storage capacitor charges the first voltage. A photo-sensor portion includes the photosensor formed the second voltage inputted with the second switch the voltage charged according to the incoming light amount in the first storage capacitor is discharged.