Patent ID: 7880692
Filing Date: 2011-02-01
Classification: G09G

Abstract:
1. A driver circuit of an AMOLED with gamma correction, comprising: a voltage selector selecting one of a plurality of gamma voltages; an operational amplifier receiving the selected gamma voltage and a feedback signal to generate a control signal; a MOS transistor providing the feedback signal and conducting a current associated with a current type pixel circuit in response to the control signal; and a resistive element coupled to a first voltage end and an inverted input end of the operational amplifier for determining the current with the selected gamma voltage, wherein the resistive element comprises: a first switch controlled by a clock signal; a capacitor connected to the first switch in parallel, and one end of the capacitor connected to the first voltage end; a second switch connected between the other end of the capacitor and the inverted input end of the operational amplifier, and controlled by an inverse clock signal; wherein the second switch is both an input and an output of the resistive element; and wherein there is no output capacitor associated with said output.