Patent ID: 8068073
Filing Date: 2011-11-29
Classification: G09G

Abstract:
1. A pixel driving circuit for an organic electroluminescent display comprising: an organic electroluminescent device that emits light corresponding to an amount of a current being applied; a first transistor connected to a power supply voltage for applying the current corresponding to a data voltage to the organic electroluminescent device; a first capacitor connected between a gate electrode of the first transistor and the power supply voltage for charging the data voltage; a threshold voltage compensation unit for charging a voltage corresponding to a threshold voltage of the first transistor in response to a selection signal from an (n−1)th scan line; a second transistor for transmitting the data voltage from a data line in response to a selection signal from an nth scan line; and a switching unit for electrically disconnecting the first transistor from the organic electroluminescent device while the voltage corresponding to the threshold voltage is being charged in the threshold voltage compensation unit in response to a control signal, wherein the threshold voltage compensation unit includes a third transistor for configuring the first transistor as a diode in response to the selection signal from the (n−1)th scan line.