Patent ID: 8159423

Claim:
An organic light emitting display device, comprising: a scan driver configured to drive scan lines, first control lines, and light emission control lines; a data driver configured to supply initialization voltages to data lines during a first subperiod of a horizontal period and configured to supply data signals to the data lines during a second subperiod of the horizontal period; and pixels positioned at crossing areas of the scan lines and the data lines, each of the pixels comprising: an organic light emitting diode; a pixel circuit comprising a first transistor for controlling an amount of current flowing from a first power supply through the organic light emitting diode to a second power supply, the first transistor configured to receive the initialization voltage at its gate electrode during the first subperiod; and a compensation unit coupled between the gate electrode and a source electrode of the first transistor, the compensation unit configured to control voltage at the gate electrode of the first transistor corresponding to a deterioration of the organic light emitting diode, the compensation unit comprising a second transistor and a first capacitor serially coupled between the gate electrode and the source electrode of the first transistor.