| 摘要 |
An OLED display device and a driving method thereof are provided to enhance the reliability of image quality by preventing the variation of driving currents of an OLED element due to the variation of characteristics of a driving TFT(Thin Film Transistor). An OLED(Organic Light Emitting Diode) display device includes data and gate lines, a high level driving voltage source(VDD), a source-follower circuit(122-1), an OLED element(OLED), an offset capacitor(Cos), and a switch circuit(122-2). The data lines receive data voltages. The gate lines crossing with the data lines receive scan pulses. The high level driving voltage source generates high level driving voltages. The source-follower circuit varies the voltage of a second node according to the voltage of a first node. The OLED element is connected between a second node and a base-voltage source and is turned on by the voltage of the second node. The offset capacitor is connected between first and third nodes. The switch circuit supplies the data voltages to the first node during a first period, stores an offset voltage in the offset capacitor through a short circuit between the second and third nodes, supplies the data voltages to the third node during a second period, increases the voltage level of the first node, equalizes the voltage of the second node and the data voltages, and maintains the voltage of the second node as the data voltages during a third period. |
