Patent ID: 7898511

Claim:
An organic light emitting diode display, comprising: a light emitting cell connected between a high-level voltage source and a first node, wherein the light emitting cell is located in each of m×n pixel areas defined by m data lines and 2n gate lines; a driving transistor connected between the first node and a ground voltage source to control a current flow in the light emitting cell, by using a voltage applied to a gate terminal of the driving transistor; a data driving circuit configured to apply a data voltage of first polarity to the gate terminal of the driving transistor through the data lines to shift a threshold voltage of the driving transistor from a reference value to the voltage of first polarity; and a compensation circuit configured to supply a compensation voltage of second polarity, which is different from the first polarity, to the gate terminal of the driving transistor to shift the threshold voltage of the driving transistor from the voltage of first polarity to the voltage of second polarity, and supply a constant current to the gate terminal of the driving transistor to restore the threshold voltage of the driving transistor to the reference value, wherein output terminals of the data driving circuit and the compensation circuit are connected to the data lines, and wherein the compensation voltage is supplied to the gate terminal of the driving transistor through the data lines and then the constant current is supplied to the gate terminal of the driving transistor through the data lines.