Patent ID: 7999771

Claim:
An organic light emitting display comprising: a plurality of column lines adapted to receive a drive current, each of the column lines belonging to one of a plurality of groups; a plurality of row lines adapted to receive a scan signal; a plurality of organic light emitting diodes of a plurality of pixels, which are located at crossings of the row lines and the column lines; a scan driver for applying the scan signal to the row lines; a data driver including a common current source and a plurality of drive switching elements, the common current source being adapted to apply the drive current to the column lines in one of the groups, and the drive switching elements being electrically connected to the common current source and being adapted to apply the drive current to the column lines in said one of the groups within a drive period in which the scan signal is applied; a plurality of charge switches electrically connected to the column lines, the charge switches being turned-on before the drive current is applied to the column lines, and being turned-off during the drive period; and a voltage retaining circuit coupled with the charge switches, for preliminarily charging the pixels, wherein the drive current comprises a first driving current applied to one of the column lines during a first period of the drive period, and a second driving current applied to the one of the column lines during a second period of the drive period, wherein the second driving current has a lower magnitude than a magnitude of the first driving current, wherein the drive current is not applied to the one of the column lines during a third period of the drive period, and wherein the second driving current is applied to the one of the column lines during a fourth period of the drive period.