Patent ID: 8471876

Claim:
An organic electroluminescent display device, comprising: a display panel that includes a plurality of sub-pixels which include a plurality of organic light emitting diodes, respectively, to display a frame image made by a plurality of image data by every frame; a data drive IC that outputs a plurality of data voltages to the plurality of sub-pixels, respectively, by every frame, wherein the plurality of data voltages correspond to the plurality of image data, respectively; a current detecting portion that detects a first panel current, which is a total of currents applied to the plurality of organic light emitting diodes during a frame, and generates a first comparison value corresponding to the first panel current; a current estimating portion that estimates a second panel current from the plurality of image data of the frame and generates a second comparison value corresponding to the second panel current, wherein the second panel current is a total of currents expected to be applied to the plurality of organic light emitting diodes during the frame; and a brightness control portion that compares the first and second comparison values and adjusts a brightness of a frame image after the frame according to the comparison result obtained by the brightness control portion, wherein the brightness control portion includes a comparing portion that compares the first and second comparison values, and a gamma driving voltage adjusting portion that adjusts a gamma driving voltage supplied to one end of at least one resistor string of a gamma voltage generator according to the comparison result, and wherein when the first comparison value is more than the second comparison value, the gamma driving voltage adjusting portion decreases a level of the gamma driving voltage, and when the first comparison value is less than the second comparison value, the gamma driving voltage adjusting portion increases the level of the gamma driving voltage.