A driver for a display panel includes a driving time accumulator, a ditherer, and a data signal generator. The driving time accumulator determines an accumulated driving time of the display panel. The ditherer determines an amount of dither based at least in part on the accumulated driving time, and performs a dithering operation on input image data with the determined amount of dither. The data signal generator generates a data signal for the display panel based at least in part on the input image data on which the dithering operation is to be performed.