A display device includes the following elements: a display panel comprising pixels; a data driver supplying data signals to the plurality of pixels; a driving voltage supply supplying a first driving voltage to the data driver; a power supply supplying a first input driving voltage to the driving voltage supply; and a timing controller providing control signals to the data driver, the driving voltage supply, and the power supply and providing luminance information and per-second frame rate information of the display panel to the driving voltage supply. The driving voltage supply comprises an input driving voltage adjuster which adjusts the first input driving voltage to a second input driving voltage based on the luminance information and the per-second frame rate information.