DISPLAY DEVICE AND METHOD OF OPERATING THE SAME

A display device includes pixels having gate lines, data lines, dummy pixels each of which is connected to a dummy gate line, a dummy data line or one of a corresponding data line of the data lines, a gate driver configured to drive the gate lines and the dummy gate line, a data driver configured to drive the data lines and the dummy data line, a timing controller configured to control the gate driver to drive the dummy gate line and apply a test data to the data driver during a test mode, a kickback detector configured to output a kickback signal corresponding to a difference between the test data and a digital detecting signal of the dummy pixel during the test mode, and a voltage generator adjusting a level of a common voltage in accordance with the kickback signal.