A device for driving a display apparatus includes a scan driver, a timing circuit and a data driver. The scan driver generates a plurality of scan signals activating the scan lines. The timing circuit generates a control signal. The data driver samples a first gray scale voltage signal in response to the control signal, and generates a second gray scale voltage signal to provide a display panel of the display apparatus with the second gray scale voltage signal. The second gray scale voltage signal has a sampled voltage level of the first gray scale voltage signal, and the sampled voltage level is synchronized with the control signal. The deterioration of the display quality due to ripples may be reduced.