A flat panel display is provided in which a controller generates gamma data digitized for each gradation and transmits the same to column driver ICs, which then generate gradation voltage by using gamma data and output column signals. Here, the gamma data can be transmitted in TTL system or differential signal transmission system. Thus, the number of transmission lines can be reduced since column driver ICs generate the gradation voltage by utilizing gamma data produced from the controller and output a column signal. As a consequence, a control board can be configured in an easy manner while at the same time reducing manufacturing costs. Further, a high precision image representation, low power consumption, and high speed data transmission can be obtained while at the same time eliminating EMI trouble.