A display device comprises a display panel. The display panel comprises a plurality of gate lines, a plurality of data lines, a plurality of sub-pixels, a gate driver connected to the gate lines, and a data driver connected to the data lines. The data driver comprises a de-multiplexer controller for outputting a plurality of control signals to a plurality of control lines, a data process portion for outputting a plurality of data signals to a plurality of signal lines, and a first de-multiplexer comprising a plurality of switches connected to the de-multiplexer controller through the control lines, the data process portion through at least one of the signal lines, and the sub-pixels through the data lines. Wherein the switches of the first de-multiplexer keep turned on within a first horizontal period.