A display interface device capable of reducing power consumption is disclosed. In the display interface device, a timing controller configured to compare input pixel data in horizontal line units and operate in a low power mode according to a result of comparison between an input time of horizontal lines having the same pixel data and a reference time in the horizontal line units. The timing controller operates in any one of a first low power mode for transmitting a training pattern and a second low power mode including a first duration during which data transmission and reception are stopped and a second duration during which the training pattern is transmitted, according to the result of comparison between the input time of horizontal lines having the same pixel data and the reference time.