In a data line driver for driving data lines of a display apparatus including a data register adapted to sequentially latch video data signals in synchronization with latch signals, a data latch circuit adapted to latch all the sequential video data signals latched in the data register in synchronization with a strobe signal to generate digital output signals, a digital/analog converter adapted to convert the digital output signals of the data latch circuit into analog signals, and an output buffer adapted to apply the analog signals of the digital/analog converter to the data lines, the data latch circuit has a reset terminal adapted to receive a reset signal, so that the digital output signals of the data latch circuit are reset by the reset signal to fixed gradation data regardless of the strobe signal.