A data driver includes a positive-polarity reference voltage generation circuit that outputs positive-polarity reference voltages, a positive-polarity decoder that receives the positive-polarity reference voltages from the positive-polarity reference voltage generation circuit, end selects and outputs at least one positive-polarity reference voltage in accordance with first digital data, a positive-polarity amplifier which includes a first differential units that receives the selected reference voltage selected by the positive-polarity decoder, performs amplification, and outputs a voltage to a first amplifier output terminal, .delta. negative-polarity reference voltage generation circuit that outputs negative-polarity reference voltages, and a negative-polarity decoder that receives the negative-polarity reference voltages from the negative-polarity reference voltage generation circuit, and selects and outputs at least one negative-polarity reference voltage in accordance with second digital data.