Data driver and display device

A data driver comprising:

• a positive-polarity reference voltage generation circuit that outputs a plurality of positive-polarity reference voltages having mutually different potentials;
• a positive-polarity decoder that selects and outputs at least one reference voltage in accordance with an input first digital signal from among the positive-polarity reference voltages;
• a positive-polarity amplifier including:
• a first differential unit that receives at least one reference voltage selected by said positive-polarity decoder;
• and a first output stage that receives an output of said first differential unit, performs amplification, and outputs a voltage to a first amplifier output terminal;
• a negative-polarity reference voltage generation circuit that outputs a plurality of negative-polarity reference voltages having mutually different potentials;
• a negative-polarity decoder that selects and outputs at least one reference voltage in accordance with an input second digital signal from among the negative-polarity reference voltages;
• a negative-polarity amplifier including:
• a second differential unit that receives at least one reference voltage selected by said negative-polarity decoder;
• and a second output stage that receives an output of said second differential unit, performs amplification, and outputs a voltage to a second amplifier output terminal;
• and
• an output switch circuit that performs switching between straight connection of said first and second amplifier output terminals to first and second driver output terminals, respectively and cross connection of said first and second amplifier output terminals to said second and first driver output terminals, respectively, responsive to a control signal;
• said data driver being supplied with voltage supplies including a high-potential voltage supply, a low-potential voltage supply, and an intermediate-potential voltage supply having a potential intermediate between the high-potential voltage supply and the low-potential voltage supply;
• wherein the high-potential voltage supply and the low-potential voltage supply are provided to said first differential unit in said positive-polarity amplifier;
• the high-potential voltage supply and the intermediate-potential voltage supply are provided to said at least first output stage, excluding said first differential unit in said positive-polarity amplifier;
• the high-potential voltage supply and the low-potential voltage supply are provided to said second differential unit in said negative-polarity amplifier;
• and
• the intermediate-potential voltage supply and the low-potential voltage supply are provided to said at least second output stage, excluding said second differential unit in said negative-polarity amplifier.

A digital-to-analog converter circuit comprising:

• a first digital-to-analog converter unit that performs conversion to produce a first analog voltage corresponding to an input first digital signal and outputs the first analog voltage to a first terminal thereof;
• and
• a second digital-to-analog converter unit that performs conversion to produce a second analog voltage corresponding to an input second digital signal and outputs the second analog voltage to a second terminal thereof;
• said first digital-to-analog converter unit comprising:
• a positive-polarity decoder that selects and outputs at least one positive-polarity reference voltage corresponding to the first digital signal from among a plurality of positive-polarity reference voltages output from a positive-polarity reference voltage generation circuit;
• and
• a positive-polarity amplifier including a first differential unit that receives at least one positive-polarity reference voltage selected by said positive-polarity decoder and a first output stage that receives an output of said first differential unit, performs amplification, and outputs the voltage to said first terminal;
• said second digital-to-analog converter unit comprising:
• a negative-polarity decoder that selects and outputs at least one negative-polarity reference voltage corresponding to the second digital signal from among a plurality of negative-polarity reference voltages output from a negative-polarity reference voltage generation circuit;
• and
• a negative-polarity amplifier including a second differential unit that receives at least one negative-polarity reference voltage selected by said negative-polarity decoder, and a second output stage that receives an output of said second differential unit, performs amplification, and outputs the voltage to said second terminal;
• said digital-to-analog converter circuit further comprising:
• an output switch circuit that performs switching between straight connection of said first terminal of said first digital-to-analog converter unit and said second terminal of said second digital-to-analog converter unit to said first output terminal and said second output terminal, respectively and cross connection of said second terminal of said second digital-to-analog converter unit and said first terminal of said first digital-to-analog converter unit to said first output terminal and said second output terminal, respectively;
• said digital-to-analog converter circuit being provided with voltage supplies including a high-potential voltage supply, a low-potential voltage supply, an intermediate-potential voltage supply having a potential between the high-potential voltage supply and the low-potential voltage supply being supplied as a voltage supply;
• wherein
• the high-potential voltage supply and the low-potential voltage supply are provided to said first differential unit of said positive-polarity amplifier;
• the high-potential voltage supply and the intermediate-potential voltage supply are provided to said at least first output stage excluding said first differential unit;
• the high-potential voltage supply and the low-potential voltage supply are provided to said second differential unit of said negative-polarity amplifier;
• and
• the low-potential voltage supply and the intermediate-potential voltage supply are provided to said at least second output stage excluding said second differential unit.