A source driver includes an interpolation amplifier configured to generate an interpolation voltage based on a received plurality of input voltages and output the interpolation voltage to a display panel; and an input selector configured to receive a first voltage and a second voltage having a different level from the first voltage, and configured to selectively provide at least one of the first and second voltages as the plurality of input voltages in response to some of the lower bits of pixel data. The interpolation amplifier includes four conductive differential input pairs configured to receive four input voltages from among the plurality of input voltages, respectively. Each of the first differential input pair and third differential input pair comprises a first type transistor. Each of the second differential input pair and fourth differential input pair comprises a second type transistor.