Source driver and display device having the same

A source driver of a display device is provided to improve the driving efficiency of an element by generating exact current or voltage, and reduce the manufacturing cost by improving the production yield. A gamma reference voltage generating unit(1200) comprises a gamma control part(1210), a standard voltage supply unit(1220), a voltage generation part(1230), and an output buffer part(1240). A gamma control unit generates a plurality of gamma control signals which controls the output of the voltage generation part. A reference voltage supplier provides the reference voltage(Vref) to the voltage generation part. A voltage generation part produces a plurality of gamma reference voltage according to gamma control signal of the gamma control part, and the reference voltage supplier's reference voltage. An output buffer part provides a plurality of gamma reference voltages(VGref-1 or VGref-j) for the gamma signal feed port(1100).