An output stage circuit of a data driver for an display is provided. The circuit includes a current mirror having a first transistor and a current source on a reference current path, having a second transistor on an output current path, wherein the reference and output current paths are commonly coupled to a power line, a capacitor having a first end coupled to the power line and a second end coupled to a gate of the second transistor, a first switch cutting off the output current path during a first period, and a second switch coupling the second end of the capacitor to the current source during the first period.