A current supply includes a current mirror arrangement having a feedback
circuit. The current supply includes a current mirror input stage
connected to a constant current source providing a reference current; a
current mirror output stage providing an output current substantially
mirroring the reference current; and a feedback circuit feeding back to
the current mirror input stage a feedback signal representing
perturbations in the output current to cause the output current to more
accurately mirror the reference current. In one embodiment, a dummy
current mirror output stage substantially mirrors the reference current,
and the feedback circuit receives a signal from the dummy current mirror
output stage, and in response thereto, supplies the feedback signal to
the current mirror input stage to cause the output current to more
accurately mirror the reference current.