A digital-to-analog converter is described. The digital-to-analog
converter converts an m-bit digital signal into an analog signal using m
weighted currents, such as m binary-weighted currents. A first weighted
current may be calibrated using a reference current. The first weighted
current may be compared to the reference current, and a control signal,
controlling the first weighted current, may be generated to adjust the
first weighted current to be substantially equal to the reference
current. The first weighted current may then be compared with another of
the m weighted currents (such as a second weighted current). The
comparison may be used to further calibrate the first weighted current or
to calibrate the second weighted current.