Abstract: A method and apparatus for the calibration of current cells, whereby a current signal from each current cell may be generated by either a thermometer current cell, or a binary current cell. If generated by a binary current cell, then two or more replica binary current cells exist to form a group of binary current cells within two or more binary current cell sets. The current magnitude generated by each replica current cell of each binary current cell group is first calibrated to be substantially equal to each other. Next, the combined current generated by the replica current cell group is calibrated to be substantially equal to a magnitude of a temporary current signal, or a portion thereof. Subsequent less-significant binary current cell groups are similarly calibrated to the temporary current signal through the use of the previously calibrated, more-significant binary current cell groups.

Abstract: A method and apparatus for calibrating a current source to a reference current through the use of 1-bit current comparisons. A temporary current source is first calibrated to the reference current, which allows an input offset current generated by the current comparator to be memorized. The current to be calibrated is then fine-tuned to the temporary current within specified limits, which effectively cancels comparison error that is generated by the input offset current.