DATA-DIRECTED SCRAMBLER FOR NOISE-SHAPING MIXED-SIGNAL CONVERTERS WITH AN ARBITRARY NUMBER OF QUANTIZATION LEVELS

Methods and apparatus are provided for processing N equally-weighted digital signals, where N is an arbitrary integer not necessarily an integer power of 2. The invention is particularly useful in noise-shaping, mixed-signal converters. The apparatus includes a rotator for rotating the N equally-weighted digital signals in a sequence of rotator states in respective clock cycles to provide N rotated digital signals, and a data-directed scrambler having N inputs and N outputs for data-directed scrambling of the rotated digital signals to distribute the N equally-weighted digital signals to each of the N outputs of the scrambler such that the usage of the N outputs is dynamically balanced over a relatively small number of clock cycles, leading to a shaped noise spectrum.