A low power analog-to-digital channel includes a decimation filter coupled to a sigma-delta modulator. The control signals are derived based on information obtained from the image sensor as well as other detected parameters pertaining to the detected light source, the vehicle having the inventive control system, and the ambient environment. One polishing system embodiment includes a platen adapted to receive a wafer, and a polishing pad drum that has a cylindrical, or generally cylindrical, shape with a length and an axis of rotation along the length.