Predicting and Avoiding Spurious Tones in a DWA-Mismatch-Shaping DAC

A data-weighted-averaging (DWA) algorithm provides a simple realization of the first-order mismatch shaping of digital-to-analog-converter (DAC) errors. A drawback of DWA is the tendency for generating spurious tones. This brief proposes an analytical model for mismatch-noise tone behavior. The model explains how the spurious tones depend on the stimulus and the DAC error shape. It is also shown that the in-band spurious tones can be minimized by altering the differential-nonlinearity-error shape simply by rearranging the unit elements.