A low-complexity dynamic element matching technique for reduced-distortion digital-to-analog conversion

This paper presents a dynamic element matching (DEM) technique for low harmonic distortion digital-to-analog converters (DACs). The technique employs simple binary switches controlled by pseudo-random bit sequences to make appropriate selections in a bank of unit DAC-elements whose outputs are summed to form the output of the composite DAC. Harmonic distortion resulting from static mismatches of the unit DAC-elements is eliminated at the expense of an increased noise floor. A comparison with previously reported DEM techniques for low harmonic distortion DACs shows that the technique proposed here is of least hardware complexity. For example, for DAC resolutions of 5 bits or greater, the proposed scheme uses about 50% fewer binary switches than the most hardware efficient prior art.