Nonlinear distortion in current-steering D/A-converters due to asymmetrical switching errors

Asymmetrical switching errors introduce even harmonic distortion products in the differential output signal of a current-steering NRZ D/A-converter. Dynamic element matching techniques, originally intended to shape the mismatch induced nonlinearity into wide-band noise, can even worsen the dynamic performance of such converters due to their increased switching activity. A simple mathematical model to formalize this effect is presented and verified with simulations.

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