ADC spectral performance measurement uncertainty in DFT method

Spectral performances are important specifications need to be measured for many analog and RF circuits. Measurement errors of these performances are random variables related to additive noise which is normal distributed. Few research results on measurement error can be found in literature. Therefore accuracy or error of measurement is usually estimated by experience. This paper presents rigorous analyses of measurement error of THD and SFDR in DFT testing. Analyses are validated by Matlab simulations and provide useful guidance on how to select number of samples to achieve certain accuracy and confidence level in real testing.