Accurate ADC dynamic testing by means of the three-parameter sine-fit algorithm

In this paper it is shown that the effective number of bits (ENOB) of an analog-to-digital converter (ADC) can be accurately estimated by means of the three-parameter sine-fit algorithm, when the normalized frequency is a priori estimated by the interpolated discrete Fourier transform (IpDFT) method with maximum sidelobe decay windows. A criterion for optimal window choice is proposed. In addition, a constraint on the number of acquired samples is derived. It ensures that the random errors of the normalized frequency estimates due to the quantization noise on the ENOB estimates are practically neglected. Performed simulations confirmed that when the window is chosen by the proposed criterion and the number of samples satisfies the derived constraint, accurate ENOB estimates are obtained. Finally, some experimental results are shown by means of a graphical interface specially development for this purpose.