Article

Influence of frequency errors in the variance of the cumulative histogram [in ADC testing]

Dept. of Electr. & Comput. Eng., Tech. Univ. Lisbon
IEEE Transactions on Instrumentation and Measurement (Impact Factor: 1.71). 05/2001; DOI: 10.1109/19.918166
Source: IEEE Xplore

ABSTRACT In this paper, the calculation of the variance in the number of
counts of the cumulative histogram used for the characterization of
analog-to-digital converters (ADCs) with the histogram method is
presented. All cases of frequency error, number of periods of the
stimulus signal, and number of samples are considered, making this
approach more general than the traditional one, used by the IEEE
1057-1994 standard, where only a limited frequency-error range is
considered, leading to a value of 0.2 for the variance. Furthermore,
this value is an average over all cumulative histogram bins, instead of
a worst-case value, leading to an underestimation of the variance for
some of those bins. The exact knowledge of this variance allows for a
more efficient test of ADCs and a more precise determination of the
uncertainty of the test result. This calculation was achieved by
determining the dependence of the number of counts on the sample phases,
on the transition voltage between codes, and on the stimulus signal
phase

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