A method for determining data signal jitter via asynchronous sampling
provides a low cost and production-integrable mechanism for measuring
data signal jitter. The data signal is edge-detected and sampled by a
sampling clock of unrelated frequency the sampled values are collected in
a histogram according to a folding of the samples around a timebase. The
timebase is determined by sweeping to detect a minimum jitter for the
folded data. The histogram for the correct estimated timebase period is
representative of the probability density function of the location of
data signal edges and the jitter characteristics are determined by the
width and shape of the density function peaks. Frequency drift can be
corrected by adjusting the timebase used to fold the data across the
sample set.