User`s guide

DCD + ISI Histogram
This view displays the "normalized accumulation" of all the DCD+ISI measurements taken during each
acquire run.
The width of the plot is normalized to one Unit Interval (UI) of the data period.
This view shows jitter components that are correlated to the data and relates to the DCD+ISI number in
the Summary view.
The plot contains two histograms, one for all the rising edges of the pattern and one for all the falling
edges of the pattern. These two histograms are overlaid on each other so their relative location to
the ideal can be seen.
The x-axis shows time.
The y-axis shows the number of edges that accumulate in each bin of these histograms. Note that there
is one value added to the plot for each edge in one pattern.
If the two histograms are not centered on the same relative time position on the x-axis, this can be an
indication of DCD. It can be also be an indication that the voltage level on the input is not set to the
correct value.
Section 4 - GigaView © WAVECREST Corporation 2005
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