User`s guide

Histogram In-depth Description
The SIA-3000™ asynchronously measures times between threshold crossings.
fall time = t
2
These "hits" are made randomly. This randomization ensures that no jitter would be masked out by a
constant sampling rate. Each hit, or time sample, is then binned into a histogram. The histogram is
complete once the number of Hits per Measure has been reached. Additionally, the
SIA-3000™ is not
triggered. Triggered instruments can mask out jitter if the signal used to trigger is derived from the circuit
under test.
See the following examples:
Example 1 is a histogram of a good clock.
Example 2 is a bimodal histogram with equal heights.
Example 3 is a bimodal histogram with unequal heights.
© WAVECREST Corporation 2005 Section 4 - GigaView
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