HISTOGRAM
To Measure:
For more information
on this tool, refer
to:
Histogram Quick
Reference Guide
available at
www.wavecrest.com
Measuring Jitter with Histogram tool:
1-sigma, peak-to-peak
•
Press “Tool” to open the main menu
•
Press Clock then Histogram to open the histogram tool.
•
Press the SINGLE/STOP button on the front panel or the top menu. The tool
defaults to make a period measurement (rising edge to the next rising edge). The tool
defaults to a sample size of 10,000 measurements.
Basic statistics displayed on the Histogram Summary View are: Mean, Min, Max, 1-
sigma, peak-to-peak, and number of hits (Figure 2).
Results from the most recent pass are displayed as “Latest” text. Results from
accumulated statistics are display as “ACCUM” text. The Maximum Histogram view
(below) shows all accumulated measurements.
Figure 2 - Histogram Period Measurement
A histogram can be made of PERIOD (+), PERIOD (-), PULSE WIDTH (+) and PULSE
WIDTH (-) measurements.
These Histogram statistics may be sufficient for jitter analysis when no deterministic
jitter is present, but with the addition of DJ, it is helpful to perform a more
comprehensive analysis. When the histogram is Gaussian, the 1-sigma equals the
Random Jitter (RJ). The addition of Deterministic Jitter (DJ) will increase the 1-sigma.
WAVECREST’s
Tail-Fit
TM
algorithm can be enabled to better estimate the true RJ.
Clock Tools Overview
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