LeCroy DDA 7 Zi series, Руководство оператора

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Operator's Manual
WP700Zi-OM-E-RevA
300
Dp2cs - DELTA PIT TO CLOCK SIGMA
Description
Dp2cs provides a measurement of the mean, normalized standard deviation of the Delta Pit-to-Clock
measurements (see
Dp2c ). When a single n is specified, or in ‘nT Table’ Show mode, the value calculated for the
nth index is calculated using the following equation for standard deviation:
Delta Pit-to-Clock Sigma cannot be calculated for a given index n unless there are at least two Delta Pit-to-Clock
values calculated for that n index.
When Delta Pit-to-Clock is configured as a custom parameter with a range of n , the value calculated is the
standard deviation of the distribution that results by normalizing each independent distribution categorized by nT.
Distributions are normalized by subtracting the mean of the distribution from all of the elements in the distribution.
This results in the following equation for overall Delta Pit-to-Clock Sigma resulting from the individually
categorized Delta Pit-to-Clock Sigma values:
Note: The value calculated by DP2CS will generally not be the same as the sigma of DP2C measurement
displayed on the parameter line when a range of n is used and statistics is on. This is because the two
measurements are not the same. DP2CS measurement normalizes the results for each n by subtracting the
mean DP2C from each DP2C in the nth distribution. This results in a superposition of mean centered
distributions, not a superposition of 0 centered distributions contributing to DP2C measurements. DP2CS will
always be less than or equal to the standard deviation of DP2C measurements.
Display Options
ORM parameter calculations can be displayed, histogrammed, and trended in a variety of ways.
DISPLAY TYPE VALUE DISPLAYED
Parameter
Statistics Off Single value of the standard deviation of the mean normalized Delta Pit-to-Clock values
for pits/spaces of interest for last acquisition.
Parameter
Statistics On Average, minimum, maximum and sigma of the Delta Pit-to-Clock sigma value calculated
per acquisition for all acquisitions since the last CLEAR SWEEPS operation.
nT Table
List of values of the standard deviation of the Delta Pit-to-Clock values for each individual
‘nT’ in the selected range of ‘nT’ for the last acquisition.
Histogram
Function
Histogram of Delta Pit-to-Clock sigma values calculated for each acquisition for all
acquisitions since the last CLEAR SWEEPS operation.
Trend Function
Trend of the Delta Pit-to-Clock sigma values calculated for each acquisition for all
acquisitions since the last CLEAR SWEEPS operation.