Teledyne LeCroy WavePro Automation Command - Manual (Page 268)

Automation Command and Query Reference Manual - Control Reference
ShowNQScaleFit Bool
Q scale is a coordinate transformation of the CDF (see ShowLogCDF, above) such that for a
Gaussian distribution, the Q scale lines should be straight, with a slope of 1/sigma, and intercept with
Q = 0 (the top of the grid) at the mean of the Gaussian. If there is only one Guassian (no DJ) then the
left and right sides include the entire populiation, that is, they sum to a total probability of 1.
NQScale is Normalized Q Scale; it is normalized to allow the left and right side tails to each have
arbitrary total probability. If more than one Gaussian is present (that is, if DJ is not zero) then the
NQScale white lines on the left and right will intersect Q=0 with a distance between them that equals
DJ, because they intersect Q=0 at the means of the right and left Gaussians. In addition to the fit lines,
red curves are shown which actually are the right and left CDF transformed to Q Scale. If the white
lines overlap the red curves well, then the right and left sides truly are Gaussian.
Sigma (which is Rj) and rho (which is the fraction of total population used for normalization) are
annotated on the cursor lines.
The default jitter decomposition technique used by SDA2 is Spectral, due to its wide acceptance in the
industry. In general, Spectral decomposition and NQ Scale decomposition will agree well. In the
presense of broad band cross talk (bounded, uncorrelated jitter) Spectral can be fooled into counting
that as RJ. NQ Scale is not fooled by that. If Spectral decomp reads much higher RJ(sp) than NQ
Scale's sigma, it probably indicates the presence of broad band bounded uncorrelated jitter. That is
one reason to look at the NQScale cursors - the sigma values should be close to Rj(sp).
NQ Scale can be used to do the jitter decomposition for the parameters, instead of Spectral, see
app.SDA2.JitterMeasure.Parameters.JitterModel.
Description
ShowRjBUjHisto Bool
This jitter histogram include random jitter (Rj) and bounded uncorrelated jitter (BUj) which includes
periodic jitter (Pj). It does not include data dependent jitter (DDj), which includes intersymbol
interference and duty cycle distortion. The diference between this histogram and the TIE histogram
shows the effect of DDj. See ShowTIEHisto, below.
Description
ShowTIEHisto Bool
This is the histogram of Time Interval Error values. It shows all the jitter. Compare this histogram to
the RjBUj histogram - on the same horizontal scale - to see the effect of DDJ (which is not present in
the RjBUj histogram).
Description
BATHTUB app.SDA2.JitterMeasure.Histogram.BathTub
AxisXRotation Integer
AxisYRotation Integer
ClearSweeps Action
LabelsPosition String
LabelsText String
Persist3DQuality Enum
PersistDotJoined Bool
Persisted Bool
Persistence3d Bool
PersistenceMonoChrome Bool
PersistenceSaturation Integer
PersistenceTime Enum
1-254
918501 RevA