LeCroy DDA 7 Zi series, Руководство оператора

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Operator's Manual
WP700Zi-OM-E-RevA
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Relative Peak
Accessing JTA2
To access JTA2's special features, you must first purchase and install the option . Once installed, JTA2's math
and parameter selections will appear in the Math and Measure menus.
Timing Functions
JitterTrack,PersistenceHistogramandPersistenceTrace are timing functions in LeCroy’s JitterPro and JTA jitter
and timing analysis packages. The JitterTrack feature is key to identifying the source of excessive jitter or non-
normal jitter characteristics. A timeline of signal jitter that is synchronous with the signal under test allows you to
view patterns that would remain invisible using other systems, zoom to areas containing maximum jitter, and
troubleshoot the problem. PersistenceHistogram is the ideal quantitative "companion" to persistence display. It
histograms a horizontal or vertical slice of the persistence waveform. Utilizing averagerange and sigma, , settings,
PersistenceTrace computes a vector trace from a bit map to give insight into edge details down to a few
picoseconds.
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JitterTrack graphically plots as a function of time the amplitude of the waveform attributes Cycle-to-Cycle
variation, Duty Cycle , Interval Error , Period , Width , and Frequency .
Interval Error, for example, calculates the timing error of a signal compared with an ideal, expected interval
defined by a user-specified reference frequency, the most common estimator of jitter. "The short-term
variations of a digital signal’s significant instants, from their ideal positions in time," are plotted. This is the
perfect tool for characterizing clocks in synchronized telecom networks such as SONET and SDH.
A special data function, available for most of these attributes, enables work on random data streams.
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Persistence Histogram analyzes a vertical or horizontal slice of a persistence map of multiple waveforms.
The resultant bar chart shows a numerical measurement of the timing variations of a signal, which are
observed qualitatively in the persistence display of the signal. A typical application is characterizing the
jitter in a communications signal eye diagram.
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Persistence Trace is a method for displaying the data acquired from multiple sweeps of a waveform. A
vector trace is computed, based on the bit map of the underlying multiple signal acquisitions. Detail is then
represented in a choice ofthree graphic