Teledyne LeCroy SDA II - Manual (Page 4)

Serial Data Analysis II Software
SDAII Overview
The new Serial Data Analyzer (SDAII) provides comprehensive measurement capabilities for evaluating
serial digital signals. SDAII operates by processing a long signal acquisition. All jitter measurements and
displays are based on times of successive edges for the signal only - nothing is relative to the trigger. As a
result, they are not affected by trigger jitter. Acquisitions should be long enough to include at least 100,
000 UI of the signal under test (500,000 UI or more is optimal). It may be desirable to acquire longer rec-
ords to see low frequency jitter.
Note: Acquisitions can be up to the full available memory depth of the instrument and may take con-
siderable time to process.
The SDAII processes include clock recovery, eye pattern measurement, and jitter measurement. These
operations are performed on the same data record.
Key Features
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SDAII provides two types of measurements: eye pattern testing and comprehensive jitter anal-
ysis (including random and deterministic jitter separation, and direct measurement of periodic
jitter, DDj, and DCD).
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Many plot types for jitter and eye diagram analysis, including eye diagram, IsoBER, DDj Plot, dig-
ital pattern, DDj Histogram, jitter track, PLL track, jitter spectrum (with peak annotation), spec-
trum threshold, Pj Inverse FFT, jitter histogram, CDF, bathtub and Normalized Q-scale fit.
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Filtered jitter processes the time interval error trend versus time with a user-selectable band-pass
filter. This feature allows applying filters in addition to the high-pass filtering effect of the clock
recovery PLL, which is required for some serial data specifications.
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IsoBER displays the extrapolated lines of constant Bit Error Ratio down to the BER of interest on an
eye diagram.
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Quick View provides a shortcut displaying the eye diagram, TIE track, bathtub curve, jitter his-
togram, NQ-scale cursors, and jitter spectrum all on the screen at the same time.
Serial Data Analysis II Dialog
Access the SDAII dialog by choosing Analysis → Serial Data.
The Serial Data Analysis II dialog shows the overall flow for viewing and analyzing serial data. Each block
in the flow diagram is a button that, when touched, displays its corresponding dialog.
The multiplexer switch button (on the Setup Clock Recovery button's respective dialog) allows you to
select clock recovery from the input data signal or, in the down position, a separate explicit clock signal.
Touch the multiplexer switch button to change the state.
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