LeCroy DDA 7 Zi series, Руководство оператора

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WavePro 7Zi
297
WP700Zi-OM-E-RevA
CLOCK
EDGE
DATA SLOPE
Positive Negative
Positive
times between edges of positive polarity
subject pit and nearest positive clock edge times between edges of negative polarity
subject space and nearest positive clock edge
Negative
times between edges of positive polarity
subject pit and nearest negative clock edge times between edges of negative polarity
subject space and nearest negative clock edge
Near
times between edges of positive polarity
subject pit and nearest clock edge times between edges of negative polarity
subject space and nearest clock edge
The next figure demonstrates the measurement of the beginning edge shift on a single subject 4T pit preceded
and followed by a 3T space. In this example, the clock is specified as the positive edge. The beginning edge shift
is calculated as the time difference between the beginning pit edge and the clock edge while the ending edge shift
is calculated as the time difference between the ending pit edge and the clock edge.
Figure 5-7. Beginning and Ending Edge Shift measurement of subject 4T pit
The measurement has configurable units. If absolute time is specified, the value is simply the time, as indicated
above. If percent is specified, the value of the measurement is the time normalized to the clock period:
For all pits, a valid measurement will be obtained only when both edges of the leading and trailing pits/spaces can
be determined (that is, there is a hysteresis-qualified threshold crossing beginning the start pit/space and ending
the end pit/space of interest between the parameter cursors), and there is a clock edge of both polarities
surrounding the leading pit or space edge between the parameter cursors.
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 average time between the edges of the subject n pit (space) and
nearest clock edges for all subject pits (spaces) that are preceded and followed by the
specified space (pits) for the last acquisition.
Parameter
Statistics On
Average, minimum, maximum, and sigma of the beginning and ending edge shift calculated
for all subject pits (spaces) that are preceded and followed by the specified space (pits) for
all acquisitions since the last CLEAR SWEEPS operation.
nT Table
List of values of the beginning edge shift and the ending edge shift for all subject pits