Agilent Technologies InfiniiVision 3000 X- Series Advanced Training Manual page 51

Your scope's display should now look similar to
scope's default rising edge type trigger, we can see two distinctly different
rising edge speeds on this waveform. Also notice that the slower
transitioning edge appears dimmer. This is because the slower
transitioning edges occur less often than the faster transitioning edges.
Perhaps these slower transitioning edges are in violation of meeting
minimum required specifications. Let's first set up the scope to measure
the rise times of this signal, and then we will set up the scope to uniquely
trigger on the violation edges.
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Figure 32 The scope's measurement statistics shows the range of rising edge speeds on
Looking at the on- screen Rise Time measurement statistics, we can see
that the scope is measuring a minimum Rise Time in the range of 50 ns,
while also measuring a maximum Rise Time in the range of 125 ns as
shown in Figure 32. If we assume that our system specification requires
that signal edge speeds (based on 10% to 90% threshold levels) must be
faster than 100 ns, then we have just detected a signal integrity problem
with our design. To further troubleshoot this issue we should set up our
scope to uniquely trigger on just the edges that are in violation. This might
help us isolate what the root cause might be that is causing these
3000 X-Series Oscilloscopes Advanced Training Guide
Advanced Triggering, Search & Navigation, and Segmented Acquisition Labs
Press [Meas]; then press the Type softkey.
Turn the Entry knob to point to the Rise Time measurement; then either
push the Entry knob or press the Add Measurement softkey.
this signal.
Figure 31. Using the
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