Reference
80E00 ElectricalSampling Modules User Manual 45
If thewaveform top is bowed, sagged, hooked, or tilted, assume static has
damaged themodule and service is required. Figure 17 on page 45 shows a
typical waveformsignature indicating EOS damage.
Also be awarethat EOS can be cumulative; that is, every time an EOS event
occurs during testing, EOS d amage can accumulate until there is even greater
damage, as shown in Figure18 on page 46. In this example, the percentage of
overshoot is increased.
Tocheck for damage, use one of the following procedures:
If checkingan 80E04 sampling module and your instrument has TDR capability,
attach a 50 Ωtermination to the channel input andperform a TDR measurement
of the attachedfitting:
1. Select the TDR channelto turn it on.
2. Pressthe TDR preset.
3. Adjust the HORIZONTALSCALE to 2 µs per division. The vertical setting
should be 200 mρas shown in the illustrations.This should display the
entire TDR step fromedge to edge. Display the step top at 40 mρper
division and checkfor flatness. The top of the waveform should be flat.
If checkinga non-TDR sampling module, use a proceduresimilar to the
preceding procedure, but use an external step source.
1.995p
200mp
/div
trig’d
T
--2.005p
T
261.7ns 2s/div 20.26s/div
EOSsignature
Figure17: Firstexample of EOS error
Checking For Damage