Agilent Technologies E5382A, Руководство пользователя

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Operating the Probe
Grabber Clip and Right-angle Ground Lead
Step input
Maintaining signal fidelity to the logic analyzer is critical if the analyzer is to
accurately capture data. One measure of a system's signal fidelity is to compare
V
in
to V
out
for various step inputs. For the following graphs, V
in
is the signal at
the logic analyzer probe tip measured by double probing with an Agilent 54701A
probe into an Agilent 54750A oscilloscope (total 2.5 GHz BW). Eye Scan is used
to measure V
out
, the signal seen by the logic analyzer. The measurements were
made on a mid-bus connection to a 50
Ω
transmission line load terminated at the
receiver. These measurements show the logic analyzer's response while using
the grabber clip and right-angle ground lead configuration.
Step measurement schematic
The following graphs demonstrate the logic analyzer's probe response to
different rise times. These graphs are included for you to gain insight into the
expected performance of the different recommended accessory configurations,
particularly for the grabber clip and right-angle ground lead configuration. As
the following graphs will demonstrate, the use of the undamped grabber clip
results in excessive overshoot and ringing at the logic analyzer for targets with
< 1 ns rise times.
E5382A
Probe
Z0=50 Ω
Rterm
Driver Receiver
Rsource
Step
output
50
Ω
Z0=50 Ω
50 Ω
Logic
Analyzer
w/ EyeScan
Oscilloscope
2.5GHz BW
incl. probe
54701A
Probe