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InfiniiMax RC Probe Amplifier and Probe Heads User’s Guide
10
N5425B InfiniiMax Differential ZIF Probe Head
N5425B Input Impedance
This section provides:
• the SPICE model for N5425B probe head with N5426A and N2884A ZIF tips
attached. This SPICE model is only for input impedance which allows modeling
of the probe loading effects. Probe transfer function is generally flat to the
specified bandwidth.
• input impedance plots for N5425B probe head with N5426A and N2884A ZIF
tips attached. to show the matching of the measured data to the modeled data.
Matching is generally very good up to the specified bandwidth of the probe
head.
NOTE
Input impedance is a function of the probe head only. The probe amplifier
bandwidth (25 GHz) does not have any effect on the input impedance of
the probe head.
NOTE
Refer to the chapter
“InfiniiMax RC Probe Amplifier and Probe
on page 143 to get a typical corrected
frequency response and CMRR for the MX0023A probe amplifier and probe
head combination.