Equivalent Probe Loads - Agilent Technologies E5406A-Pro Series User Manual

3
Operating the E5404A-Pro Series Probes

Equivalent Probe Loads

(Does not include capacitive coupling between channels or inductance of the spring pins)
(Includes capacitive coupling between channels and inductance of spring pins.)
Din
42
The following probe load models are based on in- circuit
measurements made with an Agilent 8753E 6 GHz network
analyzer and an Agilent 54750A TDR/TDT using a 50 Ω test
fixture. The following schematic accurately models the probe
load out to 6 GHz. The figure on the following page shows
the agreement between measured impedance and this model.
Din
Cstub
0.375pF
Lspring1
0.63nH
Ccoupling
0.070pF
Figure 21
Simple
Rtap
400Ω
Rtip
100kΩ
Complex
Lspring2
1.17nH
Cstub
0.375pF
100kΩ
Rgnd1
10Ω
Probe load models (E5404A)
E5400-Pro Series Soft Touch User's Guide
Ctip
10pF
Rtip1
250Ω
Ctip
10pF
Rtip2
Rgnd2
120Ω