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

4
Operating the E5402A, E5405A, and E5406A-Pro Series Probes

Equivalent Probe Loads

48
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.
PC board pads are not included.
L11
D1
0.63nH
C12
0.280pF
Cm12 Rgnd1
0.070pF 0.5Ω
L21
D0
0.63nH
C22
0.280pF
Rgnd2
0.5Ω
Figure 28 Probe load model (E5402A, E5405A, and E5406A)
Cshnt1
.350pF
L12 Rtip1
1.17nH 20KΩ
Cshnt2
.350pF
L22 Rtip2
1.17nH 20KΩ
E5400-Pro Series Soft Touch User's Guide
Rtrm1
75Ω
+0.75V
Rtrm2
75Ω
+0.75V