5968-4632E Datasheet, PDF (33/77 Pages) Keysight Technologies – Probing Solutions for Logic Analyzers

33 | Keysight | Probing Solutions for Logic Analyzers - Data Sheet
Probing Solutions for 90-pin Logic Analyzers
Soft Touch Connectorless Probing (Continued)
Equivalent probe loads
The following probe load models are based on in-circuit measurements made with a
Keysight 8753E 6 GHz network analyzer and a Keysight 54750A TDR/TDT using a 50 Ω
test fixture. The following schematic accurately models the probe load out to 6 GHz. PC
board pads are not included.
D1
Cm12
0.070 pF
D0
L11
0.63 nH
C12
0.280 pF
Rgnd1
0.5
L21
0.63 nH
C22
0.280 pF
Rgnd2
0.5
L12
1.17 nH
L22
1.17 nH
Cshnt1
.350 pF
Rtip1
20 K
Rtrm1
75
Cshnt2
.350 pF
Rtip2
+0.75 V
20 K
Rtrm2
75
+0.75 V
Figure 4.26. Equivalent probe load model.