SPICE models can be used to predict probe loading effects. The models shown here are to be used only for modeling input impedance of Keysight probe heads. Probe amplifiers are not included in these models as their characteristics do not affect input impedance.

If damped wire accessories or longer mid-BW resistors (for solder-in probe heads) are used, they can be modeled by adding an RLC model in front of the appropriate probe head model and zeroing out the damping resistor in the probe head model. The schematics have parameterized R, L, and C values that are given in the SPICE deck for the probe head. Additionally, an input impedance plot is given that shows the matching of the measured data to the modeled data. Matching is generally very good up to the specified BW of the probe head with the 7GHz probe amp.

 

Input Impedance SPICE Models for InfiniiMax 4 Series RCRC Probe Heads

The spice model for the following probe heads are located in the MX0030A/31A/32A InfiniiMax 4 Series RCRC Probe Amplifiers & Probe Heads User’s Guide.

Sample top view of the MX0041A/42A Differential Solder-In Probe Head.

MX0041A/MX0042A Differential Solder-In

Input Impedance SPICE Models for InfiniiMax RC Probe Heads

The spice models for the following probe heads are located in the MX0023A InfiniiMax RC Probe Amplifier and Probe Heads User’s Guide.

 

Sample side view of the MX0100A Micro Probe Head.

MX0100A Micro Probe Head Kit

Sample top view of the MX0106A Differential Solder-In Probe Head.

MX0106A Differential Solder-in

Sample top view of the N2839A Differential Browser Probe Head.

N2839A Differential Browser

Sample of the MX0105A Differential SMA Probe Head.

MX0105A Differential SMA

Input Impedance SPICE Models for InfiniiMax III Probe Heads

The spice models for the following probe heads are located in the InfiniiMax III Series Probes User's Guide.

Sample of the N5439A InfiniiMax III ZIF Probe Head.

N5439A
ZIF Probe Head

Sample front view of the N2836A InfiniiMax III Solder-In Probe Head.

N2836A
Solder-In Probe Head

Sample front view of the MX0109A Extreme Temperature Solder-In Probe Head.

MX0109A
Extreme Temperature Solder-In Probe Head

Sample of the N5441A InfiniiMax III Solder-In Probe Head.

N5441A
Solder-In Probe Head

Sample of the N5444A InfiniiMax III SMA Probe Head.

 

N5444A
2.92 mm/3.5 mm/SMA
Probe Head

Sample side view of the N5445A InfiniiMax III Browser Probe Head.

N5445A
Differential
Browser Head

Input Impedance SPICE Models for InfiniiMax II Probe Heads

The spice models for the following probe heads are located in the 1168/9B-Series Differential and Single-Ended Probes User's Guide.

 

 

Sample side view of the MX0100A Micro Probe Head.

 

MX0100A
Micro
Probe Head

Sample of the N5381B Differential Solder-In Probe Head.

N5381B
Differential Solder-In
Probe Head

Sample top view of the N2839A Differential Browser Probe Head.

N2839A Differential Browser

Sample of the N5382A Differential Browser Probe Head with magnified inset detail view.

N5382A
Differential Browser
Probe Head

Sample top view of the N5425A/B Differential ZIF Probe Head connected to a circuit board.

N5425A
ZIF Probe Head

Sample side view close-up of the N5425A ZIF Probe Head with N5426A ZIF Tip attached.

N5425A ZIF Probe
Head with N5426A
ZIF Tip attached

Input Impedance SPICE Models for InfiniiMax I Probe Heads

The spice models for the following probe heads are located in the 1130B-Series Differential and Single-Ended Probes User's Guide.

Sample front view of the E2675B InfiniiMax Differential Browser Probe Head connected to a circuit board.

E2675B
Differential Browser Probe Head

Sample front view of the E2676B InfiniiMax Single-Ended Browser Probe Head connected to a circuit board.

E2676B Single-
Ended Active Browser
Probe Head

Sample front view of the E2677A/B InfiniiMax Differential Solder-In Probe Head connected to a circuit board.

E2677A
Differential
Solder-In Probe Head

Sample front view of the E2678B InfiniiMax Differential Socketed Probe Head connected to a circuit board.

E2678B
Differential Socket
Tip Probe Head

Sample front view of the E2679B InfiniiMax Single-Ended Solder-In Active Probe Head connected to a circuit board.

E2679B
Single-Ended Active
Solder-In Probe Head

Input Impedance SPICE Models for W2637A, W2638A, and W2639A Probes

The spice models for the following probes are located in the W2637A, W2638A, and W2639A User's Guide.

 

Sample top view of the W2637A LPDDR BGA Probe.

W2637A
LPDDR BGA Probes

Sample top view of the W2638A LPDDR BGA Probe.

W2638A
LPDDR BGA Probes

Sample top view of the W2639A LPDDR BGA Probe.

W2639A
LPDDR BGA Probes