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Modeling >> Passive Devices >> Microprobe needle equivalent circuit?
https://designers-guide.org/forum/YaBB.pl?num=1332429765

Message started by SoliS on Mar 22^nd, 2012, 8:22am

Title: Microprobe needle equivalent circuit?
Post by SoliS on Mar 22^nd, 2012, 8:22am

I know this is EXTREMELY variable and depends on needle pressure, metal pad size, condition of the needle tip, type of probe, etc.

But, is there some sort of approximate schematic that represents some of the major parasitics that come from landing a simple microprober needle (not even coax or triax or GSG, just a DC needle)? Google is not much use here.

There will be contact resistance, some sort of series inductance, and probably fringing capacitance. Anybody have a decent order-of-magnitude feel for this sort of thing?