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Intrinsic Gate resistance of FQP9N90C MOSFET?
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ogden:

--- Quote from: T3sl4co1l on October 09, 2018, 01:04:39 pm ---As crude as can be, avalanche pulse generator (waveform into 50 ohms shown as Ref), BNC tee to binding posts and scope; binding posts to twisted pair up to gate.  Waveforms are interpolated from a 10GS/s acquisition (equivalent time sampled, 350MHz BW).

--- End quote ---

Wow, nice. I was aware of TDR impedance measurements, but did not consider such as practical. Thank you for info!
T3sl4co1l:
The important thing here is, it seems to fit well, without having a distributed RC characteristic (which would be represented by multiple R+C in parallel, of geometrically spaced R and C values).

Testing, I find 3.279 mV RMS error with an RC, and 3.278 with an (R1+C1) || (R2+C2) network (R1 = 1.337, R2 = 10.09, C1 = 2.088, C2 = 1.162).  The captured waveform is 40ns long, so both time constants (2.8ns, 11.7ns) are significant and accounted for.

Not finding any success with a couple of tweaks to try and reproduce the high frequency ringing.  It should only be an artifact of my setup, anyway.

Tim
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