Measure JFET drain current with a current mirror

RE: Measure JFET drain current with a current mirror

Jan Cumps — Tue, 08 Sep 2020 19:26:01 GMT

The current mirror (and familiar differential input amp) is covered in Art of Electronics a few times

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RE: Measure JFET drain current with a current mirror

jc2048 — Mon, 29 Jun 2020 07:32:51 GMT

Is there a reason for not doing the measurement of Vds directly?

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RE: Measure JFET drain current with a current mirror

Jan Cumps — Sun, 28 Jun 2020 09:45:36 GMT

Here's an animation of captures with different gate voltage:

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RE: Measure JFET drain current with a current mirror

jw0752 — Fri, 26 Jun 2020 20:47:41 GMT

Thank you for the interesting technique.

John

RE: Measure JFET drain current with a current mirror

DAB — Fri, 26 Jun 2020 18:26:22 GMT

Very good post Jan.

Very interesting.

I had not looked this deep into the JFET.

DAB

RE: Measure JFET drain current with a current mirror

genebren — Fri, 26 Jun 2020 16:37:42 GMT

Very cool! Thanks for sharing (yours and the original).