High Incremental Drain impedance (from the book The art of electronics)

[khatus]

Hello guys, I don't understand the meaning of this line

"The FET has a high incremental drain impedance, giving roughly constant current for VDS greater than a volt or two"

from field-effect transistors chapter of the book "The art of electronics".
Here what does it means by "high incremental drain impedance" Can anyone help me to understand it?

 

[danadak]

See here - https://www.edaboard.com/threads/hi...k-the-art-of-electronics.412857/#post-1783070

Regards, Dana.

 

[bertus]

Hello,

And here:

High Incremental Drain impedance (from the book The art of electronics)

Hello guys, I don't understand the meaning of this line "The FET has a high incremental drain impedance, giving roughly constant current for VDS greater than a volt or two" from field-effect transistors chapter of the book "The art of electronics". Here what does it means by "high incremental...

forum.allaboutcircuits.com

Bertus

 

[Harald Kapp]

resistance: [imath]R = \frac {V}{I}[/imath] -> absolute values are used
incremental or differential resistance: [imath]R_{inc} = \frac{dV} {dI}[/imath] -> differential values are used

For a "normal" resistor [imath]R = R_{inc}[/imath].
For a nonlinear component [imath]R \neq R_{inc}[/imath].

The references given in the other answers give more detailed explanation.