Mosfet caracteristics for a gyrator

Hello. I want to build a gyrator inductor to replace a 30h 100mA.
I would like better performance if possible, so I used LTspice sim (new to this).

And I found that different mosfet give different attenuation at 120Hz



So what should I look for when choosing a mosfet for a gyrator. I have not found anything on the internet.


Thank you.
 
Last edited:

Elvee

Member
2006-09-08 2:04 pm
Once you have sorted out basic, down to earth parameters like Id max, Vto, Pd max, etc, the most important parameter for static performance is lambda (channel modulation):

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It will determine the ultimate low frequency performance possible for a simple (no global FB) gyrator.


If you are interested in HF rejection too, capacitance could also be important.

The λ is not specified in the datasheet, only in the spice model (not always).

If the DS has the full set of Id/Vds curves, it can be estimated from the slope of the curves (deviation from horizontality)
 

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