Question about the Native Mosfet

[jiangnancai]

why native nmosfet

1.Is the model of Native Mosfet has same accurancy as nominal Mosfet?
2.Who had used the native Mosfet in real design? any special considerations?

thx!:|

 

[frankliner]

1. Yes.
2. Matching is not as good as an enhancement type transistors. I've seen start-up problems due to people assuming vth<0. At -40 the this may not be true.

 

[dick_freebird]

Accuracy comes down to cases. The "native" or "intrinsic"
FET may not be as well modeled as main NMOS types,
or may have added nonidealities (e.g. more / sooner
rollon of leakage w/ Vds, elevated and variable non-
gate-controlled leakage floor, etc. It's up to the foundry
how well they model and control it. My experience is
with thin film SOI devices but I agree that generally
the process and mismatch variabilities are greater.

That said, I have used them many times in analog
circuits with good results, and my company uses them
in many high-volume RF products.