Can 3V NMOS work under 5V supply voltage? how?

[hsiangleung]

I need a medium threshold NMOS in my design,but there is no accessible 5V mvt NMOS in my process. So I have to use the 3V mvt NMOS. But in my design, its gate is connected to the 5V supply voltage. Will this be a problem? If does, how can I fix it. Any suggestion? Thanks!

 

[yassin.kraouch]

I need a medium threshold NMOS in my design,but there is no accessible 5V mvt NMOS in my process. So I have to use the 3V mvt NMOS. But in my design, its gate is connected to the 5V supply voltage. Will this be a problem? If does, how can I fix it. Any suggestion? Thanks!

what is the NMOS part number ? or you can share the datsheet,

 

[Dominik Przyborowski]

What kind of circuit is it? It is possible to use std devices with higher supply voltage but with some conditions. The gate to source/drain voltage shouldn't exceed technology nominal supply (gate oxide thicknes is in order of a few nm so too high voltage drop causing breakdown), also very high Vgs and Vds could produces high lateral abd vertical electric fields seriously deteriorating electrical parameters of transistor.

You didn't mentioned which process are You using, but threshold voltage are a function of transistor length and could differ by 50% between short and long channel devices.

Check this article or this book