benchen
Member level 2
There are two type of nmos in TSMC 0.18um 1.8Vdd. one is norminal Vt and the other is medium Vt.
When I use norminal Vt nmos, I found when nmos is diode connected, its Vgs is even smaller than Vth and in region 3. Why? Usually in this case the nmos is in saturation region and Vgs is larger than Vth.
What is the difference between these two nmos besides the different Vth value?
For analog design, which nmos should we choose?
Thanks!
When I use norminal Vt nmos, I found when nmos is diode connected, its Vgs is even smaller than Vth and in region 3. Why? Usually in this case the nmos is in saturation region and Vgs is larger than Vth.
What is the difference between these two nmos besides the different Vth value?
For analog design, which nmos should we choose?
Thanks!