IDEAL I-V CHARACTERISTICS
1. MOS I-V characteristics
· If Vgd < Vt, channel pinches off near drain
· When Vds > Vdsat = Vgs – Vt
· Now drain voltage no longer increases current
2. Threshold voltage
From equation, threshold voltage may be varied by changing:
· The doping concentration(NA)
· The oxide capacitance(cox )
· Surface state charge(Qfc )
