Transistor - 3 - MOS Transistor Current Expression

Transistor - 3 - MOS Transistor Current Expression

[@user-nt8le5yp8i]

Sir, Why the surface charges (we are using Phis potential) are not participating in conduction, they are also free charges on surface right ?

[@Awakened_Pot]

They are not mobile.

[@bharadwaj767]

23::07_07-04-24_@IIIT_H how Vd effects voltage at MOS_Cap (surface inversion layer) --> what if Vd>Vg-Vth...? inversion (e^-)charge decreases : Pinch-Off

[@chetanggs]

Why was there a minus sign at 6:52 ,when in previous video that equation was positive

[@who.abhinav]

Because in inversion region free electrons are present. If we are considering immobile ions then there would have been a positive sign.

[@ajiths1689]

can i get the slides presented in the lectures anywhere?

[@faneeshbansal]

yes, it is there on the nptel website.

[@hummock3983]

@ 5:56 how did he write Q'I here? complete explanation, please.

[@akashekhar]

From previous lecture, we know Qi' = - Cox (Vg - Vt). Here, an extra term (-V = - V(x)) comes because as we are applying the Vd at one end, it will create a voltage gradient along the channel length called V(x) for an element length 'dx', which will oppose the voltage applied at Vg.