Continue to Site

Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

Triode region of NMOS transistor

Status
Not open for further replies.

sungyueh

Newbie level 1
Joined
Feb 20, 2004
Messages
1
Helped
0
Reputation
0
Reaction score
0
Trophy points
1,281
Activity points
10
deep triode subthreshold

Hi,

Is it true that a NMOS is easier kept in the triode region if its W/L ratio it larger?

Thanks.
 

easier kept on subthreshold region......current density will be very low...

Amit
 

To keep any trnaistor in triode region, Vds must be smaller than the saturation voltage defined as Vdssat=2/(n*gm/Id), where n is the inverse of the subthreshold slope.

For a given Id, as W/L increrases, gm/Id does it too and then Vdssat decreases. In the limit (very deep) of subthreshold conduction, Vdssat saturates to about 3-4Vt, where Vt is kT/q.
 

you can use the triode region of the MOS as controllable conductance. Works great for transconductance stages with ground refered input voltage. If L get longer the linearity improves. For most techs 4*Lmin works.
 

rfsystem said:
you can use the triode region of the MOS as controllable conductance. Works great for transconductance stages with ground refered input voltage. If L get longer the linearity improves. For most techs 4*Lmin works.
why L get large, the linearity improves? Thank you!
 

shanmei said:
rfsystem said:
you can use the triode region of the MOS as controllable conductance. Works great for transconductance stages with ground refered input voltage. If L get longer the linearity improves. For most techs 4*Lmin works.
why L get large, the linearity improves? Thank you!

channel length modulation has less impact?
 

HI
Vds<Vgs-Vt to maintain a transistor in linear region.W/L also effect current flow .
 

Status
Not open for further replies.

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Back
Top