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.

[SOLVED] question about gm vs gm/Id if L increases

Status
Not open for further replies.

melkord

Full Member level 3
Full Member level 3
Joined
May 18, 2018
Messages
151
Helped
0
Reputation
0
Reaction score
1
Trophy points
18
Activity points
1,772
I characteritzed my device and got the result like the picture below.
Here I also copy some text from the book by Binkley.
In Chapter 4, the book said that if L increases, gm nearly unchanges.
in CHapter 5, it is said that low IC and long channel lengths maximizes gm.

I think it is contradictive with the result I got.
I really appreciate it if someone can shed some light here.

1609380005535.png
 

You are probably not doing this simulation with a fixed inversion coefficient. If you change L, you must change W accordingly so as to keep a constant IC (assuming a fixed drain current). This way both gm and gm/id should not change too much with L.
 
You are probably not doing this simulation with a fixed inversion coefficient. If you change L, you must change W accordingly so as to keep a constant IC (assuming a fixed drain current). This way both gm and gm/id should not change too much with L.

Thank you.
Yes, you are right.
Actually I use gm/Id method to characterize my device, not this IC method introduced in the book.
I use the book to study the optimization.
 

Status
Not open for further replies.

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Back
Top