Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronic 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.

Register Log in

differential apmplifier problem

Status
Not open for further replies.

jutek

Full Member level 4
Joined
Oct 21, 2005
Messages
211
Helped
6
Reputation
12
Reaction score
1
Trophy points
1,298
Activity points
3,140
hello

could you tell me what max gain i can achieve from circuit like this in the picture but with PMOS as the inputs and NMOS as a load?

i'm trying to simulate that with different currents and W/L ratios but the max i've achieved is 10V/V

What is incorrect? my expectations or calculations?

regards
 

nxing

Advanced Member level 1
Joined
May 10, 2004
Messages
422
Helped
24
Reputation
48
Reaction score
10
Trophy points
1,298
Location
China
Activity points
2,858
probably 10 is the correct number. the gain is Gm(nmos)/Gm(pmos).
 

beckchm

Banned
Joined
Nov 13, 2005
Messages
191
Helped
3
Reputation
6
Reaction score
1
Trophy points
1,298
Activity points
0
the gain is not big

because the output pmos is diode connect.

so the output resistance is small
 

jutek

Full Member level 4
Joined
Oct 21, 2005
Messages
211
Helped
6
Reputation
12
Reaction score
1
Trophy points
1,298
Activity points
3,140
nxing said:
probably 10 is the correct number. the gain is Gm(nmos)/Gm(pmos).
so, if i want to build 2 stage opamp i have to use another input stage to have much more gain?

regards
 

holddreams

Full Member level 6
Joined
Aug 2, 2005
Messages
351
Helped
15
Reputation
30
Reaction score
7
Trophy points
1,298
Location
Shanghai
Activity points
4,243
you can refer Allen's book ,chapter 6,Cmos operational amplifiers.
 

Status
Not open for further replies.
Toggle Sidebar

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Top