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.

op-amp with gain>60db

Status
Not open for further replies.

elmasso

Newbie level 1
Joined
Mar 6, 2014
Messages
1
Helped
0
Reputation
0
Reaction score
0
Trophy points
1
Activity points
13
hi i have a homework that want me to design a op-amp with these specs :

single ended output and gain greater than 60db
capacitor load 1pf
Vdd = 3.3v
output swing > 2.4v
ugf>200MHz
Slew Rate > 400v/us
power<6mW
phase margin >60 degrees

it would be great help if someone can help me with design or introduce me some sources ASAP
 

erikl

Super Moderator
Staff member
Joined
Sep 9, 2008
Messages
8,112
Helped
2,694
Reputation
5,368
Reaction score
2,293
Trophy points
1,393
Location
Germany
Activity points
44,054
... introduce me some sources

I think it's not impossible, but challenging. You'll need at least 400µA in the output stage(s).

Read chap. 5: Design of CMOS Operational Transconductance Amplifiers Optimized for DC, Balanced, and AC Performance from David M. Binkley's book "Tradeoffs and Optimization in Analog CMOS Design"
 

tompham

Full Member level 2
Joined
May 29, 2010
Messages
133
Helped
29
Reputation
60
Reaction score
29
Trophy points
1,308
Location
usa
Activity points
2,066
Hi elmasso

Use folded cascode with tail current and 2 legs > 400uA you can do it
 

schmitt trigger

Advanced Member level 5
Joined
Apr 17, 2013
Messages
2,727
Helped
859
Reputation
1,722
Reaction score
847
Trophy points
1,393
Activity points
18,440
The question is: is the 1pF load realistic at all?
This is way too low. Almost anything that you put on the output will have at least a few pF.
 

schmitt trigger

Advanced Member level 5
Joined
Apr 17, 2013
Messages
2,727
Helped
859
Reputation
1,722
Reaction score
847
Trophy points
1,393
Activity points
18,440
Not, if it is a CMOS gate again, e.g. an output amplifier on the same chip.

You are absolutely correct,
but unfortunately the poster's original requirements left this open to interpretation.
 

Status
Not open for further replies.

Similar threads

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Top