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.

[moved] lm311 comparator with feedback

Status
Not open for further replies.

lukky61

Newbie level 4
Joined
May 5, 2015
Messages
6
Helped
0
Reputation
0
Reaction score
0
Trophy points
1
Activity points
33
Is feedback necessary in Lm311, what are advantages with feedback of positive or negative.
 

esp1

Advanced Member level 1
Joined
Sep 4, 2007
Messages
401
Helped
139
Reputation
278
Reaction score
139
Trophy points
1,323
Location
England
Activity points
3,372
hi,
I would always have some level of positive feedback when using the LM311 comparator.
This will prevent 'chatter' at the switching threshold. ie: rapid high/lows at the output at the threshold input switching level.

Never had an occasion to use negative feedback with a LM311.
E
 

crutschow

Advanced Member level 5
Joined
Feb 22, 2012
Messages
3,839
Helped
915
Reputation
1,828
Reaction score
899
Trophy points
1,393
Location
L.A. USA Zulu -8
Activity points
21,677
Comparators are not compensated for negative feedback so will likely oscillate if such feedback is attempted.
 

Audioguru

Advanced Member level 5
Joined
Jan 19, 2008
Messages
9,210
Helped
2,128
Reputation
4,250
Reaction score
1,955
Trophy points
1,393
Location
Toronto area of Canada
Activity points
57,857
There is an extremely low frequency amplifier circuit that uses a comparator with negative feedback as an opamp and it has frequency compensation with a fairly high value capacitor on its output to ground.
 

Attachments

  • comparator as an opamp.PNG
    comparator as an opamp.PNG
    11.8 KB · Views: 1

Status
Not open for further replies.

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Top