- #1
samski
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everyone loves these things but i can't get my head around it... any explanations seem to go from blindingly simple to technical very quickly... i understand logic comparators but as soon as negative feedback is included i get all confuzzled.
OK so i understand that the output will become G((V+)-(V-)). So if you use 100% negative feedback, i don't undertand why you will get the same output out as you put in... this is what i am referring to - http://web.telia.com/~u85920178/begin/opamp00.htm in the first part of the section "The Op-Amp As A Comparator - Analogue"
it says: "The only stable condition that can exist is if the + and - inputs are the same voltage."
however i was under the impression that if the + and - input are the same, the output is 0v because G*(x-x)=G*0=0. therefore this wouldn't be a stable input...
im also quite confused about limiting gain by using resistors and things but i guess ill understand that if i understand the basics...
i hope somebody can help...
thanks!
sam
OK so i understand that the output will become G((V+)-(V-)). So if you use 100% negative feedback, i don't undertand why you will get the same output out as you put in... this is what i am referring to - http://web.telia.com/~u85920178/begin/opamp00.htm in the first part of the section "The Op-Amp As A Comparator - Analogue"
it says: "The only stable condition that can exist is if the + and - inputs are the same voltage."
however i was under the impression that if the + and - input are the same, the output is 0v because G*(x-x)=G*0=0. therefore this wouldn't be a stable input...
im also quite confused about limiting gain by using resistors and things but i guess ill understand that if i understand the basics...
i hope somebody can help...
thanks!
sam
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