What happens when you flip the inputs of an op amp?

  • #76
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Well sure. The saturation points are there, but it doesn't change my question.
Abdullah A. - does that mean that you have the feeling that your question was not yet answered? (In spite of more than 70 contributions?)
 
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  • #77
Abdullah A. - does that mean that you have the feeling that your question was not yet answered? (In spite of more than 70 contributions?)
Oh my bad I was just working my way down the responses and I'm not even all the way through yet. But certainly my question has been answered a while back at this point! And with much gratitude for the amount of knowledge put in here beyond my expectations! I might even revisit this post after I've gone through more coursework and into the details of the internal circuitry of amplifiers and such to look at the responses from a new perspective once more.
 
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  • #78
Averagesupernova
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I really don't understand why this thread has the momentum that it seems to. Switching the inputs of an op-amp from inverting negative feedback to positive feedback as shown in the very first post of this thread does in no way imply that their analysis should be the same. If one cannot accept this from the beginning then one needs to be prepared for a difficult road ahead. That is not to say that I have not been fooled by some strange op-amp configurations. I certainly have.
 
  • #79
jim hardy
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I really don't understand why this thread has the momentum that it seems to.


upload_2019-2-8_12-27-34.png



For me it has been a months long search for that good sentence.
But it took @alan123 's picture in post 63 to unlock my alleged brain.

I think perhaps many of us people who are drawn to science struggle for words ? I know i do.
I struggle for math, too
best i can do for this circuit is

## Vout = 12 X \frac{(\frac{Vout}{2} + {Vin}) } {abs(\frac{Vout}{2} + {Vin}) } ##

....................

upload_2019-2-8_12-42-42.png


but i digress.... what counts is we got there. It took all of us, though.

Good thread !

old jim
 

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