Feedback


I read this and found it interesting. Thought it might generate some interesting discussion here. 
https://www.audioholics.com/audio-amplifier/amplifier-negative-feedback
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Showing 2 responses by almarg

Great posts above; thanks to all.

Ralph (@atmasphere), what do you think of Mr. Putzeys’ statement that ...

... the idea that feedback causes TIM is probably most noteworthy for being not just wrong, but also the exact opposite of the truth. TIM happens in the input stage. An increase in global feedback makes the input stage work less hard. That causes a disproportional reduction in TIM.

Thanks. Best regards,
-- Al

Thanks, Ralph ( @atmasphere ). So would it be fair to say that feedback can cause TIM if the amount of feedback that is applied is insufficient to prevent it, but in many designs it is not practical to apply that much feedback "due to all the frequency poles which limit phase margin and decrease Gain Bandwidth Product." (Quoting from one of your earlier posts).

If so, I believe that would reconcile Mr. Putzeys' statement with the seminal work of Dr. Matti Otala, mainly in the 1970s, that was referred to by @tomic601 in an earlier post. 

Thanks! Best regards,
-- Al