Relation between closed loop and open loop gain of an opamp

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The_pearl

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Hi,
Does the closed loop gain have an impact on the open loop gain of an opamp in feedback configuration I'm aware of the Aol/(1+βAol) equation but I wonder if a higher closed loop gain would affect the open loop gain? Also does the phase margin vary with closed loop gain possibly causing instability and resulting in lower open loop gain? If yes, an intuitive explanation would be helpful.

Thank you for your time.
 

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No, the closed-loop gain has little effect on the open-loop gain, which is determined by the internal circuit configuration of the op amp.

The phase margin will vary with the closed loop gain, and is usually the worst at a closed-loop gain of one.
 

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    The_pearl

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There is a general consensus that “open-loop gain Aol” refers to the gain of the amplifier unit without a feedback network.
Therefore, the “closed-loop gain Acl” is, of course, dependent on Aol (but not vice versa).

In contrast to this, we define the loop gain (product of Aol and the feedback factor β), which is particularly important for stability studies.
 

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