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MIC923 opamp as voltage follower

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Endre

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Hello,

The datasheet of the opamp writes this:
The MIC923 requires a minimum gain of +2 or –1 but is stable
driving any capacitive load.

Does it mean that this opamp cannot be used as a voltage follower (gain=1)?

Later the datasheet says:
To use the part as a follower, the output should be connected to input
via a short wire.

Isn't this citation in contradiction with the first one?
 

We require to read the full datasheet to understand the apparent contradiction.

Phrases taken out of context can sound contradictory. But after reading the complete explanation, there may be a exceptions of circumstances which clarify the issue.
 

Yes, that means the op amp will be unstable if used as a +1 follower.

A minimum closed-loop gain of +2 for a non-inverting amp or a gain of -1 for an inverting amp is the same from a loop-gain point of view since in each case you have two equal value resistors going to the op amp (-) input.
The only difference between the two configurations is the swapping of the input signal and ground.
From an AC feedback point of view the two configurations are the same.
Thus there's no contradiction in those two requirements.
 
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    Endre

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I missed your reference to the contradiction.
Yes, the comment about using a short wire would seem to contradict the fact that it won't be stable as a follower.
Must have been a cut and paste error from another data sheet.
 
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