What shall we do with the Unused Op-Amp?

I was testing one of my projects and was annoyed by a lot of noise at the output on the last stage Op-Amp. What was wrong?

It turns out I let one op-amp (one half of a TL072) unconnected at all. This poor guy was completely unstable.

Check out the following articles on what to do with unused op-amps:

Below are the two recommended designs:


“A properly terminated uncommitted op amp. The input common-mode range is satisfied and the output is within the output voltage swing range.”>
“A properly terminated uncommitted op amp for prototype circuits. This termination scheme allows the op amp to be changed into an inverting or non-inverting configuration if the need arises in a later prototype stage.”>

1 Unfortunately, the original document is now gone. Archive.org has a partial copy. Some schematics and figures are missing. You can still view it here

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