The circuit should have enough peak output current as it is.
There could also be stability problems with adding a buffer
in the feedback loop. Bear in mind that some op amps require
a minimum gain of five, and are not unity gain stable.
Your circuit needs the OPA627 instead, and looks like a misprint.
For some RIAA examples using buffers, see p. 6.11 here.
https://www.analog.com/media/en/training-seminars/design-handbooks/Op-Amp-Applications/Section6.pdf
There could also be stability problems with adding a buffer
in the feedback loop. Bear in mind that some op amps require
a minimum gain of five, and are not unity gain stable.
Your circuit needs the OPA627 instead, and looks like a misprint.
For some RIAA examples using buffers, see p. 6.11 here.
https://www.analog.com/media/en/training-seminars/design-handbooks/Op-Amp-Applications/Section6.pdf
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Hello
This circuit have a minimum gain of 1000, so the OPA637 would be stable in that circuit.
As any high speed op amp it need good decoupling capacitors very close to the op amp.
Thank
Bye
Gaetan
This circuit have a minimum gain of 1000, so the OPA637 would be stable in that circuit.
As any high speed op amp it need good decoupling capacitors very close to the op amp.
Thank
Bye
Gaetan
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I think you mean it places demands on the opamp's performance, yes that's true since the gain is high, leaving less open-loop-gain left to improve linearity compared to many use-cases for opamps.
Fortunately the RIAA gain is higher at low-frequencies, complementing the way open-loop gain rolls off at high frequencies.
No need to worry so long as the RIAA circuit doesn't try to have too much overall gain.