I want to have a higher current output than most op amps (2A) and found the schematic below. But I want to control the output voltage. Could I use a divider circuit with two resistors in the feedback loop to do that?

Amplified op amp with feedback without resistors

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    \$\begingroup\$ What do you mean by "control the output voltage"? This circuit controls the output voltage, so how do you want it to be different? Please draw a schematic of how you want to add a voltage divider. \$\endgroup\$ – Elliot Alderson Sep 20 '18 at 21:15
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    \$\begingroup\$ Do you mean a pair of resistors like \$R_1\$ and \$R_2\$ in the circuit in this question (to provide amplification instead of merely buffering the input voltage)? \$\endgroup\$ – Null Sep 20 '18 at 21:18

You are controlling the voltage. You're controlling it to be the same as the input voltage over the range of about +/-4.3V.

If you want the full +/-5V range, you'll have to run the op amp from slightly higher rails due to the B-E drop.

If you want the output lower than the input, put a voltage divider to ground between the input signal and the positive input of the op amp.

If you want the output higher than the input, put a voltage divider to ground between the output and the negative input of the op amp.

If none of these guesses correspond to what you want, you'll have to clarify further.


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