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I am reading the data sheet here http://www.ti.com/lit/ds/symlink/opa1664.pdf, and it says:

Wide Supply Range: of ±1.5 V to ±18 V, or +3 V to +36 V

Does that mean I can connect V+ to +5V and V- to ground of a typical 5V linear regulator?

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  • \$\begingroup\$ Yes it does. It supports dual or single supply. \$\endgroup\$
    – AngeloQ
    Apr 9 '17 at 0:08
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    \$\begingroup\$ Thank you for confirming that. Please post your answer, and if others will agree with you, I will accept it. \$\endgroup\$
    – darksky
    Apr 9 '17 at 0:09
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    \$\begingroup\$ But keep in mind that, if you use a single supply (say, 5 volts), you must reference any audio signals to about +2.5. In other words, you can't directly apply AC, such as audio, to the amp. Furthermore, the output will not drive a load which is grounded at one end to a negative voltage on the other. \$\endgroup\$ Apr 9 '17 at 0:14
  • \$\begingroup\$ Any power supply in the range of 3V to 36V can power the op amp. Regulation is not a power requirement, though it has benefits. \$\endgroup\$
    – Whit3rd
    Apr 9 '17 at 4:39
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Yes, you can, and the op-amp will be happy, however your circuit may not work unless you bias the inputs appropriately and take the output swing into account.

For example, the inputs must be maintained between 0.5 and 4V with a 5V supply at 25 degrees C (so narrower range over temperature) and the output cannot swing closer to the rails than 600mV (depending, again, on temperature and upon the loading of the output).

It could make sense to bias the inputs near the center of the input common mode range, which is 2.25V.

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  • \$\begingroup\$ ahhh, interesting! Obviously I want to avoid that, because the inputs are AC audio signals. So then I need two separate regulators? I wasn't able to find a single regulator that puts out +15 and -15. \$\endgroup\$
    – darksky
    Apr 9 '17 at 0:26
  • \$\begingroup\$ Typically one would use two regulators, one for each supply, however dual regulators do exist. They are not especially popular. \$\endgroup\$ Apr 9 '17 at 0:28
  • \$\begingroup\$ @darksky - You can always establish a reference point at ~2.25, then AC couple your audio into the op amp using a simple capacitor. \$\endgroup\$ Apr 9 '17 at 0:54
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    \$\begingroup\$ @WhatRoughBeast apparently that causes instability problems: analog.com/en/analog-dialogue/articles/… \$\endgroup\$
    – darksky
    Apr 9 '17 at 1:18
  • \$\begingroup\$ @darksky - only when driving high-current loads, which cause the power supply voltage to vary with signal. This problem goes way back, and in transistor (remember them?) amps it was called motor-boating - the oscillation caused a characteristic put-put sound. And the answer is given in the linked article - the reference 2.5 uses a bypass cap to decouple the ref from the supply voltage. \$\endgroup\$ Apr 9 '17 at 1:55
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Yes you can, this part supports single or dual supply. This assumes of course you aren't using it in a bipolar application. I.e. the output will of course not extend beyond the input voltage range.

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