1. I would like to power a a TL072 opamp which is a rail to rail (+15/-15 volts)
2. I don't know about the current output/input
3. I'm using the TL072 for a wein-bridge oscillator as shown in the attachment.
Question: How to get the +15 and -15 volts from the 9 volt batteries (plural)?
You can't unless you use switching regulators to change the voltage.
But the circuit should work fine with two 9V batteries in series, one for the plus voltage and one for the minus voltage. The junction of the two batteries in series goes to circuit common. The maximum output voltage will be reduced, of course, but otherwise there should be little difference in the circuit's operation.
You could do that; but then you'd need another 2 batteries and a 15V -ve regulator as well to get -15V.
Why not just use +9/-9V as suggested in post #2?
You could do that; but then you'd need another 2 batteries and a 15V -ve regulator as well to get -15V.
Why not just use +9/-9V as suggested in post #2?