Can I Power a Single Supply Op Amp (LM358) with a Dual Power Supply (two 9V batteries for example)?

Question

Hello, I am making an EEG circuit powered by two 9V Batteries. I intended on using multiple LM358 op amps in this circuit, but the LM358 does not have a -Vcc pin since it is a single supply op amp. Instead it has a GND pin instead (refer to pinout picture provided (on the left)).

In order to use two 9V batteries with the LM358, would I be able to connect the negative terminal of one of the 9V batteries to the GND pin of the LM358 and the positive terminal of the other 9V battery to +Vcc?

If not what dual supply op amps will work for two 9V batteries? For instance, could a LF411 or LM741 do the job?

I am a novice in circuitry so I appreciate any input, thanks.

Answer 1

From the data sheet:



Wide Power Supply Range:

– Single Supply: 3V to 32V

– Or Dual Supplies: ±1.5V to ±16V

Answer 2

Have you bothered looking at the data sheet for an LM358? That's where you start. And you can look at power supply voltages.



Simple.



http://www.ti.com/product/LM358

Answer 3

"single supply op-Amp" means the input common mode range includes the negative rail. This is similar to what today you will hear called rail-to-rail input, which also operates at the positive rail. While handy, a good circuit design avoids the need for either, since there are other performance repercussions.

Answer 4

You could power with two batteries in a dual-supply config, but that's not what I'd do.



See if you can find a friend who knows electronics to help you. I would use a single battery, and use a high-impedance resistive divider to create a virtual ground at 4.5 volts. Put ceramic capacitors between that virtual ground and the battery + and -. Then use your circuit as designed. Your friend can explain what I just said, if it doesn't make sense, and can also adapt the circuit to single supply if that's needed. EEG is a low-signal measurement, so shielding and layout may be important.

Answer 5

yes, you can, as the other answers detail.



edit: but if your input voltage range can only vary from slightly negative to +7, you can run them off one 9v battery.

Answer 6

TREAT THE - Vcc AS THE GND SHALL DO.