I purchased a DIY op-amp kit from eBay. The parts arrived in a baggy, I soldered it all together, but have no idea how to wire the power supply?

I am hoping to use 9V batteries, and realize I might have to run two or more in series? I am pretty new to this electronics thing.

What is confusing me is that the hookup has "VDD", "-GRD-", and "-VCC". I have no idea what connects to what in terms of batteries, etc.

I have attached several photos with the amp, chips, etc. It did not come with instructions, datasheets, etc.

Circuit Board

Power Hookup


  • \$\begingroup\$ Thank you for all the photos, but it would help a lot more if we could look at the schematic. \$\endgroup\$
    – Oldfart
    Mar 29, 2020 at 20:47
  • \$\begingroup\$ I don't have one. It came in a baggy, no instructions, no datasheets, nothing. Sorry. \$\endgroup\$
    – Hunter
    Mar 29, 2020 at 20:49
  • 1
    \$\begingroup\$ We need a schematic to be able to say anything useful about this circuit. You have the PCB so you can reverse engineer the schematic from that. Did you look on the website printed on the PCB? Probably you need a symmetrical supply like + 9 V and - 9V. Probably the module will work of you apply + 9V to VDD and - 9 V to VCC but anyone why marks supplies like that has no clue, this doesn't follow normal conventions (VDD and VCC are both for positive voltages, VSS and VEE are for negative rails). \$\endgroup\$ Mar 29, 2020 at 20:51
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    \$\begingroup\$ In that case I suggest you trace the connections and reverse engineer the board. Otherwise it is not much use to you and you will not understand how it works and you will not learn anything from it either. \$\endgroup\$
    – Oldfart
    Mar 29, 2020 at 20:52
  • \$\begingroup\$ You could try: VDD + (9V battery) - GND - + (9 V battery) - VCC But no guarantees if this is wrong your opamp might be damaged. Only a schematic will tell me if what I propose is OK or not. Next time: buy a kit with a schematic. For an experienced EEs this is easy, we just measure where the supply pins of the NE5532 go. But for a beginner, you need a schematic. \$\endgroup\$ Mar 29, 2020 at 20:53

1 Answer 1


I am hoping to use 9V batteries, and realize I might have to run two or more in series?

This is how to make bipolar power supply using two batteries.

enter image description here

And for reverse engineering the board - check to which connector terminals goes pin4 and pin8 of the IC. Then connect batteries correspondingly +Vs to Vcc+, -Vs to Vcc- and GND to GND.

enter image description here

Image taken from Datasheet.


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