I recently decided to use the MB102 Bread Board Power Supply module to power my op-amp in my circuit with the 5V power supplies. The schematics for this board is located here (http://digsys.upc.es/rpi/comp/PS_Schematic.pdf).

I need a positive and negative power supply for this op-amp and so I have tried to configure the positive terminal from the first power supply to the negative terminal of the second power supply. Thus the negative terminal of power supply 1 should give me -5V and positive terminal of power supply 2 should give me +5V. This method is currently not working for me and actually caused smoke to come from my first module. I was wondering why this is and if i'm doing something wrong.

I have done this method correctly using a regulated DC power supply and a separate arduino UNO R3 +5V with the same connection and it successfully powered my op-amp with no problem.


The MB-102 has a single 5 volt supply, with two output connections, and likewise a single 3.3 volt supply, with two output connections. The 5 volt and 3.3 volt supplies have a common ground connection. This can be easily seen by looking at the schematic diagram.

You cannot treat the outputs of this board as separate supplies, nor connect them in series to create a +/- 5 volt supply.

  • \$\begingroup\$ I see, so it's not possible to do so with the module but it is with the two seperate power supplies due to them not sharing a common ground connection? \$\endgroup\$ – hunter Palcich Apr 25 '17 at 5:43
  • \$\begingroup\$ It would as long as the supplies you drive them with are isolated from each other, i.e. two separate USB PSUs. You couldn't drive both modules from the same PSU as you would still have a common ground. \$\endgroup\$ – Finbarr Apr 25 '17 at 6:54

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