I am trying to make a simple non inverting amplifier using an LM358P.

I have run into a problem: the output voltage is 0. I have tried both amplifiers on the chip.

I have listed the pin configuration below:

Pin 8: Positive input of 5.8 V
Pin 4: Negative input of 5.8 V
Pin 3: Positive input of 1.8 V, negative to -ve rail on breadboard.
Pin 2: Resistor 1 to ground
Pin 2: Resistor 2 to pin 1 (output)
Pin 1: Voltage out

The voltage output is 0, measuring from pin 1 to -ve rail.

What am I doing wrong?

Circuit Lab

Bread board

  • 4
    \$\begingroup\$ Please provide a schematic diagram. You may use the CicuitLab tool on the toolbar of the question editor. Please also post a photo of your breadboard layout \$\endgroup\$
    – RussellH
    Commented Feb 17 at 20:02
  • \$\begingroup\$ Resistor 2 to pin 1(Output), not pin 3 \$\endgroup\$
    – Jens
    Commented Feb 17 at 21:08
  • 1
    \$\begingroup\$ How are the power supplies arranged? Is the measured voltage having a common ground reference with the op-amp supplies? \$\endgroup\$
    – Justme
    Commented Feb 17 at 23:20
  • \$\begingroup\$ Different ground. \$\endgroup\$ Commented Feb 17 at 23:36

1 Answer 1


It does not work if supplies have no common ground reference with the voltage you want to measure.

So what you built does not match the schematic that was drawn.


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