Why doesn't this opamp circuit work?

Question

I did a standard inverting operational amplifier (UA741), with Rin = 6k and Rf = 1k.

I have a lab power supply, with 30V of difference for the amplifier.
I don't understand why this doesn't work, it should be Vout = -Vin/6 but I measure Vin = Vout = V-(AO).
I put Vin between 0 and 10V for instance, static, and voltage measurements are made with a standard voltmeter. I tried with several new op amps and it's the same problem.

Spehro Pefhany · Answer

You can't just put a 30V power supply on the op-amp, you need a ground so that you have something like +/-15V.
If your lab supply does not share a ground with your signal source you can create a pseudo ground at DC by doing something like this:

simulate this circuit &ndash; Schematic created using CircuitLab

Andy aka · Answer

It's an inverting amplifier hence with Vin at some positive value, Vout has to be a negative value but, you don't have a negative supply rail on pin 4 hence it won't work because the output cannot become a negative value.

Answered by Andy aka on December 29, 2021

Why doesn't this opamp circuit work?

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