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Hi!

This could just be me not knowing basic electronics, but I'm trying this circuit

and experiencing an issue. The output voltage of the op-amp (node Vout) is 0. The power voltage nodes make sense, as does Vo. Why is this, then? I thought this was a fairly typical dual-supply non-inverting gain circuit.

Thanks!

Jack

I didn't post twice, I don't know why it did that

The outpuy is at 0V because you have shorted the output of the opamp to ground!

:)

I am a super-noob but I had a vague notion that might be it haha. Success! Sorta. I need to read some stuff about electronics. Thanks!

New Question! If you check the circuit now,

I tried to add a second, similar op-amp with an inverted gain equation instead. (I also changed the resistor values for each, though the ratio should have remained the same.) However, now the gain on the first op-amp isn't what it should be (instead of 10 to 110 mv, it goes from 10 to 282), and I can't figure out why adding the new op-amp (or changing r-values) would mess it up like that. Any ideas?

Thanks!

Update. If anyone checks the little note I made on my circuit, the problem Only presents itself when the resistor values are both 10k. Even if the ratio stays the same, it's only when the total resistance gets up there that everything stops making sense. Is this a software thing?

Do both opamp outputs show the same apparent error or is it just the non-inverting stage?

What happens if you replace both opamps with the TL081 type?

I can't check at present as I have no access to a PC or iPad right now to run the sim.