An opamp question I can't make sense of

There is no feedback on the op-amp. The non-inverting input is higher than the inverting input so the output will be near the +ve supply, so about 12 V in this case.

Something wacky as well, The NI input is at 3V, the Inv at 2V, so
D is not 2V, its 1V. The inputs draw very small currents, on the
order of 80 nA. So drop across R's negligible.

Diver300 is correct as the differential input of 1V is amped by the Aol
of the OpAmp, so its close to its + rail because of no FDBK. The Aol
typically 200,000. The output V swing is ~ 1V off its supply rail, so
Vout ~ 13V.


Regards, Dana.

circuit975 said:

Greetings to everyone,

I found all values in an opamp question, but I couldn't find the Vout output value. How do we do the formulation?
I mean, with which formula will we calculate vout?


View attachment 146364

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What was the actual question?

atferrari said:

What was the actual question?

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The lines with the question marks is my best guess

circuit975 said:

How do we do the formulation?
I mean, with which formula will we calculate vout?

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The OP is from Australia - the "make"/"do" is a generic placeholder for the specific verb most other regions would use. I'm assuming the OP is under 25. Older Australians start to use specific verbs.

Common sense tells me if pin 3 Vin+ = 3V and pin 2, Vin- = 2V than as a comparator, the output will be towards Vcc = 14V

circuit975 said:

I mean, with which formula will we calculate vout?

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There is no "formula".
That question indicates you don't know how an op amp works.
Basically it's a differential amplifier with a very high differential gain (upwards of 100,000), so what would you think the output is for the differential input voltage you calculated?