Trying to figure out the formula for this op am circuit

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icemetal

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Trying to figure out the formula for this op-amp circuit

I been trying to figure out the formula for this circuit but I could not find anything similar online the output is an average of 3 V but I want to understand why, and whats the formula for it.



 

I think you drew the circuit wrong. As it is, the output is +5V.

The opamp is connected as a unity gain buffer, so output voltage is the same as the input at pin 5, which is connected to +5V through R3.
 

Nope, there's a direct connection from +5V to R3.

Some current will flow from +5V to -2V through R1, and from +5V to ground through R2, but none of that affects the voltage on R3.
 

thanks, but are ignoring all the resistor values and the negative input voltage, so your answer is not correct, if you dont believe me just build that circuit with the resistors and you would see.
I feel good that I'm not the only one who does not know the formula, it is a bit complicated with the negative voltage, the op-amp I can see is just a buffer. but how does resistor and the negative voltage affect the value?
 

Seriously, if you're getting 3V at the output, then the circuit you built isn't the same as the one in the diagram. Can you double-check it?
 

I agree with godfreyl. The diagram shows 5V connected directly to R3, so R1 and R2 have no affect on the voltage (assuming ideal components). Thus the output voltage should be 5V. No Ohm's law needed.
 
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