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# OPAMP as a subtract or and amplifier

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Can I use OPAMP as a subtract or and amplifier both insingle IC.

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"subtract or and amplifier" means what? Or is it a typo?

I am getting signal from 2.54 VDC to 4.5 VDC, I want to convert is from 0 VDC to 10 VDC.

Hi.

Not sure, don't know much about op amps but sounds perhaps unlikely using only a single IC if what you mean is one device that can both add and subtract, maybe one exists, it sounds more like what I think is called a full adder, which isn't an op amp, and I imagine they are logic level input/output anyway.

If you mean something that the input ranges from 2.54 - 4.5VDC and the output is 0 - 10VDC, then at a guess, yes (but I don't think you'd get a variable output voltage), from the little I know, you'd set the input reference, and that sounds like a comparator.

https://www.electronics-tutorials.ws/opamp/op-amp-building-blocks.html

You can do it pretty easily with a differential amplifier.

The input voltage range is 2.54v to 4.5v, an input change of 1.96 volts.
We are trying to get a 10 volt output change.

So the required amplifier gain is 10/1.96 or x5.102

A 10k resistor and a 51k resistor combination comes pretty close to giving the required gain.

The +ve input to the differential amplifier will be our 2.54v to 4.5v input signal.

The -ve input to the differential amplifier should be from a constant +2.54 voltage reference source.

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d123

### d123

Points: 2
Below is a simulation of the circuit.
I changed the value of R2 to get the output nominal voltage close to the desired value with the Pot at the middle of its adjustment range.

d123

Points: 2