Hi! I’m working on an arduino project that has a -12v/0v/+12 psu. +12 is fed directly into arduinos voltage regulator, so there’s also a +5v line available. I need to convert a -5v+5v signal to 0v+5v to feed it into arduinos analogue input and I’ve already mocked up a schematic in circuitjs based on an opamp that seems to do what I want. The only problem is that it needs -5v to shift the signal to be unipolar. I know that I can invert +5v using another opamp, but maybe there’s some simpler way? I’d really like to avoid adding another opamp just for this? In this schematic I used simple voltage divider to get the needed voltage, but I guess that’s not the best approach?

TLDR: I have -12v, 0v, +12v and +5v, what’s the easiest way to get -5v?

2 points

Oops, the schematics didn’t attach for some reason, let’s try to add it here

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Supply the OpAmp with +/-12V or +5/0V and use a non inverting Summing OpAmp Circuit to get your 0-5V signal. V1 is 5V, V2 your input.

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thanks! gonna give it a try tomorrow. I’m pretty new to this, and never used opAmps in non-inverting configuration, so I missed this option

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Exiting! It has been some time for me too, let me know how you solved the problem at the end.

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it worked! (at least in the sim)
thanks a lot!
I’m not sure I got all the math right, since I get 0 - 5.05V on the output, but it’s not a deal breaker for me.
I attached the schematics, but not sure that images in comments federate from kbin to lemmy, so if you don’t see it, try opening an original link to this comment.

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