i had to do a study using a summing amplifier to see if the results i got agreed with theory, the answers i got was something like 9.62, the answer i should of got was 10, now this doesnt seem that far away, BUT the errors didnt agree at all, they only agreed within 4 standard errors, so i was looking for a reason why they may not have agreed.(adsbygoogle = window.adsbygoogle || []).push({});

My orginial thought was that:

The summing amplifiers summing equation made an assumption that the current inside of the op am was 0 and as a result wud overestimate the summed voltage.

I spoke to my instructer and he said it would be negligable.

So i dont really have a reason why

The theory equation is

[tex]Vout = -(\frac{Rf}{R1}V1 + \frac{Rf}{R2}V2)[/tex]

the measured value i get is -(9.620±0.005)V

the expected value i get is -(10.00±0.01)V

as you can see they only agree within 4 standard errors of each other.

Im a bit stumped at a reason why

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# Homework Help: Summing amplifier results dont agree with theory

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