1
\$\begingroup\$

As you all know, most Inst. Amp. examples on the Internet have a 'Differential Amplifier' part as shown below.

But, what would happen if a summing amplifier was used instead ? What kind of disadvantages I would have ?

Noise elimination and gain are very similar like Diff. Amp. does if my calculations are correct.

Any comment will be appreciated. Thank you for your consideration.

enter image description here

\$\endgroup\$
3
  • 1
    \$\begingroup\$ Um.. you would end up cancelling out your differential signal and amplifying the common mode noise instead... \$\endgroup\$
    – Trevor_G
    Commented Oct 12, 2017 at 15:26
  • \$\begingroup\$ I think you need to look up the core reasoning in using a differential amplifier (differential mode amplification, common-mode rejection) \$\endgroup\$
    – Joren Vaes
    Commented Oct 12, 2017 at 15:29
  • \$\begingroup\$ "... if my calculations are correct." Let's see the calculations! See my answer to electronics.stackexchange.com/questions/332390/… which may help. \$\endgroup\$
    – Transistor
    Commented Oct 12, 2017 at 19:33

1 Answer 1

Reset to default
1
\$\begingroup\$

With a differential amplifier you are removing the noise and amplifying the signal. With a summing amplifier you are removing the signal and amplifying the noise. This might be useful in some exotic application, but certainly not common.

\$\endgroup\$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.