Other Parts Discussed in Thread: OPA4347
I have designed and simulated a low-voltage sensor acquisition and amplifier circuit to amplify low voltage differential input signals to give a DC output voltage.
After the In-Amp I have a Sallen-Key bandpass filter that gives me an output voltage that decreases with input frequency but the simulated results do not do this and are almost linear, the output voltage difference at opposite ends of the bandpass filter are about 30mV which is fine.
The passive High-Pass filter (before the In Amp) was removed from my dev. board as it reduced the input signal by more than 50%.
Is there any logical reason why the actual results differ so much from the simulated results? Could this be a hardware issue?