Hi,
I am trying to amplify a signal that is being produced by a magnet and pickup coil and I eventually want to use this signal to trigger a 555 timer in monostable mode later in the signal chain. I am using this arrangement to sense the movement of a metallic object as shown in the diagram below:.
I am approaching this using an instrumentation amplifier circuit (attached) and am not getting the expected output from the amplifier.
1. Am I applying the amplifier correctly given that my input/source is floating?
2. Is it appropriate to tie the REF pin to ground in this situation?
3. Am I even using the best part for this application?
4. What else am I doing wrong?
A few more details: My input signal frequency range is approx. 1Hz - 500Hz (depending on the speed of the object). I would like to retain the variable gain feature of the instrumentation amplifier so as to adjust the "sensitivity" of detection.
Thanks in advance!