Disclaimer: I’m computer scientist.
I would need some help to get an AD620 amplifier module to work.
Some context is available here in a previous question.
Here is a physical view of the amplifier:
The documentation was unfortunately in Chinese, but I translated it. It is available here.
I managed to amplify the output of my generator (TieDie Handyscope H3-5) and adjust gain, but not with the exact same setup depicted in the image. I needed to connect the ground of the input terminal to the ground of my power source.
I didn’t manage to amplify the signal I need to amplify.
I want to amplify the varying voltage at the terminals of a coil that I didn’t manage to see with my oscilloscope (TieDie Handyscope H3-5). I was expecting that I would see at least the ambient 50Hz noise.
Best Answer
If you are talking about amplifying the coil signal (previous post) then I see where you possible went wrong. I've downloaded the schematic and added what you need to add: -
Basically, as I understand, you connected your coil directly across both inputs. If you do this then you need to add bias resistors from one or both inputs to ground to make the input bias currents (small but still relevant) pass the ground and correctly apply DC levels to your inputs correctly. You might get away with 1 MΩ resistors too but don't go lower than 100 kΩ in case it upsets your experiment.
There was also a small error in the schematic that I fixed although I expect the module you bought to be OK.