i want to compensate offset at the output of amplifier. a arduino board nano board will be connect after amplifier. the max arduino analog input is 5V.
i will connect HMC1001 to AD620, followed by a passive low pass filter followed by another amplification stage.
i would like to amplify from 0.1mV to 1V. but i am not sure about the values of resistor and cap as shown below.
kindly advise.
and i am looking for a arduino shield that comes with breadboard as i need to connect hmc1001, amplifier and RF module to the circuit.
Here is a calculator that will you to do your calculations for the analog portion and hopefully pick parts you have. Not sure you need this but here goes: https://electronicbase.net/low-pass-filter-calculator/. The AD620 requires a - power rail as well as the + rail. There are many switch mode power supplies for just a few dollars that will give you the -5. If you keep R5 at maybe a few KOhm the output swing you probably experience will not hurt the arduino analog input. I am guessing this will be + and - 5 analog supply voltages.
Hi luofan , thanks for the diagram and links. However can you explain what you are trying to are trying to do so we have some context?
I'm puzzled as to why you are using two different IC's.
To adjust the offset you can just add a potential divider across the rails and a high value resistor to the junction of R3 & R4.
As the current demand for a neg rail is very low you could actually use a spare pin on the arduino to generate a square wave that you can feed through a cap and rectify to give a neg voltage.
However this is interesting - so do show us your whole project please?
