I am currently designing a 4-20mA current loop with external sensors which work at 12V DC. I saw a differential application on the datasheet of the ADS1115 ADC, but the simple shunt resistor I believe would be OK in my situation. I would like your opinion on the GND side of the shunt resistors, is a 100 ohm (R25) resistor enough?
On a MAX31865ATP there is an analog ground for the analog part of the schematic.
Should I also isolate my 4-20mA or doesn't it matter, because I only need to measure the current passing through the known shunt resistors?
**keep in mind that (R21 to R24) are the same part
Also, is my assumption of the 10 ohm shunt good, providing that the ADC reads from -0.3V to 0.3V? Or should I put a bigger resistor and extend to the input limits of my ADC?