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* http://www.radio-electronics.com/info/circuits/opamp_non_inverting/op_amp_non-inverting.php
I do not want to hijack the thread
if the answer is "no", that'll be a different topic one day.
While INA333 will work, I think it's a bit of luxury here.
Hello,I have a handmade dissolved oxygen sensor, as described here https://wiki.metropolia.fi/display/sensor/Dissolved+Oxygen+Sensors#DissolvedOxygenSensors-GalvanicElectrode. After looking at the values it outputs with a DMM at 0% and 100% oxygen saturation, my particular sensor is outputting current in the range of 0 to 25 microamps, and the voltage eventually stabilizes around 500+ mV. I have looked at a couple different ways to measure this small current. Most circuits seem to place importance on interfering as little as possible with the current and voltage, however that isn't a requirement for reading this sensor. I am considering using an INA219 http://www.ti.com/lit/ds/symlink/ina219.pdf with a 100 or 1000 ohm shunt resistor since voltage drop doesn't matter. The INA219 has a built in op amp and high resolution ADC, so this is the simplest way that I have found, but I am here to ask if there are any other approaches to measuring such a small current when interference isn't an issue and also if the high shunt resistor approach is a reasonable solution for what I'm trying to do. Thanks for your help.