Hi all,
I'm using R+ and R- combined strain gauge, 3 wires like this :
I connect the common point (RED) to GND and then use TS5A4624 to multiplexe White and Black into a voltage divider and then to an analog to digital conversion block:
It's working quite good but now I try to make it great. Main issue for now is the temperature sensibility.
In my application V+ is 3.0V so the current is about 1.5mA in the multiplexer and my LSB is about 3mohm so about 2nA variation in sensor. So maybe the leakage current variation with temperature is becoming an issue ? Maybe also the discrepancy between R_on on NC versus NO way is getting worse with temperature?
Do you think there is a better component (pin to pin compatible) to keep good matching characteristics between NC and NO ways in temperature (and over time)?
I don't care about variations on both ways as I subtract the results of both measurement to get my useful result. So I just need to avoid mismatch between channels characteristics. Higher R_on ( <50 ohms) are also possible as long as the discrepancy between channel characteristics is better.
Any comments / idea are welcome,
Have a good day,
Thomas