Dear Expert
We are using TI's ADS1292 evaluation board to measure impedance.
Verification block diagram is as follows:
After switching the value of the variable resistance tube, we read the returned voltage value from PC to determine the resistance, and the curve is as follows:.
It can be seen that below 4000Ω, the resistance has a good linearity with the voltage, and the linearity of 5000-9000 is also linear. However, at 4000-5000, the voltage has a significant drop
Repeated for several times, similar results were obtained. The resistance box was tested by external equipment and the resistance value was correct.
I would like to ask if you have encountered such a situation there?What could be causing it?thank you1