Analog and intelligent calibration system to reduce undesired variables in sodium measurement

This paper highlights some aspects of the calibration design that could aid in the optimization of measurement with ion sensing devices in the presence of undesired variables such as temperature and foreign ions. For this purpose a conditioning circuit has been realized to drive two ion sensors and a temperature one (thermistor). The considered ion sensor is compensated with the signal from the thermistor via a nonlinear analog circuit (divider). The signal issued from the undesired ion sensing is used after digitizing with a 2D feed-forward network to compensate the considered ion sensor against the interfering ion, which is in this study potassium ion. Experimental curves have been reported to show the possibility of designing embedded circuit to enhance measurement accuracy in chemical analysis.