Dynamic element matching in direct sensor — Microcontroller interface

The resistive and capacitive modulating sensors can be directly measured with microcontroller by measuring the charging or discharging time of RC circuit. One of the uncertainty sources when using one point calibration is the uncertainty of the calibration resistor. This uncertainty can be reduced by using the dynamic element matching technique. In this paper, implementation of this technique by using PIC16F877 microcontroller is presented. The results will be compared with other averaging techniques.