TY - JFULL AU - Jung-Chuan Chou and Chang-Chi Lee PY - 2009/6/ TI - Design of Measurement Interface and System for Ion Sensors T2 - International Journal of Electronics and Communication Engineering SP - 1106 EP - 1110 VL - 3 SN - 1307-6892 UR - https://publications.waset.org/pdf/10937 PU - World Academy of Science, Engineering and Technology NX - Open Science Index 29, 2009 N2 - A measurement system was successfully fabricated to detect ion concentrations (hydrogen and chlorine) in this study. PIC18F4520, the microcontroller was used as the control unit in the measurement system. The measurement system was practically used to sense the H+ and Cl- in different examples, and the pH and pCl values were exhibited on real-time LCD display promptly. In the study, the measurement method is used to judge whether the response voltage is stable. The change quantity is smaller than 0.01%, that the present response voltage compares with next response voltage for H+ measurement, and the above condition is established only 6 sec. Besides, the change quantity is smaller than 0.01%, that the present response voltage compares with next response voltage for Clmeasurement, and the above condition is established only 5 sec. Furthermore, the average error quantities would also be considered, and they are 0.05 and 0.07 for measurements of pH and pCl values, respectively. ER -