Study on the Characteristics of the Measurement System for pH Array Sensors

A measurement system for pH array sensors is introduced to increase accuracy, and decrease non-ideal effects successfully. An array readout circuit reads eight potentiometric signals at the same time, and obtains an average value. The deviation value or the extreme value is counteracted and the output voltage is a relatively stable value. The errors of measuring pH buffer solutions are decreased obviously with this measurement system, and the non-ideal effects, drift and hysteresis, are lowered to 1.638mV/hr and 1.118mV, respectively. The efficiency and stability are better than single sensor. The whole sensing characteristics are improved.

Authors:

• Jung-Chuan Chou
• Wei-Lun Hsia

Keywords:

• Array sensors
• measurement system
• non-ideal effects
• pH sensor
• readout circuit.

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