A Unified Potentiostat For Electrochemical Glucose Sensors

A unified potentiostat circuit for both O-2- and H2O2-based electrochemical glucose sensors was proposed and its function was verified by circuit simulations and measurement results of a fabricated chip. This circuit consisted of an operational amplifier, a comparator and current mirrors. The proposed circuit was fabricated with a 0.13. thick oxide CMOS process and an active area of 360 mu m x 100 mu m. The measurements revealed an input operation range from 0.5 V to 1.6 V in the H2O2-based bio-sensor and from 1.7 V to 2.6 V in the O-2- based bio-sensor with a supply voltage of 3.3 V. The evaluation results showed that the proposed potentiostat circuit is suitable for measuring the electrochemical cell currents of both O-2- and H2O2-based glucose sensors.