Several researches are carried out on the readout circuit of the pH-ISFET, we will present in this article a model of readout circuit composed of a caprio’s quad fed by a current source, in addition to two attenuators and a differential amplifier. A HSpice description as well as Veriloge-a were used to simulate the circuit with HSpice. The simulation was done in the temperature range of 20 to 80°C, in the pH measuring range from 1 to 12 and with a supply voltage of 3V. The proposed readout circuit has been simulated in 0.6μm CMOS process. The circuit shows very good performance in term of temperature sensitivity and output linearity. Considering temperature change from 20°C to 80°C, the maximum temperature coefficient is 83.97ppm/°C. Overall, this work provides a framework for designing robust and ISFET-based pH sensors by modeling the drift characteristics and compensating it using particle swarm optimization.
Volume 12 | 04-Special Issue
Pages: 1189-1197
DOI: 10.5373/JARDCS/V12SP4/20201593