Design of Body Fluid pH Detection Circuit Based on CMOS-ISFET

Body fluid pH is an important indicator of the health of the human body, and potentiometric sensors can be used to determine the health of people by measuring body fluid pH. However, most of these sensors face the limitations of low sensitivity and high cost. In this paper, we propose three pH sensor schemes based on the CMOS-ISFET process and complete the simulation of these three schemes. They are available in different precision CMOS processes $ 0.5\mu$mCMOS, $ 0.6\mu$mCMOS, and 65nm CMOS, while their sensitivities are 11 mV/pH, 5SmV/pH, and 43 mV/pH respectively. Each of these three schemes has its advantages and disadvantages, giving their respective options in different processes, different scaling relationships, and different precision, providing a diversity of options in future multifunctional chips.