High-Sensitivity Photodetection Sensor Front-End, Detecting Organophosphorous Compounds for Food Safety

摘要

A high-sensitivity, high dynamic range photodetection sensor front-end is presented, suitable for low-cost hand-held food safety systems. This sensor front-end for detecting organophosphorus (OP) compounds incorporates an on-chip deep N-well photodetector, pulse width modulation (PWM), and a folded reference. Designed in a 0.18μm process, measurement results show an input optical power dynamic range of 71 dB, a sensitivity of 3.6nW/cm~2 (0.77pA), and a power consumption of 14.5μW. OP compound detection experiments demonstrate a limit of detection (LOD) of 0.16μmol/L, comparable to that of a commercial spectrophotometer.