Abstract
This study presents a new low power and robust reflectance type optical Photoplethysmography (PPG) acquisition system for the mental distress estimation. The front-end circuit is implemented in the integrated chip with chip area of 1200μm × 1200μm and fabricated via TSMC T18 process. The sensing range of the readout circuit is 20nA to 11μA, and the total power consumption of the readout system is 100μW. The total power consumption of the design chip including the OLED driver power is 1.64mW. The designed acquisition system is applied to the wrist artery of the two healthy patients when they are calculating the pictorial puzzles and when they are in relax state. The statistical deviation of the heart rate (HR) from the average HR is increased when subjects are in the stress. Also, the standard deviation of pulse rate variability (PRV), the dynamic range of pulse repetition time (PRT), and the standard deviation of PRV derivative show the increasing temporal value when subjects are in the stress.