INTRODUCTION
Welcome to the home page of PPG-based Heart-Rate Monitor and Pulse Oximeter Project for ELEN 6350 VLSI DESIGN LABORATORY, Spring 2024 at Columbia University supervised by Professor Peter Kinget. The chip fabrication was generously sponsored by Apple Inc.
Fig 1. Photo of Completed Die
BACKGROUND
Photoplethysmography(PPG) is a non-invasive optical measurement method that is often used for heart rate monitoring purposes. PPG uses a light source and a photodetector at the skin surface to measure volumetric changes in blood circulation. It is useful for monitoring the condition and progression of various cardiovascular-related diseases.
During the Covid-19 epidemic, PPG-based heart rate and oximeter became an increasingly important method for health monitoring as quarantine policies and a shortage of resources made it difficult to visit hospitals and clinics. In respiratory diseases such as Covid-19, PPG is a useful tool to monitor heart rate and blood oxygen saturation, ensuring a timely response to life-threatening conditions such as silent hypoxia caused by Covid.
Figure 2 shows a reflective PPG device measuring the reflection red and IR LED light. In our project, we use a transmitting PPG device where the finger is placed between two LEDs and one photodetector
Fig 2. A reflective-type PPG sensor