Introduction
Welcome to the home page of the Pulse Oximeter Based Heart Beats Rate Monitor Project. Please feel free to use the navigation bar above to learn more about the project.
This project was part of the course "VLSI Design Lab (E6350)", taught by Professor Peter Kinget in Spring 2015 at Columbia University. Our project was possible due to the generous contribution of MOSIS under their educational program who offered to fabricate the IC that we designed.
This course primarily focused on exposing students to the entire IC design flow. Under supervision, students were required to do all the steps of the chip development process: defining the application and specifications of the IC, system and transistor level simulations, layout, parasitic extraction and post-layout simulations, tape-out to the foundry, and finally experimental verifications on the fabricated IC.
The pulse oximeter based heart beats rate monitor system is designed to detect the heart rate by simply clip the sensor to one's finger. The chip can monitor the heart rate using Photophlethysmogram (PPG) technique as shown in the figure below, which is a non-invasive method to detect the change in blood volume that is periodic since it is caused by the heartbeat.
Principle of Photophlethysmogram (PPG)
In this project, the chip detects the PPG signal from the fingertip. The signal the heart rate monitor chip is dealing with voltage flutuation at the output of the sensor caused by the change of light absorption through the skin. The DC component of the signal indicates the bulk absorption of the skin tissue, and the AC component indicates the variation in blood volume in the skin caused by the pressure pulse of the cardiac cycle.[1]