A Reflectance Pulse Oximeter Design Using the MSP430F149

This paper will design a non-invasive optical pulse oximeter using the MSP430F149 single-chip as system microcontroller. The planned pulse oximeter consists of a sensor and a system microcontroller. The sensor is used for the pulse wave´s detection, and the microcontroller is designed to analyze the pulse wave to calculate the oxygen saturation (SaO₂) and pulse rate. The results are displayed on a LCD glass or transported to PC. This paper designs a reflectance pulse oximeter sensor that includes two light emitting diodes (LEDs), one in the visible red spectrum (660 nm) and the other in the infrared spectrum (890 nm). The oxygen saturation is calculated by the intensity from each frequency of light after it reflects through the body tissue. The pulse oximeter uses the MSP430F149 as microcontroller, which has ultra low power capability, so the system´s power consumption is very low.