Max30102 is an improved design version of better accuracy compared to Max 30100 pulse oximeter . 

The MAX30102 can be used as an oximeter by measuring the oxygen concentration in the blood (SpO2 percentage) and also can be used as heart rate sensor (beats per minute). The device has two LEDs, one emitting red light, another emitting infrared light. For pulse rate, only the infrared light is needed. Both the red light and infrared light is used to measure oxygen levels in the blood. 

How does the max 30102 pulse oximeter work?

When the heart pumps blood, there is an increase in oxygenated blood as a result of having more blood. As the heart relaxes, the volume of oxygenated blood also decreases. By knowing the time between the increase and decrease of oxygenated blood, the pulse rate is determined. 

It turns out, oxygenated blood absorbs more infrared light and passes more red light while deoxygenated blood absorbs red light and passes more infrared light. This is the main function of the MAX30102: it reads the absorption levels for both light sources and store them in a buffer that can be read via I2C.

Features

• Working voltage:  5V
• Integrates both complete pulse oximeter and heart rate sensor .
• Easy-to-use I2C interface.

MAX30102 heart rate and pulse oximeter sensor datasheet