Pulse oximeter sensor MAX30101, optical heart-rate and SpO2 module, supply 3.3–5V DC

MAX30101 is an integrated optical sensor module for measuring heart rate and blood oxygen saturation (SpO2). Designed for operation from 3.3 V to 5 V DC, the module combines red and infrared LEDs, a photodetector and low-noise optics in a compact package suitable for wearable and embedded projects. The sensor implements reflective pulse oximetry and provides a small footprint and simple electrical interface for rapid prototyping and integration into health-tracking devices and measurement systems.

Advantages

The MAX30101 module integrates illumination and detection elements with signal conditioning to deliver reliable photoplethysmographic (PPG) signals while minimizing external components. Its wide supply range (3.3–5 V) allows compatibility with common microcontrollers and development boards. Low-noise optics and on-board LEDs reduce the need for additional analog front-end hardware, making it convenient for compact designs and battery-powered applications. The module’s compact dimensions and standardized pin interface simplify placement in prototypes and wearable enclosures.

Suitable for (tasks / use cases)

• Wearable heart rate monitoring (wristbands, smart patches)
• SpO2 measurement in health-tracking devices
• Prototyping biomedical sensors and embedded systems
• Activity trackers and fitness electronics requiring reflective pulse oximetry
• Educational projects and development-board experiments

Key specifications

• Operating voltage range: 3.3–5 V DC
• Sensing method: reflective pulse oximetry (photoplethysmography)
• Integrated components: red and infrared LEDs, photodetector, low-noise optics
• Output: analog PPG signal suitable for microcontroller ADC or digital front-end processing depending on host implementation
• Form factor: compact module for embedded and wearable placement

How to use

Connect power (3.3–5 V) and ground, and interface the module to your microcontroller or ADC input per the module’s pinout. Place the sensing area in contact with the skin surface where blood perfusion is present (fingertip, wrist, or earlobe) to obtain reflective PPG signals. Adjust sampling rate and LED drive settings in firmware to balance signal quality and power consumption. Use filtering and signal-processing algorithms on the host side to extract heart rate and SpO2 values from the raw photodetector readings.

Usage recommendations

For best results, ensure good skin contact and minimize motion during measurement. Calibrate signal-processing parameters for your intended placement (wrist, fingertip) and test under expected ambient light conditions. When using battery power, consider reducing LED drive intensity and sampling frequency to extend operating time while maintaining acceptable measurement accuracy.