Latest firmware for the MAXREFDES103# is now available


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The MAXREFDES103# is a wrist-worn wearable form factor that demonstrates the high sensitivity and algorithm processing functions for health-sensing applications. This health sensor band platform includes an enclosure and a biometric sensor hub with an embedded algorithm for heart rate and SpO2 (MAX32664C) which processes PPG signals from the analog-front-end (AFE) sensor (MAX86141). Algorithm output and raw data can be streamed through Bluetooth® to an Android® app or PC GUI for demonstration, evaluation, and customized development.

Design files, firmware, and software can be found on the Design Resources tab. The board is also available for purchase.



  • Photoplethysmography (PPG)
  • Wrist-based embedded heart rate, blood oxygen saturation (SpO2) algorithm
  • Heart rate variability (HRV), respiration rate, sleep quality library algorithm
  • Wearable health band form factor
  • MAX32664 sensor hub
  • MAX86141 PPG analog front-end
  • 3-axis accelerometer
  • Windows® and Android GUIs


Designed, Built, Tested



Board pictured here has been fully assembled and tested.

All Design Files


Hardware File


Each file includes schematic, BOM, PCB layout, fab package, and PCB CAD

Details Section


The MAXREFDES103# contains enables quick evaluation of our hardware and embedded firmware for heart-rate and SpO2 monitoring on a wrist-based platform to significantly shorten development time for custom fitness, health, and clinical applications.

The MAXREFDES103# platform includes the following key components

  • Micro board, which includes the MAX32630 microcontroller, MAX20303 power-management IC (PMIC), dual-mode Bluetooth, and 6-axis accelerometer and gyroscope
  • Sensor board, which includes the MAX86141 AFE, optical heart-rate sensor with one green LED, one red LED, one IR LED, two photodiodes, and MAX32664C biometric sensor hub with an embedded algorithm for heart rate and SpO2 monitoring
  • MAXDAP Pico Adapter board for use during a firmware upgrade for the micro board
  • Health sensor band enclosure and straps
  • Hardware design files, firmware, and software