MAXREFDES104#: Health Sensor Platform 3.0

Wearable and supporting documentation are available under NDA only.

The MAXREFDES104# is a unique evaluation and development platform in a wearable form factor that demonstrates the functions of a wide range of Maxim’s products for health-sensing applications. This third-generation health sensor platform (an advancement of the MAXREFDES101# Health Sensor Platform 2.0) integrates a two-in-one PPG + ECG analog-front-end (AFE) sensor (MAX86176), a human body temperature sensor (MAX30208), a microcontroller (MAX32666), a power-management IC (MAX20360), and a 3-axis accelerometer. The complete platform includes a 3D-printed enclosure and a biometric algorithm hub with an embedded heart-rate, oxygen saturation and ECG algorithms (MAX32670). Algorithm output and raw data can be streamed through Bluetooth to a PC GUI for demonstration, evaluation, and customized development.

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


  • Photoplethysmography (PPG)
  • Biopotential measurement (ECG and EEG)
  • Skin temperature measurement
  • Embedded heart-rate and oxygen saturation algorithms
  • Motion and rotation
  • Wearable form factor

What's in the Box

  • Complete Assembled Wearable
  • BLE USB Dongle (CY5677)
  • USB-A to USB-C cable
  • USB-A to Micro-USB cable
  • Programmer Board (MAXDAP-USB-C)


  • Wrist wearables
  • Chest and abdomen wearables including patches
  • Remote patient monitors
  • Forehead wearables

MAXREFDES104# System Board Enlarge+

System Diagram

MAXREFDES104# Block Diagram

MAXREFDES104# System Board Enlarge+


The MAXREFDES104# is the second generation in our family of health sensor development platforms. Like the previous generation, MAXREFDES101#, the MAXREFDES104# enables quick evaluation of our portfolio of wearable products to significantly shorten the development time for custom fitness, health, and clinical applications.

The MAXREFDES104# platform includes the following key components

  • Micro board: Includes the MAX32666 host microcontroller, MAX32670 algorithm hub, MAX20360 power management IC (PMIC), dual-mode Bluetooth, and flash storage
  • Sensor board: Includes the MAX86176, ECG + PPG AFE, optical heart-rate sensor with three LEDs (Green, Red and IR), and three photodiodes, ECG electrodes, and 3-axis accelerometer
  • Sensor board 2: Includes flex cable with the MAX30208 body temperature sensor
  • 3D-printed enclosure
  • BLE dongle
  • Design files, hardware and software

Quick Start Guide for PC Application

Download the latest MAXREFDES104# PC GUI program located at the MAXREFDES104# web page.

Required equipment:

  • A PC with a spare USB port for configuring and data logging

The MAXREFDES104# board is fully assembled and tested. Use the following steps below to verify proper board operation.

  1. Unzip the PC GUI program to a local folder and run MAXREFDES104GUISetupV033.exe to install the program on the PC.
  2. Connect the BLE USB dongle (included in the kit) to the PC.
  3. Turn on the MAXREFDES104# device.
  4. Run the GUI.
  5. Connect the device to the GUI.
  6. Click on Start for collecting data with default settings.

All Design Files

Download All Design Files

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

Hardware Files:

Software Files


Ultra-Low-Power, Optical PPG and Single-Lead ECG AFE

PPG (MAX86176)

  • Complete Dual-Channel Optical-Data Acquisition System
  • Ultra-Low-Power Operation for Wearable Devices
  • Signal to Noise Ratio (SNR) up to 110dB with Average (Avg) Mode and Off-Chip Filtering

ECG (MAX86176/MAX30005)

  • Clinical-Grade ECG AFE with High-Resolution ADC
  • Very Low Input-Bias Current (-40°C to +85°C)
  • Fully Differential Input Structure with CMRR > 110dB at Power-Line Frequencies


  • Shutdown Current of 0.5μA (typ)
  • 256-Word FIFO for ECG and PPG
  • True Synchronous ECG and PPG Data from Dedicated Signal Paths

PMIC with Ultra-Low IQ Regulators, Charger, Fuel Gauge, and Haptic Driver for Small Li+ System

  • Extend Battery-Use Time Between Battery Charging
  • Easy-to-Implement Li+ Battery Charging
  • Minimize Solution Footprint through High Integration

High Reliability, Ultra-Low Power Microcontroller Powered by Arm Cortex M4 Processor with FPU for Industrial and IoT

  • High-Efficiency Microcontroller for Low Power, High Reliability Devices
  • Flexible Clocking Schemes
  • Power Management Maximizes Uptime for Battery Applications

±0.1°C Accurate, I2C Digital Temperature Sensor

  • High Accuracy and Precision
  • Low Power Consumption
  • Small Size

Low-Power ARM Cortex-M4 with FPU-Based Microcontroller with Bluetooth 5 for Wearables

  • High-Efficiency Microcontroller and Audio DSP for Wearable and Hearable Devices
  • Bluetooth 5 Low Energy Radio
  • Power Management Maximizes Operating Time for Battery Applications

MAXREFDES101#: Health Sensor Platform 2.0