We detect you are using an unsupported browser. For the best experience, please visit the site using Chrome, Firefox, Safari, or Edge. X

High-end wearable activity trackers can take step count, temperature, light and other movement and environment measurements. They are not only being used for fitness applications, but are becoming an essential part of medical device design. Our Ultra-Low-Power (ULP) Connected Wearable Activity Monitor Demonstration Board can be used as the starting point for the design of medical home monitoring, patient tracking and drug delivery compliance devices.

This board is a high-end activity tracker demonstration and development board that not only measures a user’s motion and environment, but it can also be used as a starting point for the design of more advanced activity and biometric measurement devices These types of devices measure and analyze sleep quality, heart rate, body temperature and blood oxygen levels. Bluetooth® connectivity allows the demo to communicate with tablets, smartphones or PCs for IoT capability.

Our ULP Connected Wearable Activity Monitor Demonstration board features the SAM L21high-performance, 32-bit Arm® Cortex®-M0+ based microcontroller (MCU) with Ultra Low-Power technology, the BTLC1000 4.1 Bluetooth Low Energy Module, the ATECC508A CryptoAuthentication™ IC as well as movement and environmental sensor chips.

Download Design Files


Start with the free download of the user guide, schematics and 'C' source code that can easily be modified to your specific application needs. 

This reference demo helps you develop a low-power, connected activity monitoring board with Bluetooth Low Energy capability for medical and fitness IoT applications.*

*Microchip medical reference designs and demos are intended for evaluation and development purposes only. Use of Microchip devices in life support and/or safety applications is entirely at the buyer's risk, and the buyer agrees to defend, indemnify and hold harmless Microchip from any and all damages, claims, suits, or expenses resulting from such use.

System Diagram


Demonstration Highlights


  • Ideal for designs that need medical patient tracking, patient compliance, patient biometric diagnostics, fitness activity tracking, etc.
  • Measures proximity, step count, free fall (detection), gyroscopic motion, ambient temperature, pressure (altitude), humidity and light
  • Allows for easy development of more advanced activity tracker functions (e.g. distance traveled, calories burned, sleep analysis, etc.)
  • Additional biometric measurement capability, such as heart rate, blood oxygen and body temperature can be added to this design using our other reference designs
  • Bluetooth Low Energy module is used to demonstrate smartphone/tablet IoT capability
  • Low overall BOM cost due to high level of integration
  • Powered from a single 3V lithium coin-cell battery

Product Features


SAML21 MCU

  • Ultra low-power, high-performance 32-bit Arm Cortex-M0+ based MCU
  • Up to 256 KB of Flash and 40 KB of SRAM
  • Up to 48 MHz operating frequency
  • Up to 14-channels, 1 Msps 12-bit Analog-to-Digital Converter (ADC)
  • Two 1 Msps 12-bit Digital-to-Analog Converters (DACs)
  • Three op amps
  • Full-Speed USB device and embedded host
  • 16-channel Direct Memory Access (DMA) and 12-channel Event system
  • AES and true Random Number Generator (RNG)
  • 32-bit Real-Time Clock (RTC)
  • Support for up to 81 touch channels (mutual capacitance)
  • 1.62 to 3.63V power supply

RN4871 Bluetooth Low Energy Module

  • Bluetooth 5 certified
  • Easy-to-use ASCII command interface for communication with the host microcontroller
  • Module certified for use in USA, Canada, Brazil, Europe, Japan, Korea, Taiwan and China
  • Mobile application supported in our Bluetooth Data (MBD)
  • Remote configuration capability
  • Ceramic chip antenna or external antenna connection

ATECC608A CryptoAuthentication IC

  • Cryptographic co-processor with secure hardware-based key storage
  • Protected storage for up to 16 keys, certificates or data
  • FIPS SP800-56A Elliptic Curve Diffie-Hellman (ECDH)
  • NIST standard P256 elliptic curve support
  • SHA-256 and HMAC hash including off-chip context save/restore
  • AES-128 encryption/decryption, Galois Field Multiply for GCM

Additional Resources


  • SAM L21 32-bit Arm Cortex-M0+ based MCU
  • BTLC1000 ultra-low power Bluetooth Low Energy module (not recommended for new designs); RN4871 or RN4870 Bluetooth Low Energy modules are recommended for new designs
  • ATECC508A CryptoAuthentication™ IC (not recommended for new designs); ATECC608B CryptoAuthentication IC is recommended for new designs
  • Contact your local sales representative to see a working demonstration of our ULP Connected Wearable Activity Monitor Demonstration Board

Medical Video Channel


Ultra-Low-Power Connected Wearable Activity Monitor