Seeed XIAO BLE nRF52840 Sense

by Seeed Studio

Seeed XIAO BLE nRF52840 Sense is a tiny Bluetooth LE development board designed for IoT and AI applications.

It features an onboard antenna, 6 Dof IMU, microphone, all of which make it an ideal board to run AI using TinyML and TensorFlow Lite.

Features

  • Powerful CPU: Nordic nRF52840, ARM® Cortex™-M4 32-bit processor with FPU operating at 64 MHz
  • Wireless capabilities: Bluetooth 5.0, NFC, and ZigBee module with onboard Bluetooth antenna
  • Ultra-small size: 21 x 17.5mm, Seeed Xiao series classic form-factor for wearable devices
  • Ultra-low sleep power: 5 μA, deep sleep model
  • Battery charging chip: BQ25101 chip supported lithium battery charge management
  • Rich interface: 1x Reset button, Ix UART, 1x IIC, 1x SPI, 1x NFC, 1x SWD, 11x GPIO, 6x ADC, 1x Three-in-one LED,1x User LED
  • Onboard 2 MB flash
  • Onboard microphone
  • Onboard 6-axis IMU
  • Single-sided components, surface mounting design
  • Corresponded to TinyML AI project: Sensing, Processing, Communication 3 in 1 Node

As the advanced version of the board XIAO BLE, Seeed XIAO BLE Sense has equipped a powerful Nordic nRF52840 MCU which is designed in a Bluetooth 5.0 module, built around 32-bit ARM® Cortex™-M4 CPU with Floating-Point Unit(FPU) operating at 64Mhz. With the capabilities of wireless connection, it still remains the Seeed XIAO series classic form-factor of small and exquisite which can be used for wearable devices and Internet of Things projects. Furthermore, it only costs 5 μA in the deep sleep model and it supports battery charge management because of the BQ25101 chip.

In addition, it carries two extra onboard sensors. One of them is a digital microphone created through Pulse Density Modulation(PDM) module on the nRF52840 chip. It can receive audio data in real-time which allows it can be used for audio recognition. The board not only receives audio data but also can speak through the MSM261D3526H1CPM microphone. The other one is 6-axis Inertial Measurement Unit(IMU) which can be applied in TinyML projects like gesture recognition. These onboard sensors provide a great convenience for users and the ultra-small size feature of the board has still remained.

Same as XIAO BLE, Seeed XIAO BLE Sense contains a wealthy interface. The first thing to note is that the Near Field Communication(NFC) is functional on the board. Secondly, there is a tiny and elegant reset button on one side of the Type-C interface. On the other side, it is designed in a three-in-one LED along with a power LED. There are 11 digital i/o that can be used as PWM pins and 6 analog i/o that can be used as ADC pins. It supports UART, IIC, and SPI all three common serial ports. Same as Seeed XIAO RP2040, it has an onboard 2 MB flash which means it can also be programmed by Arduino, MicroPython, CircuitPython, or other program languages.

As XIAO form factor, XIAO BLE Sense supports both Grove Shield for XIAO and XIAO Expansion board. There is a slight difference between the pins and refer to the Pinout it is easy to manage. If you are interested in programming embedded machine learning, Seeed have Codecraft graphic programming that can help you quickly start your own TinyML project. And Seeed have set up a #tinyml channel on their Discord server, please click to join for 24/7 making, sharing, discussing, and helping each other out.

Specification

Processor Nordic nRF52840
ARM® Cortex®-M4 with FPU run up to 64 MHz
Wireless Bluetooth 5.0/NFC/Zigbee
On-chip Memory 1 MB flash and 256 kB RAM
Onboard Memory 2 MB QSPI flash
Interface 1xUART, 1xIIC, 1xSPI, 1xNFC, 1xSWD,
11xGPIO(PWM), 6xADC
Sensors Onboard PDM digital microphone
Onboard 6-axis IMU
Dimensions 21 x 17.5mm
Power Circuit operating voltage: 3.3V@200mA
Charging current: 50mA/100mA
Input voltage (VIN): 5V
Standby power consumption: <5μA

Application

  • Wearable devices
  • Wireless connect
  • Embedded machine learning projects
  • IoT and TinyML AI application
  • Perfect for mini Arduino projects

Attention: All the I/O pins are 3.3V, please do not input more than 3.3V, otherwise, the CPU may be damaged.

Documentation

Learn

  • XIAO BLE - This wiki will help you quickly get started with Seeed XIAO BLE.