XIAO nRF52840 Sense

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

It has an onboard antenna, a 6 Dof IMU and a microphone, making it an ideal board for running AI with TinyML and TensorFlow Lite.

Features

• Powerful CPU: Nordic nRF52840, ARM® Cortex™-M4 32-bit processor with FPU operating at 64 MHz.
• Wireless features: Bluetooth 5.0, NFC and ZigBee module with built-in Bluetooth antenna.
• Ultra-small size: 21 x 17.5 mm, classic Seeed Xiao series form factor for portable devices.
• Ultra-low power consumption in sleep mode: 5 μA, deep sleep model.
• Battery charging chip: BQ25101 chip supports lithium battery charging 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 6-axis IMU
• Integrated PDM microphone
• Single-sided components, surface mount design
• Compliant with TinyML AI project: sensing, processing, communication 3 in 1 node

Scope of delivery

• 1 x XIAO nRF52840 Sense microcontroller
• 2 x 7-pin header for soldering

As an enhanced version of the XIAO BLE board, Seeed XIAO BLE Sense is equipped with a powerful Nordic nRF52840 MCU operating in a Bluetooth 5.0 module with a 32-bit ARM® Cortex™-M4 CPU with 64 MHz floating point unit (FPU). With the capabilities of wireless connectivity, it still remains the Seeed XIAO series classic form factor of small and exquisite that can be used for wearable devices and Internet of Things projects. Moreover, it consumes only 5 μA in deep sleep mode and supports battery charge management thanks to the BQ25101 chip.

It also has two additional onboard sensors. One of them is a digital microphone generated by the Pulse Density Modulation(PDM) module on the nRF52840 chip. It can receive audio data in real time and thus be used for audio recognition. The board not only receives audio data but can also talk through the MSM261D3526H1CPM microphone. The other is a 6-axis Inertial Measurement Unit (IMU) that can be used in TinyML projects such as gesture recognition. These on-board sensors offer great convenience to users, and the ultra-small size of the board has been maintained.

Just like XIAO BLE, Seeed XIAO BLE Sense also has a rich interface. The first thing to note is that Near Field Communication (NFC) is functional on the board. Secondly, there is a small and elegant reset button on one side of the Type-C interface. On the other side is 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 analogue I/O that can be used as ADC pins. It supports UART, IIC and SPI, all three common serial interfaces. Like the Seeed XIAO RP2040, it has a 2 MB flash memory, so it can also be programmed with Arduino, MicroPython, CircuitPython or other programming languages.

As an XIAO form factor, XIAO BLE Sense supports both the Grove Shield for XIAO and the XIAO Expansion Board. There is a small difference between the pins and the pinout is easy to handle. If you are interested in embedded machine learning programming, Seeed offers Codecraft graphical programming to quickly start your own TinyML project. Seeed has also set up a #tinyml channel on their Discord Server.

Technical Data

• Prozessor Nordic nRF52840
• ARM® Cortex®-M4 with FPU (up to 64 MHz)
• Wireless Bluetooth 5.0/NFC/Zigbee
• 1 MB Flash On-Chip-Storage + 256 kB RAM
• 2 MB QSPI-Flash Onboard-Storage
• Interface: 1 x UART, 1 x IIC, 1 x SPI, 1 x NFC, 1 x SWD,11 x GPIO (PWM), 6 x ADC
• Sensors: Embedded digital PDM-microphone and onboard 6-axis-IMU
• Dimensions: 21 x 17.5mm
• Operating circuit voltage : 3.3V@200mA
• Charge current: 50mA/100mA
• Imput voltage (VIN): 5V
• Standby current consumption: <5μA

Application

• Body-worn-devices
• Wireless Connections
• Embedded Machine Learning Projects
• IoT and TinyML AI application
• Perfectly for Mini-Arduino-projects

Attention! All I/O pins are operated with 3.3 V, please do not enter more than 3.3 V, otherwise the CPU may be damaged.

Dokumentation

• BQ25101 datasheet
• ST LSM6DS3TR datasheet
• mic-MSM261D3526H1CPM
• Nano BLE MCU-nRF52840 PS v1.1
• bottom pad positioning
• Seeed XIAO nRF52840 v1.0 SCH
• Flash_P25Q16H-UXH-IR datasheet
• Seeed XIAO BLE nRF52840 BLE-Communication distance test report

Wikipedia

BLE - This wiki helps to begin to work with Seeed XIAO BLE fast.