Seeed XIAO BLE nRF52840 Sense

As the advanced version of the board XIAO BLE, the 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 in the Seeed XIAO series classic form-factor which can be used for wearable devices and Internet of Things projects. Furthermore, it only costs 5μA in deep sleep and supports battery charge management thanks to 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 the XIAO BLE, the Seeed XIAO BLE Sense contains a wealthy interface. The first thing to note is the Near Field Communication (NFC) is functional on the board. Secondly, there is a tiny reset button on one side of the Type-C interface. On the other side is a three-in-one LED along with 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. It has an onboard 2 MB flash which means it can also be programmed by Arduino, MicroPython, CircuitPython or other program languages.

If you are interested in programming embedded machine learning, Seeed have Codecraft graphic programming that can help you quickly start your own TinyML project. Seeed has also set up a #tinyml channel on their Discord server.

Note:

• Header pins are no longer included with this board
• All the I/O pins are 3.3V, please do not input more than 3.3V or the CPU may be damaged. We also stock the Seeed XIAO BLE nRF52840.

Features

• Powerful CPU: Nordic nRF52840, ARM® Cortex™-M4 32-bit processor with FPU operating at 64 MHz
• Wireless capabilities: Bluetooth 5.0 and NFC, 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
• Product number: Seeed 102010469

Specifications

Package Contents

• 1x Seeed XIAO BLE Sense - nRF52840
  

Header pins are no longer included with this board

Resources

• Product Wiki

Documentation

• 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

Pinout