Seeed XIAO nRF52840 Sense

The Seeed XIAO nRF52840 Sense has equipped a powerful Nordic nRF52840 MCU which is designed in a Bluetooth 5.0 module, built around a 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 the 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 the 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 remained.

The Seeed XIAO nRF52840 Sense contains a wealthy interface. The first thing to note is that 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 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 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 has 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.

We also stock the standard Seeed XIAO nRF52840.

This comes in two options: board + headers and a pre-soldered board option. Please select an option before adding to cart.

Note:

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

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:
  • Board + Loose Headers: Seeed 102010469
  • Pre-soldered Board: Seeed 102010632

Specifications

Processor	Nordic nRF52840
	ARM® Cortex®-M4 with FPU run up to 64 MHz
Wireless	Bluetooth 5.0/NFC
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

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

Package Contents

• 1x Seeed XIAO nRF52840 Sense
  • Either pre-soldered or board + loose headers (select before adding to cart)