# Seeed Studio XIAO nRF52840 Sense

> Thumb-sized (21×17.8 mm) nRF52840 board (64 MHz Cortex-M4F, 1 MB flash + 2 MB QSPI flash, 256 KB RAM, Bluetooth 5 / NFC) with 6-DoF IMU (LSM6DS3TR-C) and PDM microphone, Li-ion charger (BQ25101), USB-C, RGB LED, 11 GPIO / 6 ADC castellated pads + SWD/NFC/battery back pads; <5 µA standby.

- Manufacturer: Seeed Studio
- Part number: 102010469
- Category: Development boards
- Canonical page: https://www.xirkit.io/products/seeed-studio-xiao-nrf52840-sense-a973
- Pinout: https://www.xirkit.io/products/seeed-studio-xiao-nrf52840-sense-a973/pinout
- Structured JSON: https://www.xirkit.io/products/seeed-studio-xiao-nrf52840-sense-a973/data.json
- Source: Xirkit structured parts catalog — every value traced to a cited document; unknowns are explicit.

## Key specifications

| Property | Value |
| --- | --- |
| Main chip | nRF52840-QIAA |
| Chips on board | nRF52840-QIAA |
| Exposed GPIO | 11 |
| Documented board pins | 22 |
| I/O voltage | 3.3 V |
| Supply voltage | 5–5 V |
| Flash | 1,024 KB |
| SRAM | 256 KB |
| Interfaces | gpio, pwm, adc, pin_select, i2c, uart, spi, nfc, debug, control, usb |
| Frameworks | Arduino, MicroPython, CircuitPython |
| Dimensions | 21 × 17.8 × 1.6 mm |

## Pinout (22 pins, 14 with electrical limits)

| Pin | Position | Kind | Chip pad | Functions | VIH | VIL | VOH | VOL | IOH | IOL | 5 V tolerant |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| D0 | castellated_edge · L1 | gpio | P0.02 | D0, P0.02, PWM, Analog, AIN0, any digital peripheral via PSEL (UART/SPI/TWI/PWM/QDEC/I2S/PDM) | 2.31–3.3 V | 0–0.99 V | 2.9–3.3 V | 0–0.4 V | 1–4 mA | 1–4 mA | no |
| D1 | castellated_edge · L2 | gpio | P0.03 | D1, P0.03, PWM, Analog, AIN1, any digital peripheral via PSEL (UART/SPI/TWI/PWM/QDEC/I2S/PDM) | 2.31–3.3 V | 0–0.99 V | 2.9–3.3 V | 0–0.4 V | 1–4 mA | 1–4 mA | no |
| D2 | castellated_edge · L3 | gpio | P0.28 | D2, P0.28, PWM, Analog, AIN4, any digital peripheral via PSEL (UART/SPI/TWI/PWM/QDEC/I2S/PDM) | 2.31–3.3 V | 0–0.99 V | 2.9–3.3 V | 0–0.4 V | 1–4 mA | 1–4 mA | no |
| D3 | castellated_edge · L4 | gpio | P0.29 | D3, P0.29, PWM, Analog, AIN5, any digital peripheral via PSEL (UART/SPI/TWI/PWM/QDEC/I2S/PDM) | 2.31–3.3 V | 0–0.99 V | 2.9–3.3 V | 0–0.4 V | 1–4 mA | 1–4 mA | no |
| D4 | castellated_edge · L5 | gpio | P0.04 | D4, P0.04, PWM, Analog, SDA, AIN2, any digital peripheral via PSEL (UART/SPI/TWI/PWM/QDEC/I2S/PDM) | 2.31–3.3 V | 0–0.99 V | 2.9–3.3 V | 0–0.4 V | 1–4 mA | 1–4 mA | no |
| D5 | castellated_edge · L6 | gpio | P0.05 | D5, P0.05, PWM, Analog, SCL, AIN3, any digital peripheral via PSEL (UART/SPI/TWI/PWM/QDEC/I2S/PDM) | 2.31–3.3 V | 0–0.99 V | 2.9–3.3 V | 0–0.4 V | 1–4 mA | 1–4 mA | no |
| D6 | castellated_edge · L7 | gpio | P1.11 | D6, P1.11, PWM, TX, any digital peripheral via PSEL (UART/SPI/TWI/PWM/QDEC/I2S/PDM) | 2.31–3.3 V | 0–0.99 V | 2.9–3.3 V | 0–0.4 V | 1–4 mA | 1–4 mA | no |
| 5V | castellated_edge · R1 | power in | — | power_in | — | — | — | — | — | — | — |
| GND | castellated_edge · R2 | ground | — | ground | — | — | — | — | — | — | — |
| 3V3 | castellated_edge · R3 | power out | — | power_out | — | — | — | — | — | — | — |
| D10 | castellated_edge · R4 | gpio | P1.15 | D10, P1.15, PWM, SPI_MOSI, any digital peripheral via PSEL (UART/SPI/TWI/PWM/QDEC/I2S/PDM) | 2.31–3.3 V | 0–0.99 V | 2.9–3.3 V | 0–0.4 V | 1–4 mA | 1–4 mA | no |
| D9 | castellated_edge · R5 | gpio | P1.14 | D9, P1.14, PWM, SPI_MISO, any digital peripheral via PSEL (UART/SPI/TWI/PWM/QDEC/I2S/PDM) | 2.31–3.3 V | 0–0.99 V | 2.9–3.3 V | 0–0.4 V | 1–4 mA | 1–4 mA | no |
| D8 | castellated_edge · R6 | gpio | P1.13 | D8, P1.13, PWM, SPI_SCK, any digital peripheral via PSEL (UART/SPI/TWI/PWM/QDEC/I2S/PDM) | 2.31–3.3 V | 0–0.99 V | 2.9–3.3 V | 0–0.4 V | 1–4 mA | 1–4 mA | no |
| D7 | castellated_edge · R7 | gpio | P1.12 | D7, P1.12, PWM, RX, any digital peripheral via PSEL (UART/SPI/TWI/PWM/QDEC/I2S/PDM) | 2.31–3.3 V | 0–0.99 V | 2.9–3.3 V | 0–0.4 V | 1–4 mA | 1–4 mA | no |
| NFC1 | back_pads · NFC2 | gpio | P0.09 | NFC1, P0.09, any digital peripheral via PSEL (UART/SPI/TWI/PWM/QDEC/I2S/PDM) | 2.31–3.3 V | 0–0.99 V | 2.9–3.3 V | 0–0.4 V | 1–4 mA | 1–4 mA | no |
| NFC2 | back_pads · NFC1 | gpio | P0.10 | NFC2, P0.10, any digital peripheral via PSEL (UART/SPI/TWI/PWM/QDEC/I2S/PDM) | 2.31–3.3 V | 0–0.99 V | 2.9–3.3 V | 0–0.4 V | 1–4 mA | 1–4 mA | no |
| SWDIO | back_pads · TP5 | debug | SWDIO | SWDIO | — | — | — | — | — | — | — |
| SWDCLK | back_pads · TP3 | debug | SWDCLK | SWDCLK | — | — | — | — | — | — | — |
| RESET | back_pads · TP2 | control | P0.18 | RESET, P0.18, nRESET, any digital peripheral via PSEL (UART/SPI/TWI/PWM/QDEC/I2S/PDM) | 2.31–3.3 V | 0–0.99 V | 2.9–3.3 V | 0–0.4 V | 1–4 mA | 1–4 mA | no |
| GND | back_pads · TP1 | ground | — | ground | — | — | — | — | — | — | — |
| BAT+ | back_pads · BAT0 | power in | — | power_in | — | — | — | — | — | — | — |
| BAT- | back_pads · GND0 | ground | — | ground | — | — | — | — | — | — | — |

## Where to buy

| Supplier | Price | Stock | Checked | URL |
| --- | --- | --- | --- | --- |
| Seeed Studio | 15.9 USD | unknown | 2026-09-24 | https://www.seeedstudio.com/Seeed-XIAO-BLE-Sense-nRF52840-p-5253.html |

## FAQ

**What microcontroller does the Seeed Studio XIAO nRF52840 Sense use?**

The Seeed Studio XIAO nRF52840 Sense is built around the nRF52840-QIAA, alongside LSM6DS3TR-C, MSM261D3526H1CPM, BQ25101YFPT, SGM2040-3.3YUDH4G/TR.

**How many GPIO pins does the Seeed Studio XIAO nRF52840 Sense have?**

11 GPIO pins are exposed. Xirkit documents 22 board pins, 14 of them with pin-level electrical limits.

**Are the Seeed Studio XIAO nRF52840 Sense I/O pins 5 V tolerant?**

No. The I/O pins are not 5 V tolerant — they run at 3.3 V logic; use a level shifter for 5 V signals. Input-high threshold: 2.31–3.3 V.

**How much current can a Seeed Studio XIAO nRF52840 Sense GPIO pin source?**

Documented output-high current per pin: 1–4 mA. Values are traced to the chip datasheet; see the pinout table for per-pin limits and conditions.

**What voltage powers the Seeed Studio XIAO nRF52840 Sense?**

Supply range 5–5 V. Power inputs: 5V, BAT+.

**How much does the Seeed Studio XIAO nRF52840 Sense cost?**

From $15.9 at Seeed Studio. Prices are observed unit prices before tax and shipping.

**What are the Seeed Studio XIAO nRF52840 Sense dimensions?**

21 × 17.8 × 1.6 mm. A STEP model is available for enclosure fit checks.

**Which interfaces does the Seeed Studio XIAO nRF52840 Sense support?**

gpio, pwm, adc, pin_select, i2c, uart, spi, nfc, debug, control, usb.

**How do I program the Seeed Studio XIAO nRF52840 Sense?**

Supported frameworks: Arduino, MicroPython, CircuitPython.

**Where does this Seeed Studio XIAO nRF52840 Sense data come from?**

Every value in this record is traced to a source — 2 documents including the board and chip datasheets — with the page and table cited per value. Unknowns are left explicit, never guessed.

## Sources

- [Seeed Studio XIAO nRF52840 Sense datasheet](https://wiki.seeedstudio.com/XIAO_BLE/)
- [Seeed Studio listing](https://www.seeedstudio.com/Seeed-XIAO-BLE-Sense-nRF52840-p-5253.html)

## Part graph

### Built from

- [nRF52840-QIAA](https://www.xirkit.io/products/category/dev-boards/nrf52840-qiaa) — main processor on the Seeed Studio XIAO nRF52840 Sense
- LSM6DS3TR-C — imu on the Seeed Studio XIAO nRF52840 Sense
- MSM261D3526H1CPM — microphone on the Seeed Studio XIAO nRF52840 Sense
- BQ25101YFPT — battery charger on the Seeed Studio XIAO nRF52840 Sense
- SGM2040-3.3YUDH4G/TR — ldo regulator on the Seeed Studio XIAO nRF52840 Sense
- P25Q16H-UXH-IR — flash memory on the Seeed Studio XIAO nRF52840 Sense

### Alternatives (by use case)

- [Teensy 4.0](https://www.xirkit.io/products/pjrc-teensy-4-0-8ee0) — Both serve custom usb devices (hid, midi, serial) — check the trade-offs; $19.95 vs $15.9
- [Teensy 4.1](https://www.xirkit.io/products/pjrc-teensy-4-1-988c) — Both serve custom usb devices (hid, midi, serial) — check the trade-offs; $29.95 vs $15.9
- [Adafruit Feather RP2040](https://www.xirkit.io/products/adafruit-feather-rp2040-802e) — Both serve battery-powered and portable builds — check the trade-offs; $11.95 vs $15.9
- [Adafruit ESP32-S3 Feather (8 MB flash, no PSRAM)](https://www.xirkit.io/products/adafruit-esp32-s3-feather-8-mb-flash-no-psram-a873) — Both serve battery-powered and portable builds — check the trade-offs; $15.9 vs $17.5
- [STM32 Nucleo-64 NUCLEO-F446RE (MB1136)](https://www.xirkit.io/products/stmicroelectronics-stm32-nucleo-64-nucleo-f446re-mb1136-2179) — Both serve custom usb devices (hid, midi, serial) — check the trade-offs; $18.66 vs $15.9
- [Arduino Nano ESP32](https://www.xirkit.io/products/arduino-nano-esp32-d5fc) — Both serve custom usb devices (hid, midi, serial) — check the trade-offs; $19.3 vs $15.9
- [Arduino Nano RP2040 Connect](https://www.xirkit.io/products/arduino-nano-rp2040-connect-e1b2) — Both serve sensor fusion and on-device ml — check the trade-offs; $21.3 vs $15.9
- [Arduino UNO R4 Minima](https://www.xirkit.io/products/arduino-uno-r4-minima-4540) — Both serve custom usb devices (hid, midi, serial) — check the trade-offs; $20 vs $15.9
- [Arduino UNO R4 WiFi](https://www.xirkit.io/products/arduino-uno-r4-wifi-d7ab) — Both serve custom usb devices (hid, midi, serial) — check the trade-offs; $27.5 vs $15.9
- [ESP32-DevKitC V4](https://www.xirkit.io/products/espressif-esp32-devkitc-v4-01c3) — Both serve connected iot and wireless sensor nodes — check the trade-offs; $15 vs $15.9
- [ESP32-S3-DevKitC-1 (N8R8)](https://www.xirkit.io/products/espressif-esp32-s3-devkitc-1-n8r8-e95f) — Both serve custom usb devices (hid, midi, serial) — check the trade-offs; $19.95 vs $15.9

### Pin-compatible

- [Adafruit QT Py RP2040](https://www.xirkit.io/products/adafruit-qt-py-rp2040-bdcf) — Same Seeed XIAO footprint and pad layout (guide p10) — different main chip
- [Seeed Studio XIAO ESP32C3](https://www.xirkit.io/products/seeed-studio-xiao-esp32c3-99be) — Same form factor and header layout as the Seeed Studio XIAO nRF52840 Sense — pin-compatible, different main chip
- [Seeed Studio XIAO ESP32-S3](https://www.xirkit.io/products/seeed-studio-xiao-esp32-s3-f8f5) — Same form factor and header layout as the Seeed Studio XIAO nRF52840 Sense — pin-compatible, different main chip
- [Seeed Studio XIAO RP2040](https://www.xirkit.io/products/seeed-studio-xiao-rp2040-53de) — Same form factor and header layout as the Seeed Studio XIAO RP2040 — pin-compatible, different main chip