
100031394 · Seeed Studio

XIAO SAMD21 Plus, powered by the Microchip ATSAMD21G18A ARM Cortex-M0+ processor, brings enhanced flexibility and expandability to the tiny and versatile XIAO SAMD21. While maintaining its low-power performance, Arduino compatibility, and compact footprint, the Plus variant features redesigned castellations and backside pad layout, offering 16 additional GPIOs, integrated Li-ion battery management, dedicated Reset and Boot buttons, and an onboard WS2812 RGB LED. It is ideal for advanced IoT projects, battery-powered wearables, embedded applications, and production-ready SoM designs. (Seeed SKU 100031394)
| Part number | 100031394 |
|---|---|
| Manufacturer | Seeed Studio |
| Category | Development Boards › SAMD / SAM Boards |
| Pins | 14 |
Seeed Studio XIAO SAMD21 Plus pinout
| Pin | Name | Type | Description |
|---|---|---|---|
| 1 | D0/A0 | bidirectional | |
| 2 | D1/A1 | bidirectional | |
| 3 | D2/A2 | bidirectional | |
| 4 | D3/A3 | bidirectional | |
| 5 | D4/SDA | bidirectional | |
| 6 | D5/SCL | bidirectional | |
| 7 | D6/TX | bidirectional | |
| 8 | D7/RX | bidirectional | |
| 9 | D8/SCK | bidirectional | |
| 10 | D9/MISO | bidirectional | |
| 11 | D10/MOSI | bidirectional | |
| 12 | 3V3 | power | |
| 13 | GND | ground | |
| 14 | 5V | power |
Schematic symbol and footprint
Schematic symbol
Footprint: Seeed Studio XIAO (2 x 7, 15.24 mm rows) — to scale, pad 1 in yellow (mm). Check against the datasheet before ordering PCBs.
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