Introducing a Proposal for the XIAO CAN-FD Expansion Board
Bringing Robotic & Automotive-Grade CAN FD to the XIAO Ecosystem
The XIAO line is beloved for its tiny size and outsized capability—but until now, there has been no way to use true CAN FD with any XIAO board.
Today I’m proposing a fully modern, industrial-strength solution:
XIAO CAN-FD Expansion Board (TCAN4550-Q1 Edition)
Built around Texas Instruments’ TCAN4550-Q1, this board delivers:
- Up to 8 Mbps data-phase
- Supports 64-byte CAN FD frames
- Automotive-grade robustness (AEC-Q100)
- TVS protection, reverse polarity defense
- Selectable 120 Ω termination
- Screw terminal + JST-GH CAN ports
- Compatible with every XIAO MCU via SPI
This opens the door to advanced robotics, AGVs/AMRs, servo networks, industrial automation, and automotive prototyping using XIAO hardware.
If Seeed releases this, the XIAO line becomes one of the smallest, most capable CAN-FD platforms available today.
I believe this board fills a real gap in the ecosystem.
Software Support
- Arduino Library (Send/Receive CAN FD frames)
- Zephyr RTOS Driver (SPI + GPIO IRQ)
- Example applications:
- Motor control + telemetry
- Multi-node robotics bus
- CANopen-FD building blocks
- Sensor aggregation / gateway node
- USB-to-CAN-FD tools using XIAO + this board
Applications
- Collaborative robots (cobots)
- Servo drive networks
- Industrial stepper motor testing (PJ’s application)
- AGVs / warehouse robots
- Automotive ECU prototyping
- CAN-FD dataloggers
- UAV/UGV systems
- Smart factories, Industry 4.0
Mechanical
- Same PCB footprint as the XIAO CAN Bus 2.0 board
- Stackable design
- Mounting holes for industrial panels or robot frames
- 3D printable case available
+------------------------------------------------------+
| XIAO CAN-FD EXPANSION BOARD |
| (TCAN4550-Q1 Inside) |
+------------------------------------------------------+
| XIAO Header Pins |
| [D0] INT <---------------------- TCAN4550 IRQ |
| [D1] CS <---------------------- Chip Select |
| [D2] RST <---------------------- Optional Reset |
| [D8] SCK ----------------------> SPI Clock |
| [D9] MISO <---------------------- SPI Data Out |
| [D10] MOSI ----------------------> SPI Data In |
| |
| TCAN4550-Q1 CAN FD Controller + Transceiver |
| | | |
| +-----+-----+ +-----+-----+ |
| | TX/RX FD | | Protections |
| +-----------+ | (TVS, Reverse) |
| | +-----+-----------+
| CANH | CANL |
| +---------------------------+ |
| | Screw Terminal Block |<---+
| +---------------------------+
| | JST-GH CAN Connector |
| +---------------------------+
|
| [Termination Switch] 120Ω ON / OFF
|
+------------------------------------------------------+
| External Power (5–24 V) (Optional) |
| Onboard Buck → 3.3 V to TCAN4550 |
+------------------------------------------------------+
Proposal Submitted — ready for Seeed Studio review.
Goal: Release as official Seeed XIAO CAN-FD Expansion Board.
Season’s Greetings 
GL 
PJ 
I have an engineering roadmap… also 
Helpful Video
says they are working on Something Game changing for 2026,
XIAO 2.0 — The Compute Module Series
PJ