Most Cortex-M4 MCUs are described by their flash and clock. The AT32F402 and AT32F405 sub-families are better described by what they connect to: USB at full or high speed, and CAN-FD. That combination is exactly what a lot of modern boards actually need — a fast link to a PC or a display, and a resilient bus to motors, cells or sensors. This guide focuses on these two sub-families and when to reach for them.
1. Why the F402 / F405 matter
A Cortex-M4 with FPU already covers the compute. The differentiator is the I/O mix. The F402/F405 bring:
- USB 2.0 — full-speed on the F402 and high-speed options on the F405, with on-chip PHY to reduce external components.
- CAN-FD — higher payload and data-phase bit rate than classic CAN 2.0B.
- Cortex-M4 with FPU — DSP-style math for control and signal handling.
- Rich timers and ADCs — the same motor and measurement peripherals the wider AT32F4 family is known for.
2. Choosing the right sub-family
| Need | Reach for | Why |
|---|---|---|
| PC config / HID only | AT32F402 (USB FS) | Smaller, cheaper, simpler to certify |
| Bulk data, USB host, streaming | AT32F405 (USB HS) | High-speed throughput with on-chip PHY |
| Vehicle / robot / BMS bus | Either with CAN-FD | Resilient bus with larger frames |
| Mixed control + connectivity | AT32F405 | Best balance of compute and interfaces |
3. Design checks before you commit
- Confirm the USB PHY option (FS vs HS) matches your connector and cert plan.
- Size the CAN-FD bit-rate and transceiver for your cable length and node count.
- Verify the package and pin count against your board; the F4 family spans many footprints.
- Plan the clock tree so USB and CAN timing both meet specification.
For a wider view of the family, start from the AT32 MCU family overview, and for performance positioning see the AT32F4 high-performance selection guide. We carry the AT32F403ACGT7 as a representative high-performance AT32 part; browse the full MCU range.
Frequently asked questions
What makes the AT32F402 / AT32F405 series different from the general AT32F4 family?
The F402 and F405 sub-families emphasize high-speed connectivity. They pair a Cortex-M4 core with USB 2.0 full-speed or high-speed PHY options and CAN-FD, which suits industrial interfaces, medical peripherals and consumer devices that need fast host or device links plus a robust automotive-style bus.
When would I choose USB high-speed over full-speed?
Choose high-speed when you move bulk data: firmware images, logs, audio or video-class streams, or when acting as a USB host with multiple devices. Full-speed is enough for configuration, HID and small control transfers and is simpler to certify.
What is CAN-FD useful for in an MCU design?
CAN-FD keeps the familiar CAN physical layer and arbitration but raises the payload per frame and the bit rate in the data phase. It is used in vehicles, robots, battery systems and factory equipment where more data must move with the same wiring and noise immunity as classic CAN.
Do you stock the AT32F402 / AT32F405 parts?
We carry Artery AT32 devices as an independent distributor. Send us the exact AT32F4 sub-family part, package and quantity and we will confirm availability and date code for a quote.
About us & trademarks: JTDZ Tech (Shenzhen Jingteng Electronics Technology Co., Ltd.) is an independent distributor of electronic components. We are not an authorised distributor or representative of the manufacturers named in this article. Manufacturer and part names are used for indicative purposes only, to help identify the components discussed; all trademarks remain the property of their respective owners. Always verify specifications against the official datasheet before design-in or purchase.
Recommended next steps
If you are sourcing any of the parts mentioned in this guide, we can help you confirm stock, pricing, and lead times quickly.
- Upload your BOM — send your full parts list and receive a consolidated quote within 2 business hours.
- Browse related in-stock lines: Interface Chips / RF Chips.
- Contact our team for hard-to-find or end-of-life components.
