Can I use USB high speed on stm32f746vet6 with internal phy?

[nguen nguyen]

what difference between internal and external phy

[Khouloud GARSI · Accepted solution]

Hi @nguen nguyen​ ,

In the STM32F746 MCUs there is two USB 2.0 device/host/OTG controllers:

• The first is a FS controller with on-chip FS PHY
• The second is FS/HS controller integrating the transceivers for FS operation, and featuring an ULPI for HS operation: an external HS PHY connected to the ULPI is required.

-> If you want to build your own USB HS application, you have to add an external HS PHY: No on-chip HS PHY embedded in the STM32F746 devices.

Just for your information:

1. the STM32F7x3 devices have an embedded on-chip HS PHY.
2. I advise you to refer to application note AN4879 for more details about USB peripherals embedded inside STM32 MCUs and to have an idea about HW guidelines for PCB design required to ensure electrical compliance with USB standards.

Link to the AN:

https://www.st.com/content/ccc/resource/technical/document/application_note/group0/0b/10/63/76/87/7a/47/4b/DM00296349/files/DM00296349.pdf/jcr:content/translations/en.DM00296349.pdf

Khouloud.

[nguen nguyen]

thank so much I think shout use STM32F7x3