STM32N657X0 with self powered USB-C port

[Niveditha_P]

I am designing an STM32N657X0 based custom PCB which has a USB Type C port. The USB device would be self- powered, i.e, it will not be powered from VBUS. The intended use of this port is to plug the PCB to a host PC, similar to USB flash drive for data transfer. How should the VBUS be managed on the circuit? Should it be monitored by the MCU to sense VBUS? Please share any reference designs if available for self-powered USB C sink devices implemented with STM32.

[RomainR.]

Hello @Niveditha_P 

As there is no VBUS pin on the STM32N6 side, you can refer to RM0486 72.4.2 USB Type-C and power delivery interface implementation.

Figure 976, explains how to use the ADC of the N6 with an external channel for VBUS detection.

Please note that the ADC operates at 1.8V Full Scale, so you will need to use an appropriate voltage divider when using 5V voltage input.

Best regards,

Romain,