stm32f3 USB D+ pull up resistor

CGaud.1 · ‎2021-05-16

I've designed a board with a stm32F302C8T6 but the MCU dosent show up on windows. I didn't have a pull up resistor on D+. Could it cause that problem or the pull up isint mandaatory?

TDK · ‎2021-05-16

An external pullup is required on the STM32F3 series. It is mandatory per the USB specification. See:

https://www.st.com/resource/en/application_note/dm00296349-usb-hardware-and-pcb-guidelines-using-stm32-mcus-stmicroelectronics.pdf

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View solution in original post

TDK · ‎2021-05-16

An external pullup is required on the STM32F3 series. It is mandatory per the USB specification. See:

https://www.st.com/resource/en/application_note/dm00296349-usb-hardware-and-pcb-guidelines-using-stm32-mcus-stmicroelectronics.pdf

If you feel a post has answered your question, please click "Accept as Solution".