No OSC_IN on STM32H503KB (32-pin QFN)

maxter · ‎2025-06-08

The 32-pin package doesn't seem to have any kind of external clock input at all, and the device does not feature "crystal-less USB". How do we provide a stable clock for USB then?

STTwo-32 · ‎2025-06-09

Hello @maxter and welcome to the ST Community

For the USB, you can use the hsi48_ker_ck according to the table 67 and paragraph 10.4.4 of the RM0492 Rev3. and according to the paragraph 3.10 of the DS14053 Rev4.

Best Regards.

STTwo-32

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STTwo-32 · ‎2025-06-09

Hello @maxter and welcome to the ST Community

For the USB, you can use the hsi48_ker_ck according to the table 67 and paragraph 10.4.4 of the RM0492 Rev3. and according to the paragraph 3.10 of the DS14053 Rev4.

Best Regards.

STTwo-32

To give better visibility on the answered topics, please click on Accept as Solution on the reply which solved your issue or answered your question.