2020-05-09 02:14 AM
Hello
I want to include Crystal Oscillator in my project with STM32F767
According to CubeMX HSE pins are PH0 and PH1.
when it comes to determining values of loading capacitors datasheet suggests that input capacitance must be takes into consideration. However I cannot find anything about that in datasheet.
Could you please give me clues to where to find input capacitance of PH0 and PH1 ?
2020-05-09 03:23 AM
It's not exact, but use the I/O pin capacitance value from I/O static characteristics table, usually 5pF.
JW
2020-05-09 06:47 AM
so 10pf or 15pf should be okay right ?
2020-05-09 12:13 PM
What's wrong with accepting 5pF?
JW
2020-05-09 03:42 PM
manufacturer of the oscillator I use required me that I use double the load capacitance. So since I am accepting your answer and taking copper trace's capacitance into account the most reasonable is 10pf (12 would be better but it is not available at local store)
2020-05-18 07:39 AM
Look to AN2867.
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.