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JDoum.1
JDoum.1
Associate
June 28, 2021
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Hello, I'm wondering how to determine the C4 and C5 values ​​for the 32MHz osscilator of the STM32WB. Do I need to physically place those capacitors, or are they programmable from the HSE configuration parameters? Thank you, Jorg

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    TDK
    TDKBest answer
    June 28, 2021

    They are configurable between 12-16pF. You'll need to choose a crystal that is compatible with that.

    https://www.st.com/resource/en/application_note/dm00403796-precise-hse-frequency-and-startup-time-tuning-for-stm32-wireless-mcus-stmicroelectronics.pdf

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    TDK
    TDKBest answer
    June 28, 2021

    They are configurable between 12-16pF. You'll need to choose a crystal that is compatible with that.

    https://www.st.com/resource/en/application_note/dm00403796-precise-hse-frequency-and-startup-time-tuning-for-stm32-wireless-mcus-stmicroelectronics.pdf

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