interfacing external oscillator to STM32F407igt6

[manjunath]

Hi all,
        I have to interface external oscillator to stm32f407igt6 which is having 16Mhz internal frequency and i need to boost it to 168Mhz frequency by connecting a 25Mhz external  oscillator so can anyone give capacitor and resistor values that i need to interface external oscillator to my STM32F407igt6.


Thank you,

[Dago]

Hi all,
        I have to interface external oscillator to stm32f407igt6 which is having 16Mhz internal frequency and i need to boost it to 168Mhz frequency by connecting a 25Mhz external  oscillator so can anyone give capacitor and resistor values that i need to interface external oscillator to my STM32F407igt6.


Thank you,

Why don't you just use the internal oscillator to clock the internal PLL and use that to multiply the core clock to 168 MHz? Or do you need better frequency stability?

Reference manual page 153: http://www.st.com/st-web-ui/static/active/en/resource/technical/document/reference_manual/DM00031020.pdf

[manjunath]

ya i need good frequency stability , can u please tell me how can i interface 25Mhz to my stm32f407igt6.



Thank you,

[andyturk]

http://www.st.com/st-web-ui/static/active/en/resource/technical/document/application_note/CD00221665.pdf