External clock signal on FRDM-K66F

[dorustefan_irim]

Hello,

I would need to provide an external clock to replace the 12MHz crystal oscillator with a 10MHz external signal. I have seen so far that the pins for the external clock input are PTA18 and PTA19, but those don't seem to have any connection to the board headers.

Is there any way I could bypass the board crystal oscillator and supply an external clock input to this board using the provided headers ?

[kerryzhou]

Hi Doru,

     If you don't want to use the crystal, just use the 10MHz external signal, you can remove the external crystal and it's circuit, then input the 10Mhz external signal to EXTAL0 pin, it is PTA18.

Wish it helps you!

If you still have question about it, please kindly let me know!

Have a great day,
Kerry

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[dorustefan_irim]

Thanks for the reply! I know that I can remove the oscillator and supply the signal to the EXTAL0 pin, but I need to build a robust prototype and I cannot afford to solder the 10MHz clock signal to the oscillator smd pad. I would prefer to use a connector which is already on the board. Is there any way to reroute the signal to one of the available headers ?

[kerryzhou]

Hi Dorustefan,

  If you use the FRDM-K66F board, it doesn't have the connector to connect the external 10Mhz clock signal to EXTAL0 pin. So, maybe you need to design your own board if you don't want to solder it.

Wish it helps you!

Have a great day,
Kerry

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Note: If this post answers your question, please click the Correct Answer button. Thank you!
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