I think I already know the answer to this, but it seems that in order to get 48 MHz operation from an external crystal, it is necessary to use a 9.6 MHz crystal, a 19.2 MHz crystal, or an external 48 MHz oscillator, is this correct? It doesn't appear that this is possible using an 8 MHz or 16 MHz crystal, which are readily available.
已解决! 转到解答。
Hello David:
I think you are correct, the FLL reference clock divider and the fixed 1280 multiplication factor will not allow you to use 8 MHz or 16 MHz crystal. An alternative would be to use FEI mode and trimming the internal reference clock to 37500 Hz.
Regards!,
Jorge Gonzalez
-----------------------------------------------------------------------------------------------------------------------
Note: If this post answers your question, please click the Correct Answer button. Thank you!
-----------------------------------------------------------------------------------------------------------------------
Hello David:
I think you are correct, the FLL reference clock divider and the fixed 1280 multiplication factor will not allow you to use 8 MHz or 16 MHz crystal. An alternative would be to use FEI mode and trimming the internal reference clock to 37500 Hz.
Regards!,
Jorge Gonzalez
-----------------------------------------------------------------------------------------------------------------------
Note: If this post answers your question, please click the Correct Answer button. Thank you!
-----------------------------------------------------------------------------------------------------------------------