TWR-K60F120 12 MHz Oscillator Needed?

[williamely]

Hi Everyone,

I'm trying to pair down the components on the tower board to just what my product needs for production and after reviewing my code I see that the 12 MHz crystal isn't used by my clock configuration so I want to make sure I'm not missing something before I proceed.

We're using the 50 MHz clock out of our network phy to drive EXTAL and from there the PLL cranks it up to 120 MHz.

Neither the K60N512 or K60D100 boards have it so I thought maybe it was there because the K60F120 is a 120 MHz part (FSL put this on there for a reason, I'm just not sure what the reason is).

As always any help would be greatly appreciated!

[kerryzhou · Accepted solution]

Hi Willian Ely,

      You ask "Neither the K60N512 or K60D100 boards have it so I thought maybe it was there because the K60F120 is a 120 MHz part (FSL put this on there for a reason, I'm just not sure what the reason is)."  This is because the clocking system is not same, the main difference is K60F120 have a system oscillator1, and the K60N512 or K60D100 don't have it , so in  K60N512 or K60D100 board ,there is no 12MHz.

    Now I post the two chip's clocking diagram, it will make you understand more easier!

   K60F120 clocking diagram:

K60D100 clocking diagram:

  Of course you can cut down the 12MHz crystal, but make sure in your configuration don't use the system oscillator1

  I wish it helps you!

Best regards!

Jing