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Hi team,
One of our customer's issues, I'm forwarding it below, could you please provide some troubleshooting suggestions
We use LMK04821EVM to evalute our application, that need 10MHz clock（Using A Rubidium Oscillator） as input reference clock, not use default 122.88MHz clcok.
When we using default 122.88MHz clcok as input clock to OSCIn, the PLL2 show can locked.
But we try switch to 10MHz clock as input to OSCIN, Single PLL. We cann't config the EVB to locked.
So, is there any suggestion or guidance to our seeing? Thanks a lot~
The attached configure:
Input clock： 10MHz， Output Clock：1000MHz，Using VCO1=3000MHz.
The configure can refer following. Now PLL2 cannot lock, Is there any thing can improve? Thanks a lot
Best Regards,
Amy Luo
Hi Amy,
Most likely issue is that the EVM is onboard XTAL is still connected and thus PLL cannot lock. Board must be reworked in order to use OSCin/* with external reference source.
Refer to device schematic at the end of user guide on how to rework board:
Regards,
Vicente
