LMK04821: Output problem

Vayne Li

Expert 1960 points

Part Number: LMK04821

Tool/software:

Hi Teams,

The input of clk0 is 15.36MHz, OSCIN is 122.88MHz, and the output clock of LVDS for all channels is 122.88m and 0.96m. However, currently only 122.88m can be measured, and 0.96m cannot be measured. Changing to other frequency points also cannot be measured. What may be the cause of the problem

9 months ago

0 Michael Srinivasan 9 months ago

TI__Genius 16371 points

Hi Vayne,

I am assuming your 0.96MHz signal is your SYSREF frequency? Have you enabled your SYSREF to be in continuous mode?

Thanks,

Michael

0 Vayne Li 9 months ago in reply to Michael Srinivasan

Expert 1960 points

Hi Michael,

Yes,the customer has already set this mode.I will send you a copy of their configuration.Please help me check where the problem is.

04828_cfg.rar Thank you

0 Michael Srinivasan 9 months ago in reply to Vayne Li

TI__Genius 16371 points

Hi Vayne,

I used the configuration you sent me, changing hardly anything except for the clock input (I changed to CLKin1, had 15.36MHz coming in through that port), and I was able to see all of your outputs, including the 0.96MHz.

Are you triggering a SYNC event? This is necessary to generate SYSREF outputs.

Thanks,

Michael

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LMK04821: Output problem