LMX2594EVM: Intermittent Locking

Hello Norman, 
I am able to consistently get lock every time with CAL_CLK_DIV set to 'DIV1, Fosc<=200' 
Can you provide more info regarding this? Is this random, predictable? Is this seen on one unit or multiple units? Is there a sequence you follow that guarantees this issue? 

I didn't have a single issue locking using your config. Are you using a Signal generator as your reference? 

Regards, 

Vicente 

It is random on initial register writes after power up and on multiple units.  Once the registers are written after power up even if it comes up unlocked the next write will result in a lock.  I found that if I enable QUICK_RECAL with VCO3 as the start VCO, it always locks first time after power up.  I'm just trying to understand what the QUICK_RECAL is doing and if this is a correct solution?

Hi Norman, 
Can you please provide your initialization sequence step by step please? 
If you load the default mode config, do you manage to achieve lock? 

Regards, 

Vicente 

Yes, it always locks with the default and 100MHz clock input.  If I change the clock input to 160MHz and keep the same output frequency, it works about 50% of the time.

Hi Norman, 
Are you triggering FCAL_EN? I see it's yellowed out: 

Regards, 

Vicente