AD9213 MCS in averaged SYSREF mode

1. How do I verify the MCS in averaged SYSREF mode ?

The data sheet let me check MCS lock by Register 0x151E.Does this mean that the synchronization is successful?


2、How to set the delay between local SYSREF and LMFC ?


I read the same value of Register 0x1519(hold status and set up status) by resetting.but it's not best setup and hold margin, so I want to change the delay.

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    •  Analog Employees 
    on Jun 15, 2021 5:29 PM in reply to Jamey

    Hi Jamey,

    The contents of Register 0x1623 through Register 0x1626 show the time difference between the externally applied SYSREF_x signal and the averaged internal "local" SYSREF. This time difference being < one ADC clock period is additional confirmation of synchronization.

    If you are achieving MCS lock, I believe you do not need to worry about the contents of Register 0x1623 through Register 0x1626. Achieving MCS lock means that the internal "local" SYSREF signal has been properly created. The internal "local" SYSREF will identify which ADC clock edge to use for aligning the LMFC. My understanding is that as long as the time difference from Registers 0x1623 through 0x1626 is less than one ADC clock period, then the same ADC clock edge will be identified. That being the case, larger or small is not relevant.

    You can use Register 0x1623 through Register 0x1626 to monitor drift in "local" SYSREF. If the time difference exceeds one sample clock period, you will no longer have MCS lock. In that case you can go through the MCS Averaged SYSREF procedure again to request MCS lock.

    Thank you.

    Doug