• State TI Thinks Resolved
  • Locked Locked
  • Replies 3 replies
  • Answers 2 answers
  • Subscribers 33 subscribers
  • Views 484 views
  • Users 0 members are here
Support feedback
Options
Options
Related

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

DS125DF410: PPM counter

Lidong Yu
Intellectual 1756 points
Part Number: DS125DF410


What is the PPM Count ? What happens if I don't set the ppm count register?

  • 0
    TI__Expert 8605 points

    Hello,

    The PPM count is the amount of variation allowed from target VCO frequency. It is necessary to set the expected PPM count and the PPM count tolerance as these are the values the retimer uses to detect a valid frequency lock.

    Regards,

    Kia Rahbar

  • 0 in reply to Kia Rahbar
    TI__Intellectual 1756 points

    What if I don't set the PPM count value? I'm using the retimer for only Ethernet mode(1G/10G). Could there be any anticipated problems?

  • 0 in reply to Lidong Yu
    TI__Expert 8605 points

    Hello Lidong,

    If the PPM count is not set, the retimer will not be able to lock to the target VCO frequency and your device will output a data rate that you do not want.

    For more information on how to set the PPM count for Ethernet mode, please reference section 7.4.4 Standards-Based Modes in the DS125DF410 datasheet (section also shown below).

    Regards,

    Kia Rahbar