• State TI Thinks Resolved
  • Locked Locked
  • Replies 4 replies
  • Answers 1 answer
  • Subscribers 33 subscribers
  • Views 763 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.

DP83867IR: pulse-trans is integrated in RJ45

K.Hamamoto
Guru 12155 points
Part Number: DP83867IR

Hi

Our customer is going to use the following RJ45 connector with DP83867.

http://www.taimag.com/PDF/RJ/RJG/RJG-001TC1_A9_20170117.pdf

Is there any concern about using this connector?

We understand that the capacitor will need at center tap of trans. We would like to know other concerns about specification of trans.

Regards,

Koji Hamamoto

  • 0
    TI__Mastermind 19780 points
    Hi Hamamoto-san,

    The RJ45 connector shown does not fit our recommended configuration with the CTs being shorted together.

    Please see the figure 4 in the DP83867 troubleshooting app note to see that the capacitors for the center taps should have separate nets: www.ti.com/.../snla246a.pdf

    The electrical specification of the RJ45 connector is OK.

    Regards,
  • 0 in reply to Rob Rodrigues
    Guru 12155 points
    Hi Rodrigues-san,

    Thank you very much for your prompt reply.

    I am going to recommend to our customer the RJ45 connector that CT's is not sorted together.
    In addition, could you give us any reason or concerns why the center tap should be separated?

    I would like to suggest to our customer with that reason and concerns.

    Regards,
    Koji Hamamoto
  • 0 in reply to K.Hamamoto
    TI__Mastermind 19780 points
    Hamamoto-san,

    When the center taps are joined together in a single net, we have seen cases where the auto-negotiation pulses are reduced in amplitude or cut-off. This could cause unexpected behavior when performing auto-negotiation. This is why we recommend the center taps be separated.

    Regards,
  • 0 in reply to Rob Rodrigues
    Guru 12155 points
    Hi Rodrigues-san,

    Thank you for your prompt reply.

    We have talked with the customer. Then for using that kind of RJ45 connector without individual center-tap they asked us whether it is possible to adding some test as the following.

    cp.literature.agilent.com/.../N5392-97000.pdf

    Is it possible to use the RJ45 connector without center-tap if the above test is passed?

    Because the RJ45 connector with individual center-tap is expensive. So they would like to use the RJ45 connector without individual center-tap.

    Regards,
    Koji Hamamoto