• State TI Thinks Resolved
  • Locked Locked
  • Replies 1 reply
  • Answers 1 answer
  • Subscribers 35 subscribers
  • Views 575 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.

Original question:

TPD2S300: CC Line Capacitor selection

TPD2S300: CC Line Capacitor selection

Shmuel Davis
Expert 2930 points
Part Number: TPD2S300


Dear Aramis P. Alvarez,

In the following thread :-

http://e2e.ti.com/support/interface/circuit-protection/f/389/p/653781/2401161#pi320098=1

In the response : Jan 10, 2018 4:33 PM

You stated :-

"If the total capacitance on the CC channels is outside the range of 200pF -600pF, then the PD communication between both PD controllers might not occur (too much cap might cause too long of a delay)."

What might be the effect if the total capacitance is too low (which from the articles that you sent me it appears the drop in capacitance is much more likely change than the rise - please see my response : Jan 22, 2018 1:12 PM )

Thanks

Shmuel 

  • 0
    TI__Mastermind 33201 points
    Shmuel,

    The most likely issue with too low of a capacitance is that the rise/fall transitions of the PD controllers will get too fast and are likely to "ring" and potentially cause the communication channel to malfunction. It is difficult to predict this behavior completely because of cable, protection, and pd controller variations.

    I have seen it to be a typical practice for every design to have about 220pF capacitors on the CC lines to meet system requirements.

    Regards,
    Chuck