• State TI Thinks Resolved
  • Locked Locked
  • Replies 1 reply
  • Answers 1 answer
  • Subscribers 33 subscribers
  • Views 275 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.

DS25CP102: In Chip pulldown

Fabio Soriano
Expert 4110 points
Part Number: DS25CP102

Hi Team,

I received the following request:

My customer is using 2 ds25cp102  and they want to be able to configure them in all possible ways, even with regards to equalization and pre-emphasis.
To reduce the dimensions of the components they want to use the pull-downs that are in the chip by putting the jumpers on the outside towards VCC

If they configure the pin to '1', but the pulldowns are 20k  they are afraid that 20k ohm are weak if the pin is left open!

Can you comment on it?

Regards,

Fabio

  • 0
    TI__Mastermind 43795 points

    Hi Fabio,

    The internal pulldowns are strong enough the guarantee a valid low state if the pin is left "open" to other voltage or current sources.  The external pullup resistors should be sized appropriately to overcome the 20K pulldown current and result in a VIH level >> 2.0V.  Ideally we recommend using a 1K-2K value for the pullups

    Regards,

    Lee