• State TI Thinks Resolved
  • Locked Locked
  • Replies 1 reply
  • Answers 1 answer
  • Subscribers 33 subscribers
  • Views 333 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.

DS90UB949-Q1: questions about VTERM pin of DS90UB949-Q1

Betty Guo
Expert 7300 points
Part Number: DS90UB949-Q1

Hi team,

customer use DS90UB949 and builed 40 pcs board, find have two boards can't display normaly. The Deser is 948.

Then, they only change the VTERM pin voltage from 1.8V to 3.3V and keep others circuit constant, the dispaly is normal.So, we have question about VTERM voltage.

the datasheet show the 3.3V is for DC coupled and 1.8V for AC, why some board can work in 1.8V and some can not?

I attached customer scehmatic, please help check and give suggestions. thanks in advance,

DS90UB949t图纸.pdf

  • 0
    TI__Genius 12866 points

    Hi Betty,

    If the customer want to use AC couple termination, they should place AC coupling caps on the HDMI signals.

    Looking at the schematic, currently there's only 0ohm resistors bridging the HDMI signal. In this case, they should use DC coupling which means set VTERM to 3.3V

    Best Regards,

    Charley Cai