• State
  • Locked Locked
  • Replies 3 replies
  • Subscribers 34 subscribers
  • Views 188 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.

TMDS1204: Regarding In clock frequency

prema R
Intellectual 730 points
Part Number: TMDS1204
Other Parts Discussed in Thread: SN65DP159,

Tool/software:

Hi

We are planning to use TMDS1204RNQR with Versal FPGA for HDMI TX and RX. We have only 3 channels each of GTY transceivers for TX and RX.

Regarding TX: Data pairs we can map to 3 GTY TX channels, however for clock we need to see how to source this. Please let us know the IN_CLKN clock frequency.

Regarding RX: we want to know if retimer is required for RX. If used for RX is RCLKOUTN is mandatory to be used or OUT_CLK can be used as input to GTY Ref clock? Can RCLKOUTN/P  be left NC when the retimer is used as sink? please let us know.

  • 0
    TI__Genius 15496 points

    Hi, 

    prema R said:
    Please let us know the IN_CLKN clock frequency.

    This is supplied by the source. If the source uses TMDS HDMI signal, this is 150MHz according to the HDMI 2.0 specification. If you are using FRL HDMI, this lane will act as data lane 3 and therefore needed. 


    prema R said:
    Regarding RX: we want to know if retimer is required for RX. If used for RX is RCLKOUTN is mandatory to be used or OUT_CLK can be used as input to GTY Ref clock? Can RCLKOUTN/P  be left NC when the retimer is used as sink? please let us know.

    Whether retimer is needed will depend on the trace length between the source and the sink. RCLKOUT is not mandatory but is needed when the application requires separate paths for HDMI clock and the data lines. If there is no requirement on the source/sink, OUT_CLK can be used as a input to the ref clock.
    RCLKOUT can be left NC if not used. 

    Please let me know if you have any other questions. 

    Best,
    J

  • 0 in reply to J
    Intellectual 730 points

    please let us know if this IC is equivalent to SN65DP159RGZR, if we are using the retimer only for transmit and in hdmi 2.0.

  • 0 in reply to prema R
    TI__Genius 15496 points

    Hi, 

    TMDS1204 does not signal condition in the same way that SN65DP159 does. 
    SN65DP159 uses the embedded clock data recovery to clean up the high frequency and random jitter from the source if it works in retimer mode while supporting both adaptive and fixed equalization to clean up ISI jitter. TMDS1204 only supports fixed equalization to clean up ISI jitter and does not have the clock data recovery feature. 

    All in all, function wise, SN65DP159 can do the same thing as TMDS1204, but SN65DP159 can do more than what TMDS1204 does in hdmi 2.0. 

    Please let me know if you have any other questions. 

    Best,
    J