SN65DP149: SN65DP149 Re-Driver/Re-timer closing the eye of the signal

Part Number: SN65DP149

Hi,

We are noticing that the signal coming out of the SN65DP149RSBT is adding significant jitter to the HDMI signal. Below is the input of the IC at pin 6 and 7 ( IN_D0x)

Below is the output of the IC on pin 24 and 25 (OUT_D0)

We have tried settings like slew rate, pre-empasis, de-emphasis and equalization. There is no significant change in signal quality.

Any ideas what is causing it? Any TI folks who comment on this signal issue? We have tried multiple boards with no differences in signal quality.

Thx

over 7 years ago

0 Moises Garcia over 7 years ago

TI__Mastermind 23815 points

Hi KS,

Could you share schematic and layout for review?
Contact your TI FAE to upscale this issue to HelpMe platform, there we can share files securely.

Regards

0 Moises Garcia over 7 years ago in reply to Moises Garcia

TI__Mastermind 23815 points

Hi KS,

Were you able to take eye diagrams from DP149 alone?

Regards

0 Moises Garcia over 7 years ago in reply to Moises Garcia

TI__Mastermind 23815 points

Hi KS,
Do you have any update? I have some other questions

1: eyediagram was took by differential probe or single ended probe?

2: 7.47 inches trace length mismatch is inter-pair or intra-pair?

3: how long of trace length for TX signal?

4: how they terminate output signal?

Regards

Interface

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SN65DP149: SN65DP149 Re-Driver/Re-timer closing the eye of the signal