TDP158: Using TDP158 in conjunction with PS8339

Roy Hsu

Part Number: TDP158
Other Parts Discussed in Thread: HD3SS215

Hi Team,

Below is an illustration that shows the application of my customer.

They are considering to put a placeholder for TDP158 in case the TMDS perceived at the HDMI connector is too weak.

Since the PS8339 has an internal automatic equalization function, my customer is worried that there might be an issue if our TDP158 is placed too close to the PS8339. (According to my customer, none of Parade's redriver works under this application)

PS8339:

What do you think about this? Could you recommend us a suitable position to place the TDP158?

Or are there any other devices suitable for this application?

Thanks!

Best regards,

Roy Hsu

over 7 years ago

0 Michael.Walker over 7 years ago

TI__Mastermind 19720 points

The main concern that I can see in this design is that the signal will be over equalized. One of the ways to fix this would be to disable pre-emphasis on the PS8339 and use the lowest EQ setting on the TDP158.

Another solution would be to use a passive MUX such as the HD3SS215 with a DP redriver and a HDMI redriver like the TDP158.

0 Roy Hsu over 7 years ago in reply to Michael.Walker

TI__Genius 9360 points

Hi Michael,

Thanks for your feedback!

Other than disabling the pre-emphasis of the PS8339, do you think moving TDP158 closer to the HDMI connector also helps?

If yes, is there a way to determine the distance between the PS8339 and TDP158?

Thanks!

Best regards,
Roy Hsu

0 Michael.Walker over 7 years ago in reply to Roy Hsu

TI__Mastermind 19720 points

Yes, moving the TDP158 closer to the HDMI connector will help with over equalization issues. There is no specific distance, just try to make the TDP158 as close to the connector as possible.

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TDP158: Using TDP158 in conjunction with PS8339