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ADV7611 Failing TMDS Jitter Tolerance Compliance Test

Question asked by yairh on May 27, 2015
Latest reply on May 29, 2015 by yairh

Hi,

 

Using the ADV7611 unfortunately we are failing HDMI TMDS Jitter Tolerance Compliance test (8-7) (D-Jitter and C-Jitter) using  Type 3 cable emulation at 148.5MHz.

Other 27 MHz and 148.5 MHz cable tests pass ok.

All electrical test results are ok as well.

 

There seems to be quite a few discussions dealing with Jitter compliance issues on various devices.

Going through them I understand that the failures are most probably associated with equalizer settings.

 

The updated ADV7611 register settings recommendations (May 2014, Rev 1.5) for the equalizer seem to be the following :

68 8D 04 ;  LFG Port A

68 8E 1E ; HFG Port A

 

These are implemented in our code but with the following inaccuracies:

  • We also set the following:  

68 90 04

68 91 1E

Apparently these found their way from the ADV7612 into our settings as port B equalizer values (but have a different meaning for the ADV7611)

  • We have the Equalizer Dynamic Control = Disabled  (HDMI, 0x96[0]=0).

(It does not appear explicitly in the recommended settings)

 

In addition I should point out that NEW_VS_PARAM  is being disregarded (HDMI, 0x4C[2]=0),

and that our software does not change any of the above settings dynamically.

 

We do not have our own test setup and therefore need to apply whatever solution we come up with directly at the ATC resubmission.

 

Appreciate any help on the above.

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