AnsweredAssumed Answered

ADV7341 delay between Cb and Cr

Question asked by Ginux on Mar 4, 2016
Latest reply on Mar 8, 2016 by JeyasudhaMuthuPerumal

Hi, I have a question about the delay I'm facing on my ADV7341 output.

 

I use servals ED/HD format and have the same problem for all.

 

Input: YCbCr 20bits 4:2:2 SDR with the appropriate "output-std" (EAV/SAV sync)

Output: YPbPr

 

I see with the scope that on my "Vertical Color Bar" pattern have a delay problem between Cb and Cr (about 25 ns for 1080i@60Hz /  34ns for 720p30).

 

See attached (720p30):

tek_720p30_zoom_mid_line.png (transition between green and puple)

tek_720p30_zoom_first_transition.png (transition between withe and yellow)

tek_720p30_line.png (full line)

tek_720p30_frame.png  (full frame)

 

 

I tried to swap Pb and Pr (Pb transition occur always before Pr) so it doesn't look like a hardware problem on DAC...

 

Any idea of the source of this problem is welcome.

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