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ADV7181B RGB 4:4:4 640 x 480i configuration

To digitize RGB, 4:4:4, 640 x 480i, square pixel video at a 30Hz frame rate please confirm the following.


·         Need a 28.63636MHz, < 50ppm crystal

·         Table 21 in the user manual shows NTSC square pixel format is supported. Is the square pixel format also supported for RGB?

·         From what I can tell (table 53 in user manual) the only output format for RGB is 12-bit. No way to support 3 x 8?

·         Will LLC = 12.272726MHz or do I have to use a nominal 24.545452MHz oscillator to produce the 12.272726MHz LCC frequency?

·         The download site includes a txt file that shows the settings for various SDP input formats. Do you have something similar for CP and this format in particular?

  • This part has been obsoleted and replace by the ADV7181C.

    Assuming the ADV7181C:

    28.63636MHz 50ppm is the correct crystal

    RGB square pixel: It should however I'll need to check into this deeper.

    DDR mode is the only way to get 24-bit RGB from the part with a 20 bit pixel port. see Table 48.  If you need true 24-bit RGB SDR then you might have to look at the ADV7403.

    This device uses a PPL locked to the 28.63636MHz crystal to generate the correct output pixel rate.  You do not need to another crystal.

    We have scripts for the ADV7181C however I don't see any specific script to do square pixel.  Conversion from a close script should be easy.

  • RGB square pixel mode is not similar to NTSC square pixel mode. RGB will have to go through the CP core, so to support it the part will have to be programmed manually (PLL div ratio, etc...). This is not a standard mode for the ADV7181C, and it has not been tested, so we cannot guarantee that it is going to work.

  • This question has been assumed as answered either offline via email or with a multi-part answer. This question has now been closed out. If you have an inquiry related to this topic please post a new question in the applicable product forum.

    Thank you,
    EZ Admin