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ADV7180: video quality difference between 8bit and 16bit

Question asked by acid on Mar 17, 2018
Latest reply on Mar 19, 2018 by PoornimaSubramani

As I understand the 64-TQFP version can send data using 16 bits (8 bits for Y and 8 bits for Cr/Cb). Other packages have only 8-bit version (Y/Cr/Y/Cb). Usually when chip outputs data in 8-bit words (or bytes) then the pixel clock is 27MHz and when outputs data in 16-bit words then nominal pixel clock is 13.5MHz. In such scenario amount of data send from ADV7180 is the same, but in PDF there is information that 16-bit words can be send using 27MHz pixel clock (OF_SEL[3:0]=0010 and LLC_PAD_SEL[2:0]=000). In this case there is more data send in the same time.

 

Is this setting correct or does 16-bit mode require setting LLC_PAD_SEL[2:0] to 101 (13.5MHz)?

 

If such setting is correct then at least potentially video resolution in 16bit/27MHz is twice as high as in 8bit/27MHz or 16bit/13.5MHz. Am I right?

 

If yes then it means that at least theoretically video quality of ADV7180 in 64-TQFP package can be higher than ADV7180 in other (8bit only) packages, so is ADV7180/64-TQFP any better than others or just each pixel is sent twice in 16bit/27MHz mode?

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