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DS90UH925AQ-Q1: DS90UH925AQ-Q1 & HDCP: Must graphics source / host processor be HDCP enabled to use this SERDES chipset?

Part Number: DS90UH925AQ-Q1

I've an application where I need to send either  RGB 8:8:8     or   YCbCr 4:2:2  formatted data through a serial link. 

I chose DS90UH925AQ because it supports enough input lanes for both types of data + HS, VS, DE, and PCLK   

Our video source is NOT an HDCP compliant source ... in fact, it is just a CMOS camera that outputs parallel LVCMOS data in either RGB 8:8:8 or YCbCr 4:2:2  @ 27MHz pixel clock 

As I understand it from the datasheet, the HDCP cipher functionality of the DS90UH925AQ serializer and DS90UH926Q deserializer occurs only between this chipset ... not the external world.  The HDCP cipher action is transparent to the application.     So my conclusion is that  serializing & deserializing using a video source that does not know or care about HDCP should still function correctly using this chipset.   Is my conclusion here accurate & correct?

Also:   YCbCr 4:2:2 requires 16-bit packets for each clock, leaving 8 bits unconnected to the serializer input.   If I connect all G[7:0] inputs to ground, will the SER/DES functionality be maintained in this transmission mode?

  • Hi Adam,

    Yes, your conclusion is accurate. You can stream the outputs from non-HDCP compliant sources.

    G[7:0] already have internal pull-downs, but if you want to guarantee that they don't toggle, you can connect them to ground. The SerDes functionality should not be affected either way.

    Best,
    Jiashow