ADV7513 output amplitude

I have a question about the ADV7513 HDMI differential output amplitude.  Is there a registers/ hidden registers  on the ADV7153 that could control the driver output amplitude of the HDMI channel 0 to 2 and clock driver?  I look through the programming guide document of the ADV7513 and it does not listed a register to control that.  The customer complaints the output amplitude of the HDMI signal and want to tune it down to match with the HDMI port 1 and port2 amplitude that output from Nvidia SOM.     


Looking forward for your reply

  • 0
    •  Analog Employees 
    •  Super User 
    on Nov 12, 2018 4:46 PM

    These registers are not meant to be released since we have not tested the various setting against all corners except for the default values in conjunction with the default R_SET value.  You will have to self certify your design.  We still recommend the register values per the script files

    0xA2[2] => TMDS Data channel level, 0=400mV (default), 1 = 500mV

    0xA2[1:0] => Drive Current, 00 = slow (default), 01 = mid, 10 = high

    Same bits apply to 0xA3 for TMDS clock

    To decease the differential amplitude you might try increasing R_SET value by 50 - 100 Ohms or so.

    Basically you are on your own if you change any of the values.  We just have not done excessive tested outside of the default values.