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The clock output of port out7 is abnormal, and the other ports have not been tested.

Category: Hardware
Product Number: AD9517-4

The output signal of Test Port 7 is abnormal. The frequency and waveform do not meet the expectations. Assistance in analysis is required. The AD9517 is used as a multi - channel clock for clocks.sch

"AD9517 Setup File"
"Rev.","1.1.0"
""
"Addr(Hex)","Value(Bin)","Value(Hex)"
"0000","00011000","18"
"0001","00000000","00"
"0002","00010000","10"
"0003","11010011","D3"
"0004","00000000","00"
"0010","01111100","7C"
"0011","00000001","01"
"0012","00000000","00"
"0013","00000101","05"
"0014","00001000","08"
"0015","00000000","00"
"0016","00000011","03"
"0017","00000000","00"
"0018","00000110","06"
"0019","00000000","00"
"001A","00000000","00"
"001B","00100000","20"
"001C","00000000","00"
"001D","00000000","00"
"001E","00000000","00"
"001F","00001110","0E"
"00A0","00000001","01"
"00A1","00000000","00"
"00A2","00000000","00"
"00A3","00000001","01"
"00A4","00000000","00"
"00A5","00000000","00"
"00A6","00000001","01"
"00A7","00000000","00"
"00A8","00000000","00"
"00A9","00000001","01"
"00AA","00000000","00"
"00AB","00000000","00"
"00F0","00001000","08"
"00F1","00001000","08"
"00F4","00001000","08"
"00F5","00001000","08"
"0140","01000010","42"
"0141","01100010","62"
"0142","01000010","42"
"0143","01010010","52"
"0190","00000000","00"
"0191","10000000","80"
"0192","00000000","00"
"0196","00000000","00"
"0197","00000000","00"
"0198","00000000","00"
"0199","00100010","22"
"019A","00000000","00"
"019B","00010001","11"
"019C","00000000","00"
"019D","00000000","00"
"019E","00100010","22"
"019F","00000000","00"
"01A0","00010001","11"
"01A1","00000000","00"
"01A2","00000000","00"
"01A3","00000000","00"
"01E0","00000000","00"
"01E1","00000010","02"
"0230","00000000","00"
"0231","00000000","00"
"0232","00000000","00"
"","",""
"Other Settings..."
"REF 1:",40
"REF 2:",40
"VCO:",1600
"CLK:",1200
"CPRSet:",5100
"Auto Update:",1
"Load All Regs:",0

  • Hi,

    I loaded the stp file you sent and I found there is a configuration error of the N divider:

    The only way to correct this is to introduce a reference divider equal to 2 and set the N divider to 74. I played with an eval board and I was able to obtain a very good OUT7=30.833MHz by setting the scope input impedance to 50ohm (below).

    I attach the stp file I created: 

    "AD9517 Setup File"
    "Rev.","1.1.0"
    ""
    "Addr(Hex)","Value(Bin)","Value(Hex)"
    "0000","00011000","18"
    "0001","00000000","00"
    "0002","01010000","50"
    "0003","11010011","D3"
    "0004","00000000","00"
    "0010","01111100","7C"
    "0011","00000010","02"
    "0012","00000000","00"
    "0013","00000010","02"
    "0014","00001001","09"
    "0015","00000000","00"
    "0016","00000100","04"
    "0017","10110100","B4"
    "0018","00000111","07"
    "0019","00000000","00"
    "001A","00000000","00"
    "001B","00100000","20"
    "001C","00000010","02"
    "001D","00000000","00"
    "001E","00000000","00"
    "001F","01001111","4F"
    "00A0","00000001","01"
    "00A1","00000000","00"
    "00A2","00000000","00"
    "00A3","00000001","01"
    "00A4","00000000","00"
    "00A5","00000000","00"
    "00A6","00000001","01"
    "00A7","00000000","00"
    "00A8","00000000","00"
    "00A9","00000001","01"
    "00AA","00000000","00"
    "00AB","00000000","00"
    "00F0","00001000","08"
    "00F1","00001000","08"
    "00F4","00001000","08"
    "00F5","00001000","08"
    "0140","01000010","42"
    "0141","01100010","62"
    "0142","01000010","42"
    "0143","01010010","52"
    "0190","00000000","00"
    "0191","10000000","80"
    "0192","00000000","00"
    "0196","00000000","00"
    "0197","00000000","00"
    "0198","00000000","00"
    "0199","00100010","22"
    "019A","00000000","00"
    "019B","00010001","11"
    "019C","00000000","00"
    "019D","00000000","00"
    "019E","00100010","22"
    "019F","00000000","00"
    "01A0","00010001","11"
    "01A1","00000000","00"
    "01A2","00000000","00"
    "01A3","00000000","00"
    "01E0","00000000","00"
    "01E1","00000010","02"
    "0230","00000000","00"
    "0231","00000000","00"
    "0232","00000000","00"
    "","",""
    "Other Settings..."
    "REF 1:",40
    "REF 2:",40
    "VCO:",1480
    "CLK:",1200
    "CPRSet:",5100
    "Auto Update:",1
    "Load All Regs:",1
    
    Just take out the txt extension before loading it into the eval software.

    The schematic you sent does not contain any 50 ohm load on OUT7, which in the stp file was set as LVDS. You set a 51 ohm on the OUT7B. Set the scope with 50 ohm input impedance

    You should obtain the above clock on OUT7.

    Petre