variation of output from 122.88 MHz clock.

Question

Hello there! I am working on AD9523-1 board and from that i want to generate 122.8800 fixed output clock but the poblem is that i configured the o/p of PLL2 is exactly 122.88 i see on frequency counter it is started from 122.8745123 and increasing gradually in Hz and after 2 hours it is increasing from 122.880000 to onwards i mean to say lets suppose after 2 hours it is 122.889909. i need stable clock output which is 122.880000. I have given you the .stp file that i follow as well as i have given you all the configuration screenshoots following that i have changed. Secondly i want to give external refernce frequency by signal generater but it is taking internally guide me how i can give the extertnal frequency. please resolve the problem i want exact stable 122.88 MHz output and if possile give me .stp configuration file i am very thankful to you. Thanks Fullscreen 3364.AD9523_1_setup.stp.txt Download ;Header contains information about the setup file and revision

Product = AD9523-1 FileVersion = 1.0 DecimalSeparator=. ;Used for internationalization

&h0,&b00000001 ;01 Hex, 001 Dec &h2,&b00000000 ;00 Hex, 000 Dec &h3,&b00000000 ;00 Hex, 000 Dec &h4,&b00000000 ;00 Hex, 000 Dec &h5,&b00000000 ;00 Hex, 000 Dec &h6,&b00000000 ;00 Hex, 000 Dec &h10,&b00000001 ;01 Hex, 001 Dec &h11,&b00000000 ;00 Hex, 000 Dec &h12,&b00000100 ;04 Hex, 004 Dec &h13,&b00000000 ;00 Hex, 000 Dec &h14,&b00000001 ;01 Hex, 001 Dec &h15,&b00000000 ;00 Hex, 000 Dec &h16,&b00101000 ;28 Hex, 040 Dec &h17,&b00000000 ;00 Hex, 000 Dec &h18,&b00001100 ;0C Hex, 012 Dec &h19,&b00011111 ;1F Hex, 031 Dec &h1A,&b00010010 ;12 Hex, 018 Dec &h1B,&b00010110 ;16 Hex, 022 Dec &h1C,&b10010000 ;90 Hex, 144 Dec &h1D,&b00000000 ;00 Hex, 000 Dec &h1E,&b00000000 ;00 Hex, 000 Dec &h1F,&b00000000 ;00 Hex, 000 Dec &h20,&b00000000 ;00 Hex, 000 Dec &hF0,&b00000111 ;07 Hex, 007 Dec &hF1,&b10000111 ;87 Hex, 135 Dec &hF2,&b00010011 ;13 Hex, 019 Dec &hF3,&b00000010 ;02 Hex, 002 Dec &hF4,&b01000000 ;40 Hex, 064 Dec &hF5,&b00000000 ;00 Hex, 000 Dec &hF6,&b00000000 ;00 Hex, 000 Dec &hF7,&b00000001 ;01 Hex, 001 Dec &hF8,&b00000000 ;00 Hex, 000 Dec &hF9,&b00000000 ;00 Hex, 000 Dec &hFA,&b00000000 ;00 Hex, 000 Dec &h190,&b01110011 ;73 Hex, 115 Dec &h191,&b00001001 ;09 Hex, 009 Dec &h192,&b00000100 ;04 Hex, 004 Dec &h193,&b00100000 ;20 Hex, 032 Dec &h194,&b00011111 ;1F Hex, 031 Dec &h195,&b00000100 ;04 Hex, 004 Dec &h196,&b01001000 ;48 Hex, 072 Dec &h197,&b00001001 ;09 Hex, 009 Dec &h198,&b00000000 ;00 Hex, 000 Dec &h199,&b01110110 ;76 Hex, 118 Dec &h19A,&b00011111 ;1F Hex, 031 Dec &h19B,&b00000100 ;04 Hex, 004 Dec &h19C,&b01001000 ;48 Hex, 072 Dec &h19D,&b00001001 ;09 Hex, 009 Dec &h19E,&b00000000 ;00 Hex, 000 Dec &h19F,&b00100000 ;20 Hex, 032 Dec &h1A0,&b00011111 ;1F Hex, 031 Dec &h1A1,&b00000100 ;04 Hex, 004 Dec &h1A2,&b00100000 ;20 Hex, 032 Dec &h1A3,&b00011111 ;1F Hex, 031 Dec &h1A4,&b00000100 ;04 Hex, 004 Dec &h1A5,&b00100000 ;20 Hex, 032 Dec &h1A6,&b00011111 ;1F Hex, 031 Dec &h1A7,&b00000100 ;04 Hex, 004 Dec &h1A8,&b01100110 ;66 Hex, 102 Dec &h1A9,&b00001001 ;09 Hex, 009 Dec &h1AA,&b00000100 ;04 Hex, 004 Dec &h1AB,&b01001001 ;49 Hex, 073 Dec &h1AC,&b00001001 ;09 Hex, 009 Dec &h1AD,&b00000000 ;00 Hex, 000 Dec &h1AE,&b01001001 ;49 Hex, 073 Dec &h1AF,&b00001001 ;09 Hex, 009 Dec &h1B0,&b00000000 ;00 Hex, 000 Dec &h1B1,&b01101000 ;68 Hex, 104 Dec &h1B2,&b00001001 ;09 Hex, 009 Dec &h1B3,&b00000100 ;04 Hex, 004 Dec &h1B4,&b01101000 ;68 Hex, 104 Dec &h1B5,&b00001001 ;09 Hex, 009 Dec &h1B6,&b00000100 ;04 Hex, 004 Dec &h1B7,&b01010110 ;56 Hex, 086 Dec &h1B8,&b00001001 ;09 Hex, 009 Dec &h1B9,&b00000000 ;00 Hex, 000 Dec &h1BA,&b00000000 ;00 Hex, 000 Dec &h1BB,&b00000000 ;00 Hex, 000 Dec &h22C,&b00000000 ;00 Hex, 000 Dec &h22D,&b00000000 ;00 Hex, 000 Dec &h22E,&b00000000 ;00 Hex, 000 Dec &h22F,&b00000000 ;00 Hex, 000 Dec &h230,&b00000000 ;00 Hex, 000 Dec &h231,&b00000001 ;01 Hex, 001 Dec &h232,&b00000000 ;00 Hex, 000 Dec &h233,&b00000000 ;00 Hex, 000 Dec &h234,&b00000001 ;01 Hex, 001 Dec &hA00,&b00000000 ;00 Hex, 000 Dec &hA01,&b00000000 ;00 Hex, 000 Dec &hA02,&b00000000 ;00 Hex, 000 Dec &hA03,&b00000010 ;02 Hex, 002 Dec &hA04,&b00000000 ;00 Hex, 000 Dec &hA05,&b00000100 ;04 Hex, 004 Dec &hA06,&b00001110 ;0E Hex, 014 Dec &hA07,&b00000000 ;00 Hex, 000 Dec &hA08,&b00010000 ;10 Hex, 016 Dec &hA09,&b00001110 ;0E Hex, 014 Dec &hA0A,&b00000000 ;00 Hex, 000 Dec &hA0B,&b11110000 ;F0 Hex, 240 Dec &hA0C,&b00101011 ;2B Hex, 043 Dec &hA0D,&b00000001 ;01 Hex, 001 Dec &hA0E,&b10010000 ;90 Hex, 144 Dec &hA0F,&b00000001 ;01 Hex, 001 Dec &hA10,&b00000001 ;01 Hex, 001 Dec &hA11,&b11100000 ;E0 Hex, 224 Dec &hA12,&b00000011 ;03 Hex, 003 Dec &hA13,&b00000010 ;02 Hex, 002 Dec &hA14,&b00110000 ;30 Hex, 048 Dec &hA15,&b10000000 ;80 Hex, 128 Dec &hA16,&b11111111 ;FF Hex, 255 Dec &hB00,&b00000000 ;00 Hex, 000 Dec &hB01,&b00000000 ;00 Hex, 000 Dec &hB02,&b00000000 ;00 Hex, 000 Dec &hB03,&b00000000 ;00 Hex, 000 Dec PortA=&h1E ;Bit0=USBStatus, Bit1=CSB, Bit2=ResetB, Bit3=SyncB, Bit4=PDB, Bit5=RefSel AutoSendUpdate=1 ;AutoIOUpdate Setting REF_A = 10.0000 REF_B = 10.0000 REF_TEST = 10.0000 VCXO = 100.0000

pminc48 · Accepted Answer

HI, I'm sorry, but the file you send does not match the photos from your enquiry. Loading the stp file I get this: I suppose you have an eval board and I'll create a stp file that could be run on the eval board. I'll also use some information from your photos. You should apply 30.72 MHz, 3 dBm from a signal generator at REFA, J9 connector. Fullscreen AD9523_1_setup_Petre.stp.txt Download ;Header contains information about the setup file and revision

Product = AD9523-1 FileVersion = 1.0 DecimalSeparator=. ;Used for internationalization

&h0,&b00000000 ;00 Hex, 000 Dec &h2,&b00000000 ;00 Hex, 000 Dec &h3,&b00000000 ;00 Hex, 000 Dec &h4,&b00000000 ;00 Hex, 000 Dec &h5,&b00000000 ;00 Hex, 000 Dec &h6,&b00000000 ;00 Hex, 000 Dec &h10,&b00000000 ;00 Hex, 000 Dec &h11,&b00000000 ;00 Hex, 000 Dec &h12,&b00000000 ;00 Hex, 000 Dec &h13,&b00000000 ;00 Hex, 000 Dec &h14,&b00000000 ;00 Hex, 000 Dec &h15,&b00000000 ;00 Hex, 000 Dec &h16,&b00000100 ;04 Hex, 004 Dec &h17,&b00000000 ;00 Hex, 000 Dec &h18,&b00001100 ;0C Hex, 012 Dec &h19,&b00000011 ;03 Hex, 003 Dec &h1A,&b00101010 ;2A Hex, 042 Dec &h1B,&b00010000 ;10 Hex, 016 Dec &h1C,&b00000000 ;00 Hex, 000 Dec &h1D,&b00000000 ;00 Hex, 000 Dec &h1E,&b00000000 ;00 Hex, 000 Dec &h1F,&b00000000 ;00 Hex, 000 Dec &h20,&b00000000 ;00 Hex, 000 Dec &hF0,&b11111111 ;FF Hex, 255 Dec &hF1,&b00000110 ;06 Hex, 006 Dec &hF2,&b00000011 ;03 Hex, 003 Dec &hF3,&b00000000 ;00 Hex, 000 Dec &hF4,&b01000000 ;40 Hex, 064 Dec &hF5,&b00000000 ;00 Hex, 000 Dec &hF6,&b00000000 ;00 Hex, 000 Dec &hF7,&b00000000 ;00 Hex, 000 Dec &hF8,&b00000000 ;00 Hex, 000 Dec &hF9,&b00000000 ;00 Hex, 000 Dec &hFA,&b00000000 ;00 Hex, 000 Dec &h190,&b00000000 ;00 Hex, 000 Dec &h191,&b00000111 ;07 Hex, 007 Dec &h192,&b00000100 ;04 Hex, 004 Dec &h193,&b00100000 ;20 Hex, 032 Dec &h194,&b00011111 ;1F Hex, 031 Dec &h195,&b00000100 ;04 Hex, 004 Dec &h196,&b00000000 ;00 Hex, 000 Dec &h197,&b00011111 ;1F Hex, 031 Dec &h198,&b00000100 ;04 Hex, 004 Dec &h199,&b00000100 ;04 Hex, 004 Dec &h19A,&b00000111 ;07 Hex, 007 Dec &h19B,&b00000100 ;04 Hex, 004 Dec &h19C,&b00000000 ;00 Hex, 000 Dec &h19D,&b00011111 ;1F Hex, 031 Dec &h19E,&b00000100 ;04 Hex, 004 Dec &h19F,&b00100000 ;20 Hex, 032 Dec &h1A0,&b00011111 ;1F Hex, 031 Dec &h1A1,&b00000100 ;04 Hex, 004 Dec &h1A2,&b00000000 ;00 Hex, 000 Dec &h1A3,&b00011111 ;1F Hex, 031 Dec &h1A4,&b00000100 ;04 Hex, 004 Dec &h1A5,&b00100000 ;20 Hex, 032 Dec &h1A6,&b00011111 ;1F Hex, 031 Dec &h1A7,&b00000100 ;04 Hex, 004 Dec &h1A8,&b00000000 ;00 Hex, 000 Dec &h1A9,&b00011111 ;1F Hex, 031 Dec &h1AA,&b00000100 ;04 Hex, 004 Dec &h1AB,&b00100000 ;20 Hex, 032 Dec &h1AC,&b00011111 ;1F Hex, 031 Dec &h1AD,&b00000100 ;04 Hex, 004 Dec &h1AE,&b00000000 ;00 Hex, 000 Dec &h1AF,&b00011111 ;1F Hex, 031 Dec &h1B0,&b00000100 ;04 Hex, 004 Dec &h1B1,&b00100000 ;20 Hex, 032 Dec &h1B2,&b00011111 ;1F Hex, 031 Dec &h1B3,&b00000100 ;04 Hex, 004 Dec &h1B4,&b00000000 ;00 Hex, 000 Dec &h1B5,&b00011111 ;1F Hex, 031 Dec &h1B6,&b00000100 ;04 Hex, 004 Dec &h1B7,&b00100000 ;20 Hex, 032 Dec &h1B8,&b00000111 ;07 Hex, 007 Dec &h1B9,&b00000100 ;04 Hex, 004 Dec &h1BA,&b00000000 ;00 Hex, 000 Dec &h1BB,&b10000000 ;80 Hex, 128 Dec &h22C,&b00000000 ;00 Hex, 000 Dec &h22D,&b00000000 ;00 Hex, 000 Dec &h22E,&b00000000 ;00 Hex, 000 Dec &h22F,&b00000000 ;00 Hex, 000 Dec &h230,&b00000000 ;00 Hex, 000 Dec &h231,&b00000000 ;00 Hex, 000 Dec &h232,&b00000000 ;00 Hex, 000 Dec &h233,&b00000000 ;00 Hex, 000 Dec &h234,&b00000000 ;00 Hex, 000 Dec &hA00,&b00000000 ;00 Hex, 000 Dec &hA01,&b00000000 ;00 Hex, 000 Dec &hA02,&b00000000 ;00 Hex, 000 Dec &hA03,&b00000010 ;02 Hex, 002 Dec &hA04,&b00000000 ;00 Hex, 000 Dec &hA05,&b00000100 ;04 Hex, 004 Dec &hA06,&b00001110 ;0E Hex, 014 Dec &hA07,&b00000000 ;00 Hex, 000 Dec &hA08,&b00010000 ;10 Hex, 016 Dec &hA09,&b00001110 ;0E Hex, 014 Dec &hA0A,&b00000000 ;00 Hex, 000 Dec &hA0B,&b11110000 ;F0 Hex, 240 Dec &hA0C,&b00101011 ;2B Hex, 043 Dec &hA0D,&b00000001 ;01 Hex, 001 Dec &hA0E,&b10010000 ;90 Hex, 144 Dec &hA0F,&b00000001 ;01 Hex, 001 Dec &hA10,&b00000001 ;01 Hex, 001 Dec &hA11,&b11100000 ;E0 Hex, 224 Dec &hA12,&b00000011 ;03 Hex, 003 Dec &hA13,&b00000010 ;02 Hex, 002 Dec &hA14,&b00110000 ;30 Hex, 048 Dec &hA15,&b10000000 ;80 Hex, 128 Dec &hA16,&b11111111 ;FF Hex, 255 Dec &hB00,&b00000000 ;00 Hex, 000 Dec &hB01,&b00000000 ;00 Hex, 000 Dec &hB02,&b00000000 ;00 Hex, 000 Dec &hB03,&b00000000 ;00 Hex, 000 Dec PortA=&h1E ;Bit0=USBStatus, Bit1=CSB, Bit2=ResetB, Bit3=SyncB, Bit4=PDB, Bit5=RefSel AutoSendUpdate=1 ;AutoIOUpdate Setting REF_A = 30.7200 REF_B = 30.7200 REF_TEST = 10.0000 VCXO = 122.880 I created the attached. I did not test it on an eval board, but it should work. It creates at OUT3 122.88MHz, HSTL driver as you seem to want. If you apply the REFA clock as indicated above and you calibrate the PLL2 VCO correctly, the AD9523-1 should generate exact 122.88MHz clock. Petre)

pminc48 · Answer

Hi, 
 not clear to me what the question is. 
 You configured the AD9523-1 to receive 30.72MHz clock and output 122.88MHz clock. If the reference is out by 2ppm, the output will be out by 2 ppm. 
 You would like the AD9523-1 output to remain unchanged. This is not how this chip works. I responded to a similar question here: 
 Output frequency should be constant and VCXO should be auto adjustable 
 Petre

pminc48 · Answer

Hi, 
 I already told you the solution: change the reference clock source to be stable over temperature. If you change the reference clock within a certain tolerance, like your 2ppm, the output will change by 2 ppm. There are digital PLL devices that when the reference clock goes outside an user selected tolerance, the device considers it invalid, sets the DPLL in holdover and continues to generate the desired exact output clock. Look at the AD9542, procure an eval board and play with it. 
 Petre

Abdul202020 · Answer

pminc48 said: Hi, 
 
 Thanks for your help and suggestion.

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variation of output from 122.88 MHz clock.

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