• AD9549 no PLL lock


    I am using an AD9549 on our own board:

    • 10 MHz Input on REFA
    • 10 MHZ (XO) Input for SysCLK
    • 1 GHz SysCLK
    • 10 MHZ Output

    I start with the single tone mode (which works fine) and change to closed loop after a valid signal is detected on…

  • AD9549 programing sequence

    Hi all.

    My customer ask me about  AD9549 programing sequence.

    His questions are following,

    After setting following sequence A, it hapenns frequently that signal is not output at pin 34,35 and 38.

    【Sequence A】
    1. 0000h 98h write  change to 4-wire serial…

  • AD9549 REFx_IN duty cycle

    HI all,

    What is the duty cycle of REFx_IN @ AD9549?

    It is 45(min), 55(max) % ?

    Or varaety duty cycle is avalable ?

    For example, Hi 10% Low 90% ?

    Best regards,


  • Lock time reduction in AD9549


    My customer used AD9549 in holdover mode.

    She wants to reduce the re-locking time of AD9549 when REF_IN was supplied again after that did not been for a while.

    1. Could you recommend a method to reduce the re-locking time in AD9549 except for changing…

  • AD9547, AD9548, AD9549 EV-Boards


    I have a few questions regarding the AD954x Evaluation boards.

    1. Can the AD9548 EV-board be used to evaluate the performance of the AD9547 provided reference is >1kHz and I/O's are limited to the number available on the AD9547? (We do have a few…

  • Switch reference clock input of AD9549


    I am trying to switch the reference clock input from REF_B to REF_A, but the chip continues locking with the REFA Clock.

    The registers have been set with these values below.

    Reg : Value

    0100 : 30 -- enable single tone, close loop off


  • RE: AD9912 eval board firmware source code

    Hi Jim,

    The AD9912 is a derivative of the AD9549. The AD9912 is DDS function in the AD9549.

    I have attached the firmware and source code for the AD9549 evaluation board software. So, it's

    for the AD9912 too.

  • AD9547/8/9 Drift in holdover

    How much drift do the AD9547, AD9548, and AD9549 devices exhibit when in holdover mode?

  • RE: Hope to provide the firmware source for AD9518-0

    I used the Evaluation Board AD9518-0 the principle circuit, I want to produce a two-way 600MHz clock signal.

    The circuit board is designed based on evaluation board.

    The absence of the firmware, I the AD9549 firmware.

    Through several tests to find…

  • AD9912 evaluation board -- Cypress EZ-USB FX2 (68613) - EEPROM missing


    I have an AD9912 evaluation board which when connected via USB to the computer shows up as "Cypress EZ-USB FX2 (68613) - EEPROM missing". This board is then not recognized by the AD control software. I have another identical evaluation board with…