• Question about AD9958

    Hi. I use SPI communication to control the AD9958. Is it possible to read the value in the I/O port buffer before transferring the data to the register?
    I hope to hear your response. Thank you.


    【Detailed Block Diagram】


    AD9958 / PCBZ

  • AD9958 - Minimum time after MRST

    On the AD9958, what is the minimum time allowed after MRST goes low before SPI communications can begin and function as normal? I think I am not waiting long enough on my part and it is affecting the performance. Right now there is a 10ns gap between…

  • AD9958 Evaluation board for RF signal generation

    Hello everyone,I am a PhD student and I am looking for a solution to replace a DDS-based RF signal generator (AD9958) on a homemade evaluation board with a similar commercial one.  Specifically, I need a generator that creates an RF signal characterised…

  • AD9958: Timing of SCLK for a data read operation

    Datasheet says that data is read at the falling edge of SCLK, but the timing
    diagrams are very unclear. The falling edges do not point to the read data bits
    properly. In table 25, the minimum data valid time is denoted to be 12ns (must
    that be…

  • AD9958: Communication and PWR_DWN_CTL

    I have a question regarding fast recovery power-down mode and the PWR_DWN_CTL bit for the AD9958

    When placing this device in power down mode using the external bit, am I still able to update the internal registers via SPI bus? And use IO Update to store…

  • AD9958: IO_UPDATE overlap with CS

    I have a question regarding the behavior of IO_UPDATE with the timing of an SPI transaction.

    Here's the scenario:

    Let's say I program in a linear sweep to the DDS, then pulse the update. Immediately after, I program in another linear sweep, but do…

  • AD9958 - Can't write to registers - keeping their default values/some other value

    I have an AD9958 installed on a custom PCB, and I am running into a problem with communication with the part. Registers 0, 1, and 2 can be written to, read from, and changed, and I can see their effects on the part from a scope (can change SYNC_CLK speed…

  • AD9958 loop_filter components

    Hi all,

    Our customer will design the custom board with AD9958.

    They have the question about the Loop_Filer, 27pin.

    @ the datasheet rev.c,
    27 pin description ;
    Connects to the external zero compensation network of the PLL loop filter.
    Typically, the network…

  • AD9958- Linear Sweep and Phase Modulation

    I am using the AD9958 to conduct a linear sweep, using P2 and P3 to toggle the sweep up and sweep down of said sweep.

    However, I would also like to use the phase modulation capabilities of this part to swap the phase 180 degrees at the peaks of my sweeps…