Reading the AD5696R

I am investigating a problem we are having with reading from the AD5696R. When following the "read operation" procedure, the value returned is nearly always 0x91. I attached a Corelis BusPro-I I2C monitor to the EVAL-AD5696RSDZ and performed a read, and noticed that it did not seem to be following the procedure. When reading from DAC C, the command following the first address byte was 14, not 04 as I understood from the datasheet. Can you explain why I am seeing a different read operation than is described in the datasheet? 

  • 0
    •  Analog Employees 
    on Mar 7, 2018 7:03 PM

    Hi Kevin,

    Can you provide the datecode of the AD5696R you are using? Thanks

    Cheers,

    Ivan

  • Neither the ACE software or the datasheet happen to mention a datecode. The AD5696R on my EVAL-AD5696RSDZ has the letters BRUZ and a #713. It will require considerably more effort to get at the AD5696R we are using in our application.

  • 0
    •  Analog Employees 
    on Mar 8, 2018 2:48 PM

    Hi Kevin,

    Unfortunately we need the datecode (i.e. #713) of the AD5696R which you had problems in communicating using the Corelis.

    Cheers,

    Ivan

  • 0
    •  Analog Employees 
    on Mar 8, 2018 7:52 PM

    Hi,

    the date code #713 refers to a unit before the device was fixed.

    http://www.analog.com/media/en/PCN/ADI_PCN_16_0138_Rev_-_Form.pdf 

    This may explain why you cannot communicate with the device.

    The faster option to get latest silicon is by requesting samples thru the ADI web page.

    Answering your question, the DS recommends a NOP command BUT, as the command is just to point to the register, and the restart condition aborts the command, the command transmitted is irrelevant.

    Best Regards,

    Miguel

  • Because I observed a problem in my application, I attached a Corelis to a EVAL-AD5696RSDZ in order to observe its operation and see how my attempted reads differ from EVAL-AD5696RSDZ successful reads. So far, I am able to write but unable to read with the Corelis. Also, I have observed that EVAL-AD5696RSDZ reads use a "write" command(0x1) while reading even though the datasheet specifies "NOP" (0x0).

     

    I hope to learn how to control the AD5696R on my EVAL-AD5696RSDZ using my Corelis. If this succeeds, I will attempt to control the AD5696R in my application the same way. So, the problem in front of me right now is my AD5696R with date code #713.

    above, the Corelis monitoring the EVAL-AD5696RSDZ read of DAC B. Below, the Corelis tries reading DAC B.