• AD6644: Vref load current

    He wants to know, how accurate the internal reference from the AD6644 is, and
    how much current it can drive. He wants to use it for other parts, too.
    Therefore he needs a current of 100uA out of the internal reference. Is this
  • AD6644: Eval Board usage

    I have recently purchased the 6620 and it's ev board and I am
    having some problems getting it to work! I am using the 6644 ADC
    and it's ev board so it just plugs straight in. The jumper (99)
    is connected, the 6644 has a 5V supply…
  • AD6644: Decoupling/grounding recommendations

    We are using an AD6644 ADC. The data sheet does not stated which GND pins
    are associated with the
    analogue or the digital sections. Please can you tell me.
    Furthermore, could you send any PCB layout/Grounding recommendations when
  • AD6644 - Variable clock frequency

    Hi there,

    I have a question regarding the AD6644 converter. Is it possible to use it with a clock whose frequency varies? Can the device work under this operating condition and what would the max conversion rate be?

    I am available for a private discussion…

  • RE: FPGA Reference Design for AD6644/AD6645 and AD9764 Data Converters


    AD6644-45 does not have SPI control pins. Is it enough Tto sample data when ENCODE is LOW and DRY is HIGH as stated in my second reply ?


  • RE: AD9764 clock input and COMP2 voltage

    Hi Mr. Larry -

    Thank you very much for your reply .

    Can I directly connect the FPGA clock signal output which is 6.6V pk-pk 1.75 Vmean 16 MHz square wave signal ? In the 4th page of AD6644 datasheet it is ENCODE inputs are 0.4V pk-pk differential input…

  • Minimum Frequency of Inputs for AD9214 and AD6644

      Good morning.  I have a customer inquiring as to how low the freqeuncy of a signal can be to drive the analog inputs of the AD9214-105 and the AD6644-65.  He needs to be able to accommodate some signals that will be in the range from 50KHz - 100KHz.

  • RE: AD9764 output

    Hi Mr. Larry Welchusa

    Thank you very much for your help

    I attached the schematic pdf file. I can also send the layout files' pictures.

    In addition to the schematic i have made two differences in the layout. The first one is adding two capacitors…

  • AD6645: Selection of resistor values

    In the EVM you use two banks of resistor before and after the latches. Does the
    board work with values between 33 and 47 ohm for RN1 and RN3?


    The board will be functional with all values of resistors up to the 470ohms.
    The higher resistance…
  • Weak signal at the DAC input

    Hi everybody ,

    I have created my own DAQ board using AD6644 and AD9764 as indicated in their evaluation boards' document.

    I want to ask some questions :

    1) The Vref supply does not source current after the AVCC is connected is it OK ?

    2) Is there…