Ad9122 data input

1、Do N data input port and P data input port of ad9122 control IOUTN and IOUTP respectively?

2、Is the IQ signal to be set up separately in FPGA, or only one channel of data will be created, and the data will be automatically divided into I channel and Q channel  in the chip?

3、If I use stm32f4 Series MCU with 168mhz clock frequency instead of FPGA, can I output 150MHz sine wave with AD9122?

Because I'm a beginner, I don't know many things. I may ask some low-level questions. Please forgive me.Thank you for your answer.

Parents Reply Children
  • +1
    •  Analog Employees 
    on Mar 17, 2021 2:21 AM in reply to Tianxunna

    Hi Tianxunna, 

    some comments as,   

    1,  the IOUTN and IOUTP is the differential DAC  output.  it is the output of converted digital data. 

    2,  I/Q data are the signal generated by  customer in their digital backend, 

    3,  AD9122 is taking the role of converting the data ,which feed in through the LVDS  digital interface.  if you want  150Mhz sinewave output,  your  DAC rate should  > 300Mhz  to have sinewave output at 1st nyquist zone.

  • Thank you ,I understand the previous question.But now I have some new questions.

    1、My output is SMA interface. How to use oscilloscope to measure output?

    My current situation is that I directly connect iout-p and iout-n to the oscilloscope without any processing, and the output is always 3.3V. But I have created a sine wave in FPGA and driveit to ad9122 through LVDS  interface.For register configuration, I refer to page 59 of the datasheet.

    I hope and look forward to your answers,thank you!