What's the frequency of carrier frequency provided by AD9862 for digital up conversion?


    I'm a student,our lab is studying USRP recently.I know AD9862 in USRP have the function of digital up conversion.Would you tell me how big the carrier frequency is?Is it a constant or range?I havn't found the answer in AD9862's datasheet.

   Thank you!   

  • 0
    •  Analog Employees 
    on Jul 2, 2012 8:14 AM


    This has been moved from the Hardware Tools community to the High-Speed DACs community. Please continue the discussion here.



  • 0
    •  Analog Employees 
    on Jul 2, 2012 6:03 PM

    The AD9862 digital data path supports complex or real modulation which is what the data sheet means by digital up convertion. The details of the modulation is described on pages 19 and 20 of the data sheet. There is coarse modulation that will mix the signal upto 1/8 or 1/4 FDAC where FDac is the DAC sample rate frequency. There is also a 24 bit NCO that offers fine resolution of the modulation up to 1/4 FDAC, which has to be used with the 4x interpolation mode. Since the DACs max sample rate is 128MSPS the maximum frequency you can mix up to is 32MHz. With the NCO the mixing frequency can be DC to 32MHz. The desired frequency is set with the regsiters that set frequency tunning word of the NCO.

                   Best Regards