ADF4155: LDC - INT, FRAC, MOD, and R Counter Relationship

What is the meaning of channel spacing frequency? Can you explain it in detail? How do I know the channel spacing of my designed system?



  • +1
    •  Analog Employees 
    on Jun 4, 2020 7:22 AM 8 months ago

    Hi Wallace,

    Channel spacing is a way to calculate common MOD2 value if multiple output frequencies is desired with fractional operation.

    If you want single frequency output, then you can calculate the MO2 and FRAC2 values with minimum values gives the remainder that you need as given in the example calculation in Page 26 of datasheet. Channel spacing is not required for single frequency calculations

    If your output frequency is an integer multiple of PFD frequency, then you just need to set INT value and 0 for the rest.