• ADF4108S

    Hi all,

    I am currently looking for a complete PLL for a space application and the phase comparator ADF4108S may be a good option.

    On the main page of the component, the discussion section refers to the ADF4108, is it the equivalent of the ADF4108 in…

  • ADF4108 PLL design

    Dear Team,

    Currently, we are developing the prototype for the space grade frequency synthesizer using ADF4108 which is the commercial equivalent of ADF4108S. We have bought the ADF4108 Eval Board and tested the synthesizer output as per our configuration…

  • ADF4108 RF input

    Does RFIN(A) need to be DC blocked (AC coupled)?  The datasheet states: This small signal input is ac-coupled to the external VCO.  Does this mean that the ADF4108 is internally ac-coupled?  Or is the expectation that the input pin needs to be ac-coupled…

  • ADF4108 Jitter Issue

    I am trying to resolve a jitter/FM issue with a set of frequency up and down converters.  Each of these converters use "2" separate ADF4108's to phase lock VCO's in a dual conversion heterodyne process.  The VCO's are used as Local Oscillators…

  • ADF4108 Not Locking

    Hi Everyone,

    I'm testing my ADF4108 based design, I am using a Synergy Microwave VCO that works up to 8GHz and I want to generate signals in the frequency range near 7400 MHz.

    I am using a 20 MHz TCXO as a REF_IN clock and a passive filter loop designed…

  • ADF4108 Eval Board filter


    The datasheet for the ADF4108 eval board shows a schematic, but the schamic is using the ADF4107. It shows placeholders for values for the loop filter. The Bill of material shows values - but is it correct for the DF4108 or for the ADF4108.


  • ADF4108 REFin Characteristic Question

    Hi I have a question regarding ADF4108 REFin since I assumed that it can handle 10 MHz without additional requirements. I have since found out from the datasheet of the ADF4108 that for a 10 MHz REFin input, the Slew Rate must be greater than 50V/uS.

  • ADF4108 Power Supply

    What are the real effects of AVdd and DVdd moving by more than ±2%?  There doesn't appear to be anything in the data sheet that plots the output over supply.



  • ADF4108 RF Input Sensitivity

    Hi. I am planning to use an ADF4108 for my PLL design. However I am confused by its maximum value of RF Input Sensitivity. From my understanding, according to the datasheet, the max power I can feed back from the VCO is +5 dBm. However, in the hardware…

  • testing ADF4108 evaluation board

    Hi all.

    I bought ADF4108 evaluation board, and I want to test it. I am new to this topic so I would love to see detailed help. I have a lab osccilator that can generate a pulse of  frequency upto 2MHz only. And I have a spectrum analyzer up to 3GHZ only…