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Queries about ADF4351 Fast Locking

Question asked by WayneQ on Jun 25, 2014
Latest reply on Jul 1, 2014 by icollins

Hi, there


Good Day!

I have two questions about ADF4351 fast locking and need your help.


1, as mentioned in the section of FAST LOCK EXAMPLE in the datasheet,

Fast Lock Timer Value = (VCO Band Select Time + PLL Lock Time in Wide Bandwidth) × f PFD /MOD

in my application, the frequency will work and hop in Integer-N mode, how could I set MOD value in above function? is "1" ok?


2, also in this section, the example gives lock time of 60us. But in the function,

VCO Band Select Time = 20us

PLL Lock Time in Wide Bandwidth = 20us

what does PLL Lock Time in Wide Bandwidth mean? and what does the rest 20us (60us - 20us - 20us) stand for?


Appreciate for your kindly help and guide here!