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ADF4351  Band select clock frequency

Question asked by Tak-8810 on Sep 24, 2013
Latest reply on Oct 2, 2013 by icollins

I have question about band select clock of ADF4351.
There is a description of the following in the data sheet.

 

Datasheet Page.13
If faster lock times are required, Bit DB23 in Register 3 (R3) must be set to 1.
This setting allows the user to select a higher band select clock frequency of up to 500 kHz,
which speeds up the minimum band select time to 20 μs.

 

Datasheet Page.19
Setting the DB23 bit to 0 is recommended for low PFD (<125 kHz) values.

 

So, I understood as below.
・In non-faster band select mode(RB23 set to 0), bandselect clock frequency recommends less than 125kHz.

・In faster band select mode(RB23 set to 1), bandselect clock frequency supports up to 500kHz.

 

If these understanding is correct, is it problem that I use band select clock greater than 125kHz in non-faster band select mode?
(The problems which I have said are an oscillation, degradation of CN, and others. )

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