AD9552 loop bandwidth and PFD rate?

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Accepted Answer

Question Would you please tell me the bandwidth of the Loop Filter? And if the PD(Phase 
 detect) Frequency is 10kHz, AD9552's output is 300kHz or 3MHz, then how about 
 the spur performance of the output? Answer The AD9552 loop bandwidth is 50KHz. The charge pump current is linked to the N 
 feedback divider division value so when the N division is changed the charge 
 pump current is changed by the same percentage to maintain constant bandwidth.
 The PFD rate is the reference input frequency or 2x if the doubler is turned 
 on. If the input frequency is below 16MHz (by selecting A2:A0) the doubler 
 will automatically turn on.
 We don’t have a guaranteed spurious spec in the tables. With a fractional PLL 
 with a lot of flexibility it is difficult to do this. There could be more than 
 one configuration that can achieve the same output frequency, often I suggest 
 to try them to see which gives the desired spurious performance.

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AD9552: FAQ