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ADF4002 PFD noise floor at higher offsets?

Question asked by deltapapat65d on Dec 15, 2015
Latest reply on Dec 17, 2015 by rbrennan

The data sheet specifies a normalized PFD noise floor of -222 dBc/Hz.

This is specified for a PLL BW = 500 kHz measured at 100 kHz offset on page 4 of the data sheet.

However, what is the noise floor at higher offsets, such as 500 kHz, 1 MHz, or 2 MHz?

Does it remain more or less "flat" at higher offsets, once past the 1/f roll-off.

Also, would the PFD frequency have any effect other than the expected 10 LOG Fpd change?

I am especially interested in the behavior at higher offsets, with the PFD running at 50 or 100 MHz.

I assume that this question is relevant for many of the ADF4xxx parts, which seem to share many common components.

Thank you.

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