[time-nuts] Digital PLL ICs,alternatives and digital loop filters

[Stephan Sandenbergh]

Hi all,

 

Thanks for all of the very helpful responses, links and advice. I'm very
sorry that I couldn't participate in the discussion at the time but I was a
bit under resourced on e-mail facilities during the festive season.

 

The trend that I noted from your replies is that the different techniques
for up-converting from 10MHz to 100MHz can be ranked as follows: (best noise
performance first)

 

1.	Pure Analogue PLL where two high quality OCXOs are slaved onto
another. 
2.	Analog frequency multipliers (if the reference is of low enough
phase noise)
3.	Digital PLL

 

This list is also, as expected, ranked in order of associated cost. 

 

My GPS disciplined 10MHz OCXO, an Oscilloquartz model 8788 has the following
phase noise:

 

1Hz      -100 dBc

10Hz     -130

100Hz   -152

1kHz     -160

10kHz   -165

100kHz -165

1MHz    -165