What loop filter design tool should I use for LTC694x PLLs and PLL/VCOs?
The short answer is:
LTC6945, LTC6946: PLLWizard
LTC6948: Either FracNWizard or ADIsimPLL
ADIsimPLL (https://form.analog.com/Form_Pages/RFComms/ADISimPll.aspx )
PLLWizard (http://swdownloads.analog.com/pllwizard/pllwizardsetup.exe )
FracNWizard (http://swdownloads.analog.com/fracnwizard/fracnwizardsetup.exe )
The long answer is:
Since 2002 ADI has used ADIsimPLL for loop filter design and simulation for the full catalog of PLLs, VCOs, and PLL/VCOs. When ADI acquired Linear Tech in 2017, Linear Tech had four released PLL/VCO parts that used Linear Tech developed loop filter design and simulation tools (PLLWizard and FracNWizard). Since these Linear Tech tools also functioned as the software GUI to control the evaluation hardware, these tools are still supported. We plan to add loop filter design simulation for all LTC694x parts into ADIsimPLL. However, only the LTC6948 has been added to ADIsimPLL, as of September 2018. One nice feature ADIsimPLL has, that was missing in the Linear Tech tools, is time domain simulation for loop settling times.
And for those people who, like me, just love spreadsheets… here is a quick comparison
We are planning to use your LTC6948 PLL for our application and as per your above statement, Either FracNWizard or ADIsimPLL both will support for Loop filter design of LTC6948 PLL.
But we have installed latest ADIsimPLL_V5_0_03 software and we are unable to find LTC6948 in Chip list.
Also we have installed FracNWizard and unable to find user guide for step-by-step configuration of our inputs and simulation for our requirement.
Please share if your have updated ADIsimPLL version which supports LTC6948 or Share the FracNWizard user guide.
Hi, Apologize about that, the next ADIsimPLL version with the LTC6948 should have been released already. Its coming soon. The FracNWizard has a Help Guide under 'Help' (on the top FracNWizard tool bar).
I put this pdf together that gives a quick example of how to design a loop filter and simulate its phase noise. Also, under File, there is away to upload your input reference noise. I've included a text file here to show you the format needed for importing reference noise.
SIMULATING PHASE NOISE WITH FRACNWIZARD.pdf
#Offset Frequency (Hz) Phase Noise (dBc/Hz)
Thanks for your FracNWizard user guide.
When can I expect the next released ADIsimPLL version with LTC6948? Because I am more familiar using and designing ADIsimPLL tool.
Maybe 2 weeks? The FracNWizard tool it pretty easy to use, once you get used to it. I can give a quick 15 minute demonstration if you would like. What time zone are you in? I can set up a skype meeting...