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Simulators >> RF Simulators >> pll simulation using phase domain models
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Message started by chenyan on Mar 31^st, 2008, 2:03am

Title: pll simulation using phase domain models
Post by chenyan on Mar 31^st, 2008, 2:03am

Hi all,

I am new to verilog-A simulation of pll. When I read Ken's "Predicting the phase noise and jitter of pll-based frequency synthesizers", in the VCO model

Theta(out)<+2*'M_PI*gain*idt(V(in))

So here the Theta(out) will increase infinitely unless V(in) is zero, then small signal simulatoin doesnot work, how can I solve this problem?

Another question is, I converted all the simulated block phase noise (dBc/Hz) into "power" by 10^(L/10) and then input them into noise table, is that the right way to do it?

Thanks a lot
chenyan

Title: Re: pll simulation using phase domain models
Post by pancho_hideboo on Mar 31^st, 2008, 7:39am

rfmems wrote on Mar 31^st, 2008, 2:03am:

Use "idtmod()".

rfmems wrote on Mar 31^st, 2008, 2:03am:

Another question is, I converted all the simulated block phase noise (dBc/Hz) into "power" by 10^(L/10) and then input them into noise table, is that the right way to do it?

Maybe it works.

Title: Re: pll simulation using phase domain models
Post by chenyan on Apr 1^st, 2008, 12:10am

Thanks a lot! pancho_hideboo.

Yes, I think idtmod will work, but we have to do pss+pnoise right? And we will use again 2 frequencies, one reference and one vco.

But Ken mentioned with phase domain models, using only small signal simulation like AC or noise will do. Would there be an alternative way to do so?

Title: Re: pll simulation using phase domain models
Post by pancho_hideboo on Apr 1^st, 2008, 12:41am

rfmems wrote on Apr 1^st, 2008, 12:10am:

Thanks a lot! pancho_hideboo.
Yes, I think idtmod will work, but we have to do pss+pnoise right? And we will use again 2 frequencies, one reference and one vco.
But Ken mentioned with phase domain models, using only small signal simulation like AC or noise will do. Would there be an alternative way to do so?

Although I don't know what you like to do, the following might be helpful.
$CDS_INST_DIR/tools/dfII/samples/artist/rfLib/osc

Do you understand phase model and voltage model ?