# calculation and plot of phase noise for phase frequency detector in cadence

1. ## calculation and plot of phase noise for phase frequency detector in cadence

Hi all,

I am trying to find how to find phase noise for phase frequency detector in PLL in cadence.
Everyone is discussing about phase noise in VCO.
Please any one can help me in finding phase noise value and plot in cadence.

Regards,
tanya dey

•

2. ## Re: calculation and plot of phase noise for phase frequency detector in cadence

Perhaps you can find the info here: pss_and_phase_noise_analylsis_of_oscillators_in_cadence_171.pdf

If this is not enough, try one of these links.

1 members found this post helpful.

•

3. ## Re: calculation and plot of phase noise for phase frequency detector in cadence

1 members found this post helpful.

•

4. ## Re: calculation and plot of phase noise for phase frequency detector in cadence

Originally Posted by erikl
Perhaps you can find the info here: pss_and_phase_noise_analylsis_of_oscillators_in_cadence_171.pdf

If this is not enough, try one of these links.

do u know how to plot phase sentivity and phase difference in cadence?

5. ## Re: calculation and plot of phase noise for phase frequency detector in cadence

If you use Cdence APS, I recommend you to use Shooting-PSS/FullSpectrum-Pnoise.
See http://www.designers-guide.org/Forum...1438976388/2#2

do u know how to plot phase sentivity and phase difference in cadence?
It's very easy.

See page-36 in the following.
http://een.iust.ac.ir/profs/Abrisham...20HspiceRF.pdf

Assume PFD have two inputs, ref_clk and fb_clk.

Sweep phase difference between ref_clk and fb_clk in PSS.
And then plot real part of zero order harmonics of current flowing to load voltage source which is biased at typical vcontrol voltage for VCO.
Next apply deriv() to Icp v.s. delta_phi.

The following is a case of Synopsys HSPICE.
However it can be same as Cadence Spectre.

The followings are general notes for you.

- Don't use unfamiliar abbreviations such as "U R right", "Do U", "thank u", etc.
- There is no tool which name is Cadence.
- Always describe correct tool's name and vendor's name which you use as tool or simulator.
- There are many simulators which have analyses called as PSS, PAC and Pnoise.
- Describe in detail and correctly with using correct terminologies.
- Warnigns are different from Errors.
- Don't use Direct Plot of Cadence ADE blindly without knowing definition.
- Don't mix up Simulation with Post Processing. They are completely different phase.

•

6. ## Re: calculation and plot of phase noise for phase frequency detector in cadence

Originally Posted by pancho_hideboo
If you use Cdence APS, I recommend you to use Shooting-PSS/FullSpectrum-Pnoise.
See http://www.designers-guide.org/Forum...1438976388/2#2

It's very easy.

See page-36 in the following.
http://een.iust.ac.ir/profs/Abrisham...20HspiceRF.pdf

Assume PFD have two inputs, ref_clk and fb_clk.

Sweep phase difference between ref_clk and fb_clk in PSS.
And then plot real part of zero order harmonics of current flowing to load voltage source which is biased at typical vcontrol voltage for VCO.
Next apply deriv() to Icp v.s. delta_phi.

The following is a case of Synopsys HSPICE.
However it can be same as Cadence Spectre.

The followings are general notes for you.

- Don't use unfamiliar abbreviations such as "U R right", "Do U", "thank u", etc.
- There is no tool which name is Cadence.
- Always describe correct tool's name and vendor's name which you use as tool or simulator.
- There are many simulators which have analyses called as PSS, PAC and Pnoise.
- Describe in detail and correctly with using correct terminologies.
- Warnigns are different from Errors.
- Don't use Direct Plot of Cadence ADE blindly without knowing definition.
- Don't mix up Simulation with Post Processing. They are completely different phase.