How to plot Noise Modulating Function for VCOs in Cadence Virtuoso?

Please contact Cadence Support https://support.cadence.com and file a Case.  You are welcome to put me on the Case cc list.   I'm investigating this.

best regards,

Tawna

I'm sorry but what do you mean by "file a case."

As in, take legal action?

I'm sorry but what do you mean by "file a case."

As in, take legal action?

Are you a university student?  If so, talk to your professor (or professor who is the Cadence contact person) and ask them to file a Case on https://support.cadence.com .   A "Case" is a "support ticket" so we can investigate and file a CCR (Cadence Change Request) if necessary to update our software.  If you are a Cadence customer on Maintenance, then you can create a login on the https://support.cadence.com website, login, and create a "Case".   A Customer Support AE will contact you.  

I am familiar with the term NMF.  I'm talking to R&D about this. 

best regards,

Tawna

Dear Srayan,

Srayan said:

NMF multiplied by ISF gives the effective ISF of the oscillating node.

It is present in literature. You can find it here: "A noise shifting differential colpitts vco", Roberto Aparicio & Ali Hajimiri.

Thank you for this reference! I did review it and now understand what you are interested in. In the case the paper points to it simply represents the portion of the ISF due to the 1/f noise of the bias current. What I might suggest is that you create a probe for the bias current of your VCO to use an output. Then, follow the procedure I outline in the Forum post at URL:

community.cadence.com/.../isf-function-extraction-in-cadence-virtuoso

This will provide a ppv file from which you may plot the portion due to the saved current probe. There is some added information concerning ISF and ppv in the more recent Forum post at:

https://community.cadence.com/cadence_technology_forums/f/rf-design/47454/isf-simulation-using-transient-analysis-by-injecting-impulse

Srayan said:

I'm sorry but what do you mean by "file a case."

"File a case" is the process by which you request Cadence to investigate an issue with your use of the Cadence tools. More information may be found at URL:

https://www.cadence.com/en_US/home/support/customer-support-contacts.html

Shawn

Thank you.

I'll get back to you if necessary, I hope that's alright.

Hello,

I plotted the ISF for my oscillating nodes. I would like to superimpose the transient waveform and the ISF plot of the oscillating node for a better understanding. 

How do I do that?

Furthermore, the ISF is plotted for some pico seconds (50 ps approx) but the oscillations in my VCO don't start till 4 ns. I am guessing this might be an issue while superimposing the 2 plots. How do I resolve that?

Finally, for plotting NMF you suggested "create a probe for the bias current of your VCO to use an output" and then plot the PPV data for this probe. What I understood is that I plot the PPV data for the node connected to the bias current (like the source node for a cross coupled NMOS LC VCO) to get the NMF of the VCO.

Is my understanding correct?

Regards,

Srayan Sankar Chatterjee