Stats

  • Locked Locked
  • Replies 1
  • Subscribers 63
  • Views 2197
  • Members are here 0
This discussion has been locked.
You can no longer post new replies to this discussion. If you have a question you can start a new discussion

Minimum beat frequency setting for PSS analysis to have smaller step size sweep in PAC,PXF

RFQuery

 Hi,

 I know the beat frequency setting for PSS should be the minimum frequency of the circuit signal frequency. 

But I want to sweep the PAC analysis with a step size less than my circuit frequency.  So I chnage my PSS beat frequency to the minimum step size of the PAC. But this resulted a huge difference in the transient analysis and PSS-transient analysis (tstab plot).

So is there any lower limit of beat frequency setting in PSS.

 

Parents
  • Andrew Beckett

    There's no lower limit, but doing this will mean your simulation is very long as you will have many cycles of the high frequency content - and this it will take a long time and a lot of memory. I can't see any particular reason why there should be a huge different in the tstab and transient, since essentially the tstab is a transient.

    Anyway, regardless of this, it's unnecessary to set the PSS fundamental lower just because you're using a lower frequency in the PAC. I don't know why you're doing that. If it was the other way around - needing a very high frequency in the PAC compared with the PSS fundamental (e.g. above 40 times the PSS fundamental), you might need to either set maxacfreq or increase maxharms to ensure that there are sufficient points in the time domain solution at the frequency of interest, but you don't need to do anything like this for low frequencies.

    Andrew.

Reply
  • Andrew Beckett

    There's no lower limit, but doing this will mean your simulation is very long as you will have many cycles of the high frequency content - and this it will take a long time and a lot of memory. I can't see any particular reason why there should be a huge different in the tstab and transient, since essentially the tstab is a transient.

    Anyway, regardless of this, it's unnecessary to set the PSS fundamental lower just because you're using a lower frequency in the PAC. I don't know why you're doing that. If it was the other way around - needing a very high frequency in the PAC compared with the PSS fundamental (e.g. above 40 times the PSS fundamental), you might need to either set maxacfreq or increase maxharms to ensure that there are sufficient points in the time domain solution at the frequency of interest, but you don't need to do anything like this for low frequencies.

    Andrew.

Children
No Data

Community Guidelines

The Cadence Design Communities support Cadence users and technologists interacting to exchange ideas, news, technical information, and best practices to solve problems and get the most from Cadence technology. The community is open to everyone, and to provide the most value, we require participants to follow our Community Guidelines that facilitate a quality exchange of ideas and information. By accessing, contributing, using or downloading any materials from the site, you agree to be bound by the full Community Guidelines.