The Designer's Guide Community
Forum
Welcome, Guest. Please Login or Register. Please follow the Forum guidelines.
Apr 16th, 2024, 1:09pm
Pages: 1 2 
Send Topic Print
simulating phase noise of differential LC-VCO in spectre (Read 6483 times)
oermens
Community Member
***
Offline



Posts: 86

Re: simulating phase noise of differential LC-VCO in spectre
Reply #15 - Dec 09th, 2008, 5:10pm
 
this is our version: MMSIM.61.ISR200706210503

i'm not sure but setting the CDS_SPECTRERF_FBENABLE variable was the only way to get the option for shooting or flexible balance.
Back to top
 
 
View Profile   IP Logged
pancho_hideboo
Senior Fellow
******
Offline



Posts: 1424
Real Homeless
Re: simulating phase noise of differential LC-VCO in spectre
Reply #16 - Dec 9th, 2008, 5:22pm
 
oermens wrote on Dec 9th, 2008, 5:10pm:
this is our version: MMSIM.61.ISR200706210503

Show me version correctly by executing the followings.

% spectre -V
% icms -V

% spectre -W
% icms -W

Your version of DFII might be old.
Back to top
 
 
View Profile WWW Top+Secret Top+Secret   IP Logged
oermens
Community Member
***
Offline



Posts: 86

Re: simulating phase noise of differential LC-VCO in spectre
Reply #17 - Dec 9th, 2008, 5:52pm
 
$ spectre -V
@(#)$CDS: spectre  version 6.1.1 06/17/2007 07:20
$ icfb -V
@(#)$CDS: icfb.exe version 5.1.0 06/20/2007 02:40
$ spectre -W
sub-version  6.1.1.424
$ icfb -W
sub-version 5.10.41_USR5.90.69
Back to top
 
 
View Profile   IP Logged
pancho_hideboo
Senior Fellow
******
Offline



Posts: 1424
Real Homeless
Re: simulating phase noise of differential LC-VCO in spectre
Reply #18 - Dec 9th, 2008, 6:09pm
 
oermens wrote on Dec 9th, 2008, 5:52pm:
$ @(#)$CDS: spectre  version 6.1.1 06/17/2007 07:20
@(#)$CDS: icfb.exe version 5.1.0 06/20/2007 02:40

It seems that your versions are OK for both Spectre and DFII.

Execute "spectre -h pss".
Can you confirm "Harmonic Balance parameters" such as followings ?
  harmonicbalance=no
  flexbalance=no

Show me netlist regarding pss statement.
Back to top
 
 
View Profile WWW Top+Secret Top+Secret   IP Logged
oermens
Community Member
***
Offline



Posts: 86

Re: simulating phase noise of differential LC-VCO in spectre
Reply #19 - Dec 9th, 2008, 6:18pm
 
Harmonic Balance parameters
50      harmonicbalance=no
                         Use Harmonic Balance engine instead of time-
                         domain shooting.  Possible values are no or
                         yes.
51      flexbalance=no    Same parameter as `harmonicbalance'.
                         Possible values are no or yes.
52      pinnode           Node to pin during autonomous HB
                         simulation.
53      oversamplefactor=1
                         Oversample device evaluations.
54      oversample=[...]  Array of oversample factors for each tone.
                         It overrrides oversamplefactor.
55      oscmethod         Osc Newton method for autonomous HB:
                         onetier (default) or twotier.


im not at my desk, i'm executing over ssh and i'm not familiar with executing simulation via command line so i cant get netlist, but anyways all there was related to flexbalace was the message i posted previously. i will get the netlist tomorrow morning

---

this is what comes in spectre.out related to flexbalance:


Warning from spectre during circuit read-in.
   pss: `flexbalance' is not a valid parameter for an instance of `pss'.
       Ignored.
Back to top
 
« Last Edit: Dec 10th, 2008, 8:54am by oermens »  
View Profile   IP Logged
oermens
Community Member
***
Offline



Posts: 86

Re: simulating phase noise of differential LC-VCO in spectre
Reply #20 - Dec 12th, 2008, 7:12pm
 
sorry for delay. here is the relevant part of netlist

simulatorOptions options reltol=1e-3 vabstol=1e-6 iabstol=1e-12 temp=25 \
   tnom=25 scalem=1.0 scale=1.0 gmin=1e-12 rforce=1 maxnotes=5 maxwarns=5 \
   digits=5 cols=80 pivrel=1e-3 ckptclock=1800 \
   sensfile="../psf/sens.output" checklimitdest=psf
sweeppss  sweep  dev=V7  param=dc  start=-0.55  stop=0.95
+         lin=10  {
 pss  (  net018  net036  )  pss  flexbalance=yes  fund=2G  harms=7
+      errpreset=moderate  tstab=150n  saveinit=yes  cmin=1f
+      annotate=status

 pnoise  (  net018  net036  )  pnoise  sweeptype=relative
+         relharmnum=1  start=0.01M  stop=100M  dec=20  maxsideband=7
+         annotate=status
}
Back to top
 
 
View Profile   IP Logged
pancho_hideboo
Senior Fellow
******
Offline



Posts: 1424
Real Homeless
Re: simulating phase noise of differential LC-VCO in spectre
Reply #21 - Dec 12th, 2008, 10:27pm
 
oermens wrote on Dec 12th, 2008, 7:12pm:
 pss  (  net018  net036  )  pss  flexbalance=yes  fund=2G  harms=7
+      errpreset=moderate  tstab=150n  saveinit=yes  cmin=1f
+      annotate=status

There is no problem in your PSS statement.

I suspect your spectre version.
Even though a result of "spectre -V" is version 6.1, spectre version could be still 5.1 in ADE.

Show me version of spectre in logfile of spectre simulation.
Back to top
 
 
View Profile WWW Top+Secret Top+Secret   IP Logged
oermens
Community Member
***
Offline



Posts: 86

Re: simulating phase noise of differential LC-VCO in spectre
Reply #22 - Dec 13th, 2008, 7:22am
 
input.scllog:spectre (ver. 5.10.41_USR5.053107 -- 31 May 2007).

from spectre.out:

Environment variable:
   SPECTRE_DEFAULTS=-I/***/IC/tools/dfII/local/lib/cmosp13/../../Spectre/models -f psfbin
Command line:
   /***/IC/tools.sun4v/spectre/bin/32bit/spectre -env  \
       artist5.1.0 +escchars +log ../psf/spectre.out +inter=mpsc  \
       +mpssession=spectre0_2856_18 -format sst2 -raw ../psf  \
       -I/***/models  \
       +lqtimeout 900 input.scs

from recent CDSlogs logfile

\o Program:             @(#)$CDS: icfb.exe version 5.1.0 06/20/2007 02:40 (cicsun11) $
\o Hierarchy:           /*/cadence.2007a/IC.5141.USR5/tools.sun4v/dfII/
\o Sub version:         sub-version 5.10.41_USR5.90.69 (32-bit addresses)
\o Host name (type):    * (sun4u)
\o Operating system:    SunOS 5.10 Generic_137111-08
\o X display name:      :0.0
\o X server:            Sun Microsystems, Inc.
\o Depth of Visual (Root):      8 (24)
\o Number of Planes Used:       8
\o X version:           11.0 (vendor release 6620)


i was reading something online and found that there are 2 spectre's - 1 as part of IC and one part of MMSIM. how do I know which one I'm using? i don't see any references to mmsim in relation to spectre in any log file, so i'm using IC?
Back to top
 
 
View Profile   IP Logged
pancho_hideboo
Senior Fellow
******
Offline



Posts: 1424
Real Homeless
Re: simulating phase noise of differential LC-VCO in spectre
Reply #23 - Dec 13th, 2008, 7:41am
 
oermens wrote on Dec 13th, 2008, 7:22am:
input.scllog:spectre (ver. 5.10.41_USR5.053107 -- 31 May 2007).
from spectre.out:

As I suspect, you are using Spectre 5.1 in ADE.

If you want to use MMSIM6.1, set MMSIM6.1 prior to DFII5.1 in command search path.
Back to top
 
 
View Profile WWW Top+Secret Top+Secret   IP Logged
oermens
Community Member
***
Offline



Posts: 86

Re: simulating phase noise of differential LC-VCO in spectre
Reply #24 - Dec 13th, 2008, 11:35am
 
What should I change? In our startup script, MMSIM comes before IC.

Code:
#MMSIM
PATH=/bin:/usr/bin:/usr/local/bin:/opt/pkg/bin
PATH=$PATH:$CDS_TOP_DIR/MMSIM/tools/bin

#IC
PATH=$PATH:$CDS_HOME/tools/bin
PATH=$PATH:$CDS_HOME/tools/dfII/bin
PATH=$PATH:$CDS_HOME/tools/dfII/local/bin 



($CDS_HOME = $CDS_TOP_DIR/IC)

when I type 'which spectre' it finds it in $CDS_TOP_DIR/MMSIM/tools/bin/, but when spectre is invoked in ADE, it chooses $CDS_HOME/tools.sun4v/spectre/bin/32bit/
Back to top
 
 
View Profile   IP Logged
pancho_hideboo
Senior Fellow
******
Offline



Posts: 1424
Real Homeless
Re: simulating phase noise of differential LC-VCO in spectre
Reply #25 - Dec 13th, 2008, 8:15pm
 
oermens wrote on Dec 13th, 2008, 11:35am:
when I type 'which spectre' it finds it in $CDS_TOP_DIR/MMSIM/tools/bin/, but when spectre is invoked in ADE, it chooses $CDS_HOME/tools.sun4v/spectre/bin/32bit/

Maybe your icms or icfb is wrapper which ignore your path setting. Confirm administrator whether he make any script for icms or icfb.

Show me result of getShellEnvVar("PATH") in CIW.
Back to top
 
 
View Profile WWW Top+Secret Top+Secret   IP Logged
oermens
Community Member
***
Offline



Posts: 86

Re: simulating phase noise of differential LC-VCO in spectre
Reply #26 - Dec 13th, 2008, 9:16pm
 
i'll talk to my admin on monday. should i suggest switching from the IC stream to MMSIM stream? if so, how will that affect the functionality of other tools? besides my lab, we have an undergrad course next semester which will be using cadence and i don't want to mess around with the tools unless we know excatly what to change.

in the mean time, i've got flexbalance working by using ocean to execute all the commands. the results are close (within less than 1dB) between shooting and flexbalance at the points of interest. i am running over ssh and can't export display (disabled by admin), so i'm using ocean -nograph. i've started learning a bit of scripting, now i can run PSS+PNOISE and export to .ps to see results. is it possible to do the following?

run pss+pnoise using shooting
plot pnoise to new window, hold the result
run pss+pnoise using flexbalance
append pnoise to previous window
print result to ps

(i guess i should start a new thread related to ocean now)
Back to top
 
 
View Profile   IP Logged
pancho_hideboo
Senior Fellow
******
Offline



Posts: 1424
Real Homeless
Re: simulating phase noise of differential LC-VCO in spectre
Reply #27 - Dec 14th, 2008, 1:28am
 
oermens wrote on Dec 13th, 2008, 9:16pm:
should i suggest switching from the IC stream to MMSIM stream? if so, how will that affect the functionality of other tools?

I don't know your environment. So I can't recommend it.
But I don't use old Spectre such as version 5.1.
Phase noise decomopsition to AM/PM ability might be unavailable in Spectre 5.1.

oermens wrote on Dec 13th, 2008, 9:16pm:
is it possible to do the following?
 run pss+pnoise using shooting
 plot pnoise to new window, hold the result
 run pss+pnoise using flexbalance
 append pnoise to previous window
 print result to ps

No, you can't do the above tasks in "-nograph" environment.
You have to write data in text file such as CSV style then use some graph drawing tool such as microsoft excel.

If you lauch ocean without "-nograph", you can do the above tasks.
Here you can also execute other vendor tools such as ADSsim in RFDE or Agilent GoldenGate which can produce PSF data.

See the followings.
http://www.designers-guide.org/Forum/YaBB.pl?num=1208334972
http://www.designers-guide.org/Forum/YaBB.pl?num=1205223090

oermens wrote on Dec 13th, 2008, 9:16pm:
(i guess i should start a new thread related to ocean now)

From first, your post is not "Phase Noise and Jitter Measurements".
Back to top
 
 
View Profile WWW Top+Secret Top+Secret   IP Logged
monicaf
New Member
*
Offline



Posts: 1

Re: simulating phase noise of differential LC-VCO in spectre
Reply #28 - Jul 10th, 2009, 3:15am
 
Hi,
I have the same problem as oermens.
I'm running Cadence ICv5.1.41USR5 in centOS.
I need to simulate with spectre from MMSIM, but ADE always chooses spectre from cds/IC.
I have configured the environment variables as described in this forum (mmsim path appears before IC path in bashrc) but still, spectre runs from IC. Do you know what can I be possibly doing wrong?
Thank you.
Monica
Back to top
 
 
View Profile   IP Logged
Andrew Beckett
Senior Fellow
******
Offline

Life, don't talk to
me about Life...

Posts: 1742
Bracknell, UK
Re: simulating phase noise of differential LC-VCO in spectre
Reply #29 - Jul 10th, 2009, 5:52am
 
Best not to post an update in a thread that was over 6 months old. I doubt your problem is anything related to the issue here.

My guess is that you have:

<MMSIMinstDir>/tools/bin

in your $path (or $PATH depending on the shell), but the "tools" link is missing in the MMSIM installation.

MMSIM releases (at least recent ones) do not automatically add the "tools" link (unfortunately) and as a result this becomes a rather regularly occurring problem.

So you need to go to your MMSIM installation and do:

ln -s tools.lnx86 tools

(if it's not there already).

You can check if it's really in your path by typing "spectre -W" and seeing if it shows the right version number.

Regards,

Andrew.
Back to top
 
 
View Profile WWW   IP Logged
Pages: 1 2 
Send Topic Print
Copyright 2002-2024 Designer’s Guide Consulting, Inc. Designer’s Guide® is a registered trademark of Designer’s Guide Consulting, Inc. All rights reserved. Send comments or questions to editor@designers-guide.org. Consider submitting a paper or model.