Stats

  • Locked Locked
  • Replies 7
  • Subscribers 125
  • Views 15453
  • 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

Why OCEAN script produce different analysis result from ADE?

datao

Hi,

I uses a scripts to analyze phase noise of a VCO at different control voltage. I found some data points are significantly different from ADE produced. Then I saved script in ADE and load the script in ocean. The phase noise calculated with ocean script is -80. But at ADE, it is -100. Anyone can tell me how to solve this problem? Thanks! The save script is attached as below. The frequency calculated are consisten, but phase noise are different from ocean script.

 

 ocnWaveformTool( 'wavescan )
fp=outfile(sprintf(nil "%s/tmp.csv" resultPATH) "a")
fprintf(fp "vc ts cf wc freq amp vcom phasenoise\n")

simulator( 'spectre )
design(     "/users/dtgong/simulation/testLCVCO/spectre/schematic/netlist/netlist")
resultsDir( "/users/dtgong/simulation/testLCVCO/spectre/schematic" )
modelFile(
    '("/home/dtgong/peregrine/PSC_Release_3.8.1/Rel_3.8.1/gc/models/psa/spectre/modellib.scs" "Nominal")
)
analysis('tran ?stop "200n"  ?errpreset "conservative"  )
analysis('pnoise ?sweeptype "relative"  ?relharmnum "1"  ?start "10K"  
        ?stop "100M"  ?maxsideband "7"  ?p "/vp0"  ?n "/vn0"  
        ?oprobe ""  ?iprobe ""  ?refsideband ""  ?ppv ""  )
analysis('pss ?fund "5.0G"  ?harms "7"  ?errpreset "conservative"  
        ?tstab "500n"  ?p "/vp0"  ?n "/vn0"  ?ppv ""  )
desVar(      "wc" 30u    )
desVar(      "wb" 10u    )
desVar(      "cf" 220p    )
desVar(      "r" 10    )
desVar(      "global_use_preLPE" 1    )
desVar(      "vc" 1.1    )
desVar(      "cl" 60f    )
envOption(
    'autoDisplay  nil
)
save( 'i "/I0/I0/R0/MINUS" "/I0/I0/L0/PLUS" "/I0/I0/L1/PLUS" )
converge( 'ic "/vn0" "0.01" )
temp( 27 )
run()
selectResult( 'tran )
;plot(getData("/vp0") getData("/vn0") getData("/I0/vb") getData("/I0/I0/R0/MINUS") getData("/I0/I0/L0/PLUS") getData("/I0/I0/L1/PLUS") getData("/I0/I0/vtail") )
freq = frequency(clip((VT("/vp0") - VT("/vn0")) 1e-08 4e-08))
;plot( freq ?expr '( "freq" ) )
Phase\ Noise\;\ dBc\/Hz\,\ Relative\ Harmonic\ \=\ 1 = phaseNoise(1 "pss_fd" ?result "pnoise")
;plot( Phase\ Noise\;\ dBc\/Hz\,\ Relative\ Harmonic\ \=\ 1 ?expr '( "Phase Noise; dBc/Hz, Relative Harmonic = 1" ) )
ph_1M = value(phaseNoise(1 "pss_fd" ?result "pnoise") 1000000.0)
;plot( ph_1M ?expr '( "ph_1M" ) )
;freq0 = (freq (VT("/vp0") - VT("/vn0")) "rising" ?xName "time" ?mode "auto" ?threshold 0.0 ?histoDisplay nil ?noOfHistoBins nil)
;plot( freq0 ?expr '( "freq0" ) )
fprintf(fp "%.3fGHz %f\n"  freq*1e-9 ph_1M)
close(fp)

 

Thanks a lot,

 

Datao

 

Parents

  • Datao,

    Make sure you're not running OCEAN and ADE at the same time. Quite likely the ADE run was using spectre's interactive mode - so you had the previous netlist still in spectre's memory.

    So to be sure, start ADE from scratch and run the simulation; copy the input.scs. Close ADE and then run your OCEAN script - and then compare the input.scs in both cases.

    Check also the spectre.out from both runs - are you using the same versions?

    Andrew.

Reply

  • Datao,

    Make sure you're not running OCEAN and ADE at the same time. Quite likely the ADE run was using spectre's interactive mode - so you had the previous netlist still in spectre's memory.

    So to be sure, start ADE from scratch and run the simulation; copy the input.scs. Close ADE and then run your OCEAN script - and then compare the input.scs in both cases.

    Check also the spectre.out from both runs - are you using the same versions?

    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.