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Diffstat (limited to 'Windows/spice/examples/Monte_Carlo/MC_ring_ts.sp')
| -rw-r--r-- | Windows/spice/examples/Monte_Carlo/MC_ring_ts.sp | 180 |
1 files changed, 180 insertions, 0 deletions
diff --git a/Windows/spice/examples/Monte_Carlo/MC_ring_ts.sp b/Windows/spice/examples/Monte_Carlo/MC_ring_ts.sp new file mode 100644 index 00000000..ee88c329 --- /dev/null +++ b/Windows/spice/examples/Monte_Carlo/MC_ring_ts.sp @@ -0,0 +1,180 @@ +*ng_script +* Example script for Monte Carlo with commercial HSPICE-compatible libraries +* The circuit in mc_ring_circ.net is a 25-stage inverter ring oscillator. +* Add your library to mc_ring_circ.net and choose transistors accordingly. +* Add the source file and the library path. +* A simple BSIM3 inverter R.O. serves as an MC example wtihout need for a library. +.control +begin + let mc_runs = 30 $ number of runs for monte carlo + let run = 0 $ number of actual run + set curplot = new $ create a new plot + set curplottitle = "Transient outputs" + set plot_out = $curplot $ store its name to 'plot_out' + set curplot = new $ create a new plot + set curplottitle = "FFT outputs" + set plot_fft = $curplot $ store its name to 'plot_fft' + set curplot = new $ create a new plot + set curplottitle = "Oscillation frequency" + set max_fft = $curplot $ store its name to 'max_fft' + let mc_runsp = mc_runs + 1 + let maxffts = unitvec(mc_runsp) $ vector for storing max measure results + let halfffts = unitvec(mc_runsp)$ vector for storing measure results at -40dB rising + unlet mc_runsp + + set mc_runs = $&mc_runs $ create a variable from the vector + let seeds = mc_runs + 2 + setseed $&seeds + unlet seeds + + echo source the input file +* Path of your circuit file and library file here +* Will be added to the already existing sourcepath + setcs sourcepath = ( $inputdir $sourcepath ./ngspice/examples/Monte_Carlo ) +* source with file name of your circuit file + source mc_ring_circ.net + + save buf $ we just need buf, save memory by more than 10x + +* Output path (directory has already to be there) +* set outputpath = 'D:\Spice_general\ngspice\examples\Monte_Carlo\out' +* If your current directory is the 'ngspice' directory +* set outputpath = './examples/Monte_Carlo/out' $ LINUX alternative +* run the simulation loop + +* We have to figure out what to do if a single simulation will not converge. +* There is now the variable sim_status, that is 0 if simulation ended regularly, +* and 1 if the simulation has been aborted with error message '...simulation(s) aborted'. +* Then we skip the rest of the run and continue with a new run. + + dowhile run <= mc_runs + + set run = $&run $ create a variable from the vector + + * run=0 simulates with nominal parameters + if run > 0 + echo + echo * * * * * * + echo Source the circuit again internally for run no. $run + echo * * * * * * + setseed $run + mc_source $ re-source the input file + else + echo run no. $run + end + echo simulation run no. $run of $mc_runs + tran 100p 1000n 0 + echo Simulation status $sim_status + let simstat = $sim_status + if simstat = 1 + if run = mc_runs + echo go to end + else + echo go to next run + end + destroy $curplot + goto next + end + +* select stop and step so that number of data points after linearization is not too +* close to 8192, which would yield varying number of line length and thus scale for fft. +* + set dt0 = $curplot + * save the linearized data for having equal time scales for all runs + linearize buf $ linearize only buf, no other vectors needed + set dt1 = $curplot $ store the current plot to dt (tran i+1) + setplot $plot_out $ make 'plt_out' the active plot + * firstly save the time scale once to become the default scale + if run=0 + let time={$dt1}.time + end + let vout{$run}={$dt1}.buf $ store the output vector to plot 'plot_out' + setplot $dt1 $ go back to the previous plot (tran i+1) + fft buf $ run fft on vector buf + let buf2=db(mag(buf)) + * find the frequency where buf has its maximum of the fft signal + meas sp fft_max MAX_AT buf2 from=0.05G to=0.7G + * find the frequency where buf is -40dB at rising fft signal + meas sp fft_40 WHEN buf2=-40 RISE=1 from=0.05G to=0.7G + * store the fft vector + set dt2 = $curplot $ store the current plot to dt (spec i) + setplot $plot_fft $ make 'plot_fft' the active plot + if run=0 + let frequency={$dt2}.frequency + end + let fft{$run}={$dt2}.buf $ store the output vector to plot 'plot_fft' + settype decibel fft{$run} + * store the measured value + setplot $max_fft $ make 'max_fft' the active plot + let maxffts[{$run}]={$dt2}.fft_max + let halfffts[{$run}]={$dt2}.fft_40 + destroy $dt0 $dt1 $dt2 $ save memory, we don't need this plot (spec) any more + + label next + remcirc + let run = run + 1 + end +***** plotting ********************************************************** +if $?batchmode + echo + echo Plotting not available in batch mode + echo Write linearized vout0 to vout{$mc_runs} to rawfile $rawfile + echo + write $rawfile {$plot_out}.allv + rusage + quit +else + if $?sharedmode or $?win_console + gnuplot xnp_pl1 {$plot_out}.vout0 $ just plot the tran output with nominal parameters + else + plot {$plot_out}.vout0 $ just plot the tran output with nominal parameters + end + setplot $plot_fft + if $?sharedmode or $?win_console + gnuplot xnp_pl2 db(mag(ally)) xlimit 0 1G ylimit -80 10 + else + plot db(mag(ally)) xlimit 0 1G ylimit -80 10 + end +* +* create a histogram from vector maxffts + setplot $max_fft $ make 'max_fft' the active plot + set startfreq=50MEG + set bin_size=1MEG + set bin_count=100 + compose osc_frequ start=$startfreq step=$bin_size lin=$bin_count $ requires variables as parameters + settype frequency osc_frequ + let bin_count=$bin_count $ create a vector from the variable + let yvec=unitvec(bin_count) $ requires vector as parameter + let startfreq=$startfreq + let bin_size=$bin_size + * put data into the correct bins + let run = 0 + dowhile run < mc_runs + set run = $&run $ create a variable from the vector + let val = maxffts[{$run}] + let part = 0 + * Check if val fits into a bin. If yes, raise bin by 1 + dowhile part < bin_count + if ((val < (startfreq + (part+1)*bin_size)) & (val >= (startfreq + part*bin_size))) + let yvec[part] = yvec[part] + 1 + break + end + let part = part + 1 + end + let run = run + 1 + end + * plot the histogram + let count = yvec - 1 $ subtract 1 because we started with unitvec containing ones + if $?sharedmode or $?win_console + gnuplot np_pl3 count vs osc_frequ combplot + else + plot count vs osc_frequ combplot + end +* calculate jitter + let diff40 = (vecmax(halfffts) - vecmin(halfffts))*1e-6 + echo + echo Max. jitter is "$&diff40" MHz +end + rusage +* quit +end |