* Effecting a Monte Carlo calculation in ngspice
V1 N001 0 AC 1 DC 0
R1 N002 N001 141
*
C1 OUT 0 1e-09
L1 OUT 0 10e-06
C2 N002 0 1e-09
L2 N002 0 10e-06
L3 N003 N002 40e-06
C3 OUT N003 250e-12
*
R2 0 OUT 141
.control
let mc_runs = 5
let run = 0
set curplot=new $ create a new plot
set scratch=$curplot $ store its name to 'scratch'
setplot $scratch $ make 'scratch' the active plot
let bwh=unitvec(mc_runs) $ create a vector in plot 'scratch' to store bandwidth data
* define distributions for random numbers:
* unif: uniform distribution, deviation relativ to nominal value
* aunif: uniform distribution, deviation absolut
* gauss: Gaussian distribution, deviation relativ to nominal value
* agauss: Gaussian distribution, deviation absolut
* limit: if unif. distributed value >=0 then add +avar to nom, else -avar
define unif(nom, rvar) (nom + (nom*rvar) * sunif(0))
define aunif(nom, avar) (nom + avar * sunif(0))
define gauss(nom, rvar, sig) (nom + (nom*rvar)/sig * sgauss(0))
define agauss(nom, avar, sig) (nom + avar/sig * sgauss(0))
* define limit(nom, avar) (nom + ((sgauss(0) ge 0) ? avar : -avar))
define limit(nom, avar) (nom + ((sgauss(0) >= 0) ? avar : -avar))
*
*
dowhile run < mc_runs $ loop starts here
*
* alter c1 = unif(1e-09, 0.1)
* alter c1 = aunif(1e-09, 100e-12)
* alter c1 = gauss(1e-09, 0.1, 3)
* alter c1 = agauss(1e-09, 100e-12, 3)
*
alter c1 = unif(1e-09, 0.1)
alter l1 = unif(10e-06, 0.1)
alter c2 = unif(1e-09, 0.1)
alter l2 = unif(10e-06, 0.1)
alter l3 = unif(40e-06, 0.1)
alter c3 = limit(250e-12, 25e-12)
*
ac oct 100 250K 10Meg
*
* measure bandwidth at -10 dB
meas ac bw trig vdb(out) val=-10 rise=1 targ vdb(out) val=-10 fall=1
*
set run ="$&run" $ create a variable from the vector
set dt = $curplot $ store the current plot to dt
setplot $scratch $ make 'scratch' the active plot
let vout{$run}={$dt}.v(out) $ store the output vector to plot 'scratch'
let bwh[run]={$dt}.bw $ store bw to vector bwh in plot 'scratch'
setplot $dt $ go back to the previous plot
let run = run + 1
end $ loop ends here
*
plot db({$scratch}.allv)
echo
print {$scratch}.bwh
.endc
.end*Digital inverter
.PARAM V_SUPPLY = '#V_SUPPLY#'
.PARAM INP_FREQ = '#INP_FREQ#'
.PARAM INP_PERIOD = '1/INP_FREQ'
.PARAM NO_PERIODS = '4'
.PARAM TMEAS_START = '(NO_PERIODS-1)*INP_PERIOD'
.PARAM TMEAS_STOP = '(NO_PERIODS)*INP_PERIOD'
.PARAM TMEAS_1 = 'TMEAS_STOP -3*INP_PERIOD/4'
.PARAM TMEAS_2 = 'TMEAS_STOP -1*INP_PERIOD/4'
*** *** SUPPLY VOLTAGES *** ***
VDD VDD 0 {V_SUPPLY}
VSS VSS 0 0
*** *** INPUT SIGNAL *** ***
VSIG IN VSS PULSE {V_SUPPLY} 0 'INP_PERIOD/2' 'INP_PERIOD/1000'
+ 'INP_PERIOD/1000' 'INP_PERIOD/2' 'INP_PERIOD'
*** *** ROUT TEST CIRCUIT *** ***
MP OUT IN VDD VDD P1 W='#WP#' L=#LMIN#
MN OUT IN VSS VSS N1 W='#WP#/2' L=#LMIN#
CL OUT VSS 3p
*** *** ANALYSIS *** ***
.TRAN 'INP_PERIOD/1000' 'NO_PERIODS*INP_PERIOD'
*
*.PROBE TRAN V(IN)
*.PROBE TRAN V(OUT)
.OPTION POST PROBE ACCURATE
.include modelcard.nmos
.include modelcard.pmos
.END*CMOS inverter
.PARAM V_SUPPLY = '#V_SUPPLY#'
.PARAM V_OUT = '#V_OUT#'
.PARAM INP_FREQ = '#INP_FREQ#'
.PARAM INP_PERIOD = '1/INP_FREQ'
.PARAM AC_POINTS = 10000
.PARAM AC_START = 10
.PARAM AC_STOP = 1000000
*** *** SUPPLY VOLTAGES *** ***
VDD VDD 0 {V_SUPPLY}
VSS VSS 0 0
*** *** INPUT SIGNAL *** ***
VSIG IN VSS VSS
*** *** CIRCUIT UNDER TEST *** ***
MP OUT IN VDD VDD P1 W='#WP#' L=#LMIN#
MN OUT IN VSS VSS N1 W='#WP#/2' L=#LMIN#
CL OUT VSS 3p
*** *** ROUT TEST SIGNAL *** ***
VOUT VOUT '#V_OUT#' VSS
IOUT OUT VOUT 1A
*** *** ANALYSIS *** ***
.AC dec 'AC_POINTS' 'AC_START' 'AC_STOP'
*
*.PROBE TRAN V(IN)
*.PROBE TRAN V(OUT)
.OPTION POST PROBE ACCURATE
.include modelcard.nmos
.include modelcard.pmos
.END#Optimization Flow#
Alter:yes $do we want to do corner analysis?
MonteCarlo:no $do we want to do MonteCarlo analysis?
AlterMC cost:3.00 $point at which we want to start ALTER and/or MONTECARLO
ExecuteRF:no $execute or not the RF module to add RF parasitics?
SomethingElse: $
#
#DE#
choice of method:3
maximum no. of iterations:50
Output refresh cycle:2
No. of parents NP:10
Constant F:0.5
Crossover factor CR:1
Seed for pseudo random number generator:3
Minimum Cost Variance:1e-6
Cost objectives:10
Cost constraints:10000
#
# ALTER #
.control
alter vdd=[2.0 2.1 2.2]
run
.endc
*.protect
*.inc [../models/cmos035_slow.mod ../models/cmos035_typ.mod ../models/cmos035_fast.mod]
*.unprotect
*.temp [-40 +25 +85]
*.param
*+ V_SUPPLY=[2.0 2.1 2.2]
*.protect $ As much as 6 variables can be swept at the same time.
*.lib hl49ciat57k5r200.mod [mos_wcs mos_nom mos_bcs] $ Format is [a] or [a b] or ... [a b c d e f] =>1 space
*.unprotect $ and not :[ a], [a ], [ a ] => space is not really necessary
*.temp [-40 +25 +85] $ and not :[a b] => only 1 ' ' between 'a' and 'b'
*.param $ Add '*' to skip a line
*+ vddd=[2.25 2.50 3.30] $
*+ kc=[0.95 1.05]:LIN:10 $ LIN not yet implemented
*+ kr=[0.87 1.13]:LOG:10 $ LOG not yet implemented
*+ Ierror=[0.7 1.3]
*+ k00=[0 1]
*+ k01=[0 1]
*+ k02=[0 1]
*+ k03=[0 1]
*+ k04=[0 1]
*+ k05=[0 1]
*+ k06=[0 1]
*+ k07=[0 1]
*+ k08=[0 1]
*+ k09=[0 1]
#
#Monte Carlo#
NMOS_AVT:12.4mV $ This values will be divided by sqrt(2) by the program
NMOS_ABETA:7.3% $ 'm' parameter is taken into account
PMOS_AVT:10.9mV $
PMOS_ABETA:3.7% $
SMALL_LENGTH:0.0u $ Small transistors if l<= SMALL_LENGTH
SMALL_NMOS_AVT:20mV $ Small transistors parameters
SMALL_NMOS_ABETA:10% $
SMALL_PMOS_AVT:10mV $
SMALL_PMOS_ABETA:5% $
R_DELTA:0.333% $ Resistors matching at 1 sigma between two resistors
L_DELTA:0.333% $ Inductors matching at 1 sigma between two inductors
C_DELTA:0.333% $ Capacitors matching at 1 sigma between two capacitors
#
# Parameters #
Supply voltage:#V_SUPPLY#:2.0:0:0:LIN_DOUBLE:---
Temperature:#TEMP#:25:0:0:LIN_DOUBLE:---
Minimal gate length:#LMIN#:0.35u:0:0:LIN_DOUBLE:---
Input frequency:#INP_FREQ#:850E6:0:0:LIN_DOUBLE:---
PMOS width:#WP#:10000u:1m:10m:LIN_DOUBLE:OPT
Output voltage:#V_OUT#:1:1:5:LIN_DOUBLE:OPT
#
# Measurements #
#P_SUPPLY:---:MIN:0
#VHIGH:OUT:GE:1.95
#VLOW:OUT:LE:0.05
ROUT:OUT:GE:1000
#
# Post Processing #
#
#this is the last line*CMOS inverter
.PARAM V_SUPPLY = '#V_SUPPLY#'
.PARAM V_OUT = '#V_OUT#'
.PARAM INP_FREQ = '#INP_FREQ#'
.PARAM INP_PERIOD = '1/INP_FREQ'
.PARAM NO_PERIODS = '4'
.PARAM TMEAS_START = '(NO_PERIODS-1)*INP_PERIOD'
.PARAM TMEAS_STOP = '(NO_PERIODS)*INP_PERIOD'
.PARAM AC_POINTS = 10000
.PARAM AC_START = 10
.PARAM AC_STOP = 1000000
*** *** SUPPLY VOLTAGES *** ***
VDD VDD 0 {V_SUPPLY}
VSS VSS 0 0
*** *** INPUT SIGNAL *** ***
VSIG IN VSS VSS
*** *** CIRCUIT UNDER TEST *** ***
MP OUT IN VDD VDD P1 W='#WP#' L=#LMIN#
MN OUT IN VSS VSS N1 W='#WP#/2' L=#LMIN#
Lf OUT IN 0.01
** The input can be either biased with a DC source, or a DC feedback circuit. Using a DC feedback circuit (RC, inductor, whatsoever) makes only sense if there's no DC voltage source, see https://www.edaboard.com/showthread.php?377214-Noise-in-CMOS-Inverter&p=1617292&viewfull=1#post1617292
*** *** ROUT TEST SIGNAL WITH FIXED 1A CURRENT AND VARIABLE TEST VOLTAGE (VOUT) *** ***
VOUT OUT '#V_OUT#' VSS
IOUT OUT VOUT 1
*** *** ANALYSIS *** ***
.AC dec 'AC_POINTS' 'AC_START' 'AC_STOP'
*
*.PROBE TRAN V(IN)
*.PROBE TRAN V(OUT)
.OPTION POST PROBE ACCURATE
.include modelcard.nmos
.include modelcard.pmos
.END# Info #
Name:ROUT
Symbol:Z_ROUT
Unit:Ω
Analysis type:AC
Definition:Output Impedance
Note:
#
# Commands #
.measure ac #SYMBOL# par('VOUT/1')
#