Example that shows the new features of ngspice (Phil Barker).

examples/inverter.sp

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+Inverter example circuit
+* This netlist demonstrates the following:
+* global nodes (vdd, gnd)
+* autostop (.tran defines simulation end as 4ns but simulation stops at
+* 142.5ps when .measure statements are evaluated)
+* scale (all device units are in microns)
+* model binning (look in device.values file for which bin chosen)
+*
+*     m.x1.mn:
+*     model              = nch.2
+*
+*     m.x1.mp:
+*     model              = pch.2
+*
+* parameters
+* parameterized subckt
+* vsrc with repeat
+* .measure statements for delay and an example ternary operator
+* device listing and parameter listing
+* You can run the example circuit with this command:
+*
+* ngspice -b -o ngspice.out inverter.sp
+
+
+* global nodes
+.global vdd gnd
+
+* autostop -- stop simulation early if .measure statements done
+* scale    -- define scale factor for mosfet device parameters (l,w,area,perimeter)
+.option autostop
+.option scale = 1e-6
+
+* model binning
+.model nch.1 nmos ( version=4.4 level=54 lmin=0.1u lmax=20u wmin=0.1u wmax=10u  )
+.model nch.2 nmos ( version=4.4 level=54 lmin=0.1u lmax=20u wmin=10u  wmax=100u )
+.model pch.1 pmos ( version=4.4 level=54 lmin=0.1u lmax=20u wmin=0.1u wmax=10u  )
+.model pch.2 pmos ( version=4.4 level=54 lmin=0.1u lmax=20u wmin=10u  wmax=100u )
+
+* parameters
+.param vp     = 1.0v
+.param lmin   = 0.10
+.param wmin   = 0.12
+.param plmin  = 'lmin'
+.param nlmin  = 'lmin'
+.param wpmin  = 'wmin'
+.param wnmin  = 'wmin'
+.param drise  = 400ps
+.param dfall  = 100ps
+.param trise  = 100ps
+.param tfall  = 100ps
+.param period = 1ns
+
+* parameterized subckt
+.subckt inv in out pw='wpmin' pl='plmin' nw='wnmin' nl='nlmin'
+mp out in vdd vdd pch w='pw' l='pl'
+mn out in gnd gnd nch w='nw' l='nl'
+.ends
+
+v0 vdd gnd 'vp'
+
+* vsrc with repeat
+v1 in gnd pwl
++ 0ns                       'vp'
++ 'dfall-0.8*tfall'         'vp'
++ 'dfall-0.4*tfall'         '0.9*vp'
++ 'dfall+0.4*tfall'         '0.1*vp'
++ 'dfall+0.8*tfall'         0v
++ 'drise-0.8*trise'         0v
++ 'drise-0.4*trise'         '0.1*vp'
++ 'drise+0.4*trise'         '0.9*vp'
++ 'drise+0.8*trise'         'vp'
++ 'period+dfall-0.8*tfall'  'vp'
++ r='dfall-0.8*tfall'
+
+x1 in out inv pw=60 nw=20
+c1 out gnd 220fF
+
+.tran 1ps 4ns
+
+.measure tran inv_delay trig v(in)  val='vp/2'   fall=1 targ v(out) val='vp/2'   rise=1
+.measure tran out_slew  trig v(out) val='0.2*vp' rise=1 targ v(out) val='0.8*vp' rise=1
+.measure tran delay_chk param='(inv_delay < 100ps) ? 1 : 0'
+
+.control
+run
+show    *     > device.values
+listing param > param.values
+.endc
+
+.end
+