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 inverter3.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 .param skew_meas = 'vp/2' * 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 .meas tran inv_delay trig v(in) val='vp/2' fall=1 targ v(out) val='vp/2' rise=1 .meas tran inv_delay2 trig v(in) val='vp/2' td=1n fall=1 targ v(out) val='vp/2' rise=1 .meas tran test_data1 trig AT = 1n targ v(out) val='vp/2' rise=3 .meas tran out_slew trig v(out) val='0.2*vp' rise=2 targ v(out) val='0.8*vp' rise=2 .meas tran delay_chk param='(inv_delay < 100ps) ? 1 : 0' .meas tran skew when v(out)=0.6 .meas tran skew2 when v(out)=skew_meas .meas tran skew3 when v(out)=skew_meas fall=2 .meas tran skew4 when v(out)=skew_meas fall=LAST .meas tran skew5 FIND v(out) AT=2n .meas tran v0_min min i(v0) from='dfall' to='dfall+period' .meas tran i_v0_min min_at i(v0) from='dfall' to='dfall+period' .meas tran v0_avg avg i(v0) from='dfall' to='dfall+period' .meas tran v0_integ integ i(v0) from='dfall' to='dfall+period' .meas tran v0_rms rms i(v0) from='dfall' to='dfall+period' .control run rusage all plot v(in) v(out) .endc .end
