spice

Vdd  8  0  dc 5.
V1   1  0  pulse iv=0 pv=5 rise=10n width=10n fall=10n period=50n
U2   2  1  mos inv
.model  mos logic ( delay= 2n  rise= 1n  fall= 1n  rs= 100.  rw= 1.G 
+ thh= 0.75  thl= 0.25  mr= 5.  mf= 5.  over=10k vmax= 5.  vmin= 0. )


.print tran v(nodes) logic(nodes) control(0)
.tran 100n
.end