有關hspice inverter chain design

ShengKuanLa@FB

不好意思，大學修積體電路導論，目前的作業出到inverter chain 但卡在這好久，麻煩前輩們解惑了!問題是4階inverter chain，條件給了minimum size還有基本的cl 1pf等等，我用了網路建議的f=3.8試看看，第一關跑圖就失敗了。。。tr0跑出來的圖形歪七扭八整片顏色。。。下面是我的gedit inv.sp

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*****circuit****
.subckt sub1 in out vdd vss
6 C: ~8 p7 u: F- T! tMp1 out in vdd vdd P_18 w=3u l=0.18u m=1
Mn1 out in vss vss N_18 w=1u l=0.18u m=1
.ends sub1
* J; M* {% s" t+ |
4 r9 Z- ]( t; K- [# x% ~.subckt sub2 in out vdd vss
Mp2 out in vdd vdd P_18 w=11.4u l=0.18 m=2
$ ^+ K4 r/ K$ G0 lMn2 out in vss vss N_18 w=3.8u l=0.18u m=2
, L, E0 @) n7 e  n2 Y/ R( I.ends sub2

.subckt sub3 in out vdd vss
Mp3 out in vdd vdd P_18 w=43.32u l=0.18u m=3
Mn3 out in vss vss N_18 w=14.44u l=0.18u m=3
7 G4 ^$ J8 K' g; h4 ~.ends sub3
4 v9 W9 }" s7 C' ]$ {
.subckt sub4 in out vdd vss
Mp4 out in vdd vdd P_18 w=164.6u l=0.18u m=4
Mn4 out in vss vss N_18 w=54.87u l=0.18u m=4
' [' F. b" D, x' \& i.ends sub4
3 }% \% W+ l1 m1 i/ p5 z
xsub1 a b c 0 sub1
8 f4 o/ \5 D# \/ f; Xxsub2 b d e 0 sub2
" ]& W  c% t3 \+ @1 Cxsub3 d f g 0 sub3
xsub4 f h i 0 sub4
6 g3 ?. ~  ]' L2 |cl h 0 1pf


8 Y( O3 A8 M( u6 Q0 e2 Z*****source******
" q, i6 E" _  i- D* Y  N; cvdd c 0 1.8
vdd e 0 1.8
& A! }% F8 W3 `" l5 Jvdd g 0 1.8
* e$ ~+ L: _5 ^5 M5 dvdd i 0 1.8
' [2 [$ t6 ?4 P1 L6 O8 rvgnd vss 0 0
vin a 0 pulse(0 1.8 1n 0.5n 0.5n 4.5n 10n)
*vin a 0 0.9
8 _* v- l* q) P# K, K

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