* SPICE netlist
M1 N002 A 0 0 NMOS L=0.18u W=1.0e-4
M2 Vdd A N002 N002 PMOS L=0.18u W=1.0e-4
V1 Vdd 0 0.5
Va A 0 PULSE(0 0.5 2m 0 0 2m 4m)
M3 N005 A N009 N009 NMOS L=0.18u W=1.0e-4
M4 Vdd A N005 N005 PMOS L=0.18u W=1.0e-4
M5 Vdd B N005 N005 PMOS L=0.18u W=1.0e-4
M6 N009 B 0 0 NMOS L=0.18u W=1.0e-4
Vb B 0 PULSE(0 0.5 4m 0 0 4m 8m)
M7 Vdd A N007 N007 PMOS L=0.18u W=1.0e-4
M8 N007 B N010 N010 PMOS L=0.18u W=1.0e-4
M9 N010 A 0 0 NMOS L=0.18u W=1.0e-4
M10 N010 B 0 0 NMOS L=0.18u W=1.0e-4
M11 N001 A N004 N004 NMOS L=0.18u W=1.0e-4
M12 Vdd A N001 N001 PMOS L=0.18u W=1.0e-4
M13 Vdd B N001 N001 PMOS L=0.18u W=1.0e-4
M14 N004 B 0 0 NMOS L=0.18u W=1.0e-4
M15 N003 N001 0 0 NMOS L=0.18u W=1.0e-4
M16 Vdd N001 N003 N003 PMOS L=0.18u W=1.0e-4
M17 Vdd A N006 N006 PMOS L=0.18u W=1.0e-4
M18 N006 B N008 N008 PMOS L=0.18u W=1.0e-4
M19 N008 A 0 0 NMOS L=0.18u W=1.0e-4
M20 N008 B 0 0 NMOS L=0.18u W=1.0e-4
M21 Y N008 0 0 NMOS L=0.18u W=1.0e-4
M22 Vdd N008 Y Y PMOS L=0.18u W=1.0e-4
.tran 10m
+Level = 49
+Lint = 4.e-08 Tox = 4.e-09
+Vth0 = 0.3999 Rdsw = 250
+lmin=1.8e-7 lmax=1.8e-7 wmin=1.8e-7 wmax=1.0e-4 Tref=27.0 version =3.1
+Xj= 6.0000000E-08 Nch= 5.9500000E+17
+lln= 1.0000000 lwn= 1.0000000 wln= 0.00
+wwn= 0.00 ll= 0.00
+lw= 0.00 lwl= 0.00 wint= 0.00
+wl= 0.00 ww= 0.00 wwl= 0.00
+Mobmod= 1 binunit= 2 xl= 0
+xw= 0 binflag= 0
+Dwg= 0.00 Dwb= 0.00
+K1= 0.5613000 K2= 1.0000000E-02
+K3= 0.00 Dvt0= 8.0000000 Dvt1= 0.7500000
+Dvt2= 8.0000000E-03 Dvt0w= 0.00 Dvt1w= 0.00
+Dvt2w= 0.00 Nlx= 1.6500000E-07 W0= 0.00
+K3b= 0.00 Ngate= 5.0000000E+20
+Vsat= 1.3800000E+05 Ua= -7.0000000E-10 Ub= 3.5000000E-18
+Uc= -5.2500000E-11 Prwb= 0.00
+Prwg= 0.00 Wr= 1.0000000 U0= 3.5000000E-02
+A0= 1.1000000 Keta= 4.0000000E-02 A1= 0.00
+A2= 1.0000000 Ags= -1.0000000E-02 B0= 0.00
+B1= 0.00
+Voff= -0.12350000 NFactor= 0.9000000 Cit= 0.00
+Cdsc= 0.00 Cdscb= 0.00 Cdscd= 0.00
+Eta0= 0.2200000 Etab= 0.00 Dsub= 0.8000000
+Pclm= 5.0000000E-02 Pdiblc1= 1.2000000E-02 Pdiblc2= 7.5000000E-03
+Pdiblcb= -1.3500000E-02 Drout= 1.7999999E-02 Pscbe1= 8.6600000E+08
+Pscbe2= 1.0000000E-20 Pvag= -0.2800000 Delta= 1.0000000E-02
+Alpha0= 0.00 Beta0= 30.0000000
+kt1= -0.3700000 kt2= -4.0000000E-02 At= 5.5000000E+04
+Ute= -1.4800000 Ua1= 9.5829000E-10 Ub1= -3.3473000E-19
+Uc1= 0.00 Kt1l= 4.0000000E-09 Prt= 0.00
+Cj= 0.00365 Mj= 0.54 Pb= 0.982
+Cjsw= 7.9E-10 Mjsw= 0.31 Php= 0.841
+Cta= 0 Ctp= 0 Pta= 0
+Ptp= 0 JS=1.50E-08 JSW=2.50E-13
+N=1.0 Xti=3.0 Cgdo=2.786E-10
+Cgso=2.786E-10 Cgbo=0.0E+00 Capmod= 2
+NQSMOD= 0 Elm= 5 Xpart= 1
+Cgsl= 1.6E-10 Cgdl= 1.6E-10 Ckappa= 2.886
+Cf= 1.069e-10 Clc= 0.0000001 Cle= 0.6
+Dlc= 4E-08 Dwc= 0 Vfbcv= -1
+Level = 49
+Lint = 3.e-08 Tox = 4.2e-09
+Vth0 = -0.42 Rdsw = 450
+lmin=1.8e-7 lmax=1.8e-7 wmin=1.8e-7 wmax=1.0e-4 Tref=27.0 version =3.1
+Xj= 7.0000000E-08 Nch= 5.9200000E+17
+lln= 1.0000000 lwn= 1.0000000 wln= 0.00
+wwn= 0.00 ll= 0.00
+lw= 0.00 lwl= 0.00 wint= 0.00
+wl= 0.00 ww= 0.00 wwl= 0.00
+Mobmod= 1 binunit= 2 xl= 0.00
+xw= 0.00
+binflag= 0 Dwg= 0.00 Dwb= 0.00
+ACM= 0 ldif=0.00 hdif=0.00
+rsh= 0 rd= 0 rs= 0
+rsc= 0 rdc= 0
+K1= 0.5560000 K2= 0.00
+K3= 0.00 Dvt0= 11.2000000 Dvt1= 0.7200000
+Dvt2= -1.0000000E-02 Dvt0w= 0.00 Dvt1w= 0.00
+Dvt2w= 0.00 Nlx= 9.5000000E-08 W0= 0.00
+K3b= 0.00 Ngate= 5.0000000E+20
+Vsat= 1.0500000E+05 Ua= -1.2000000E-10 Ub= 1.0000000E-18
+Uc= -2.9999999E-11 Prwb= 0.00
+Prwg= 0.00 Wr= 1.0000000 U0= 8.0000000E-03
+A0= 2.1199999 Keta= 2.9999999E-02 A1= 0.00
+A2= 0.4000000 Ags= -0.1000000 B0= 0.00
+B1= 0.00
+Voff= -6.40000000E-02 NFactor= 1.4000000 Cit= 0.00
+Cdsc= 0.00 Cdscb= 0.00 Cdscd= 0.00
+Eta0= 8.5000000 Etab= 0.00 Dsub= 2.8000000
+Pclm= 2.0000000 Pdiblc1= 0.1200000 Pdiblc2= 8.0000000E-05
+Pdiblcb= 0.1450000 Drout= 5.0000000E-02 Pscbe1= 1.0000000E-20
+Pscbe2= 1.0000000E-20 Pvag= -6.0000000E-02 Delta= 1.0000000E-02
+Alpha0= 0.00 Beta0= 30.0000000
+kt1= -0.3700000 kt2= -4.0000000E-02 At= 5.5000000E+04
+Ute= -1.4800000 Ua1= 9.5829000E-10 Ub1= -3.3473000E-19
+Uc1= 0.00 Kt1l= 4.0000000E-09 Prt= 0.00
+Cj= 0.00138 Mj= 1.05 Pb= 1.24
+Cjsw= 1.44E-09 Mjsw= 0.43 Php= 0.841
+Cta= 0.00093 Ctp= 0 Pta= 0.00153
+Ptp= 0 JS=1.50E-08 JSW=2.50E-13
+N=1.0 Xti=3.0 Cgdo=2.786E-10
+Cgso=2.786E-10 Cgbo=0.0E+00 Capmod= 2
+NQSMOD= 0 Elm= 5 Xpart= 1
+Cgsl= 1.6E-10 Cgdl= 1.6E-10 Ckappa= 2.886
+Cf= 1.058e-10 Clc= 0.0000001 Cle= 0.6
+Dlc= 3E-08 Dwc= 0 Vfbcv= -1

* LTspice schematic (.asc)
Version 4
SHEET 1 2704 1600
WIRE -216 -752 -216 -800
WIRE 872 -752 872 -800
WIRE 1032 -752 1032 -800
WIRE 1256 -752 1256 -800
WIRE -1352 -688 -1352 -752
WIRE -1000 -688 -1000 -752
WIRE -712 -672 -712 -736
WIRE -264 -672 -328 -672
WIRE 824 -672 760 -672
WIRE 984 -672 968 -672
WIRE 1208 -672 1144 -672
WIRE -328 -592 -328 -672
WIRE -328 -592 -376 -592
WIRE -216 -592 -216 -656
WIRE -120 -592 -216 -592
WIRE 760 -592 760 -672
WIRE 760 -592 712 -592
WIRE 872 -592 872 -656
WIRE 1032 -592 1032 -656
WIRE 1032 -592 872 -592
WIRE 1144 -592 1144 -672
WIRE 1144 -592 1032 -592
WIRE -1352 -560 -1352 -608
WIRE -1000 -560 -1000 -608
WIRE -712 -544 -712 -592
WIRE -216 -528 -216 -592
WIRE 872 -528 872 -592
WIRE 1256 -528 1256 -656
WIRE -328 -448 -328 -592
WIRE -264 -448 -328 -448
WIRE 760 -448 760 -592
WIRE 824 -448 760 -448
WIRE 1144 -448 1144 -592
WIRE 1208 -448 1144 -448
WIRE -216 -384 -216 -432
WIRE 872 -384 872 -432
WIRE 1256 -384 1256 -432
WIRE 824 -304 712 -304
WIRE 872 -224 872 -288
WIRE -1112 112 -1112 64
WIRE -952 112 -952 64
WIRE 840 144 840 64
WIRE -232 160 -232 80
WIRE -1160 192 -1224 192
WIRE -1000 192 -1016 192
WIRE 792 224 744 224
WIRE -280 240 -328 240
WIRE -1224 272 -1224 192
WIRE -1224 272 -1272 272
WIRE -1112 272 -1112 208
WIRE -952 272 -952 208
WIRE -952 272 -1112 272
WIRE 1192 272 1192 224
WIRE 840 304 840 240
WIRE -232 320 -232 256
WIRE -1112 336 -1112 272
WIRE 1144 352 1080 352
WIRE 792 384 744 384
WIRE -280 400 -328 400
WIRE -1224 416 -1224 272
WIRE -1160 416 -1224 416
WIRE 1192 432 1192 368
WIRE 1288 432 1192 432
WIRE 840 464 840 400
WIRE 1080 464 1080 352
WIRE 1080 464 840 464
WIRE -1112 480 -1112 432
WIRE 1192 496 1192 432
WIRE 840 528 840 464
WIRE 840 528 744 528
WIRE 1000 528 840 528
WIRE -232 544 -232 416
WIRE -232 544 -328 544
WIRE -72 544 -232 544
WIRE -1160 560 -1272 560
WIRE 1080 576 1080 464
WIRE 1144 576 1080 576
WIRE 744 592 744 528
WIRE 1000 592 1000 528
WIRE -328 608 -328 544
WIRE -72 608 -72 544
WIRE -1112 640 -1112 576
WIRE 1192 640 1192 592
WIRE 696 672 648 672
WIRE 952 672 904 672
WIRE -376 688 -424 688
WIRE -120 688 -168 688
WIRE 744 752 744 688
WIRE 856 752 744 752
WIRE 1000 752 1000 688
WIRE 1000 752 856 752
WIRE -328 768 -328 704
WIRE -216 768 -328 768
WIRE -72 768 -72 704
WIRE -72 768 -216 768
WIRE 856 784 856 752
WIRE -216 800 -216 768
FLAG -216 -384 0
FLAG -712 -544 0
FLAG -712 -736 Vdd
FLAG -216 -800 Vdd
FLAG -376 -592 A
FLAG -1352 -560 0
FLAG -1352 -752 A
FLAG -1112 64 Vdd
FLAG -1272 272 A
FLAG -856 272 Y
FLAG -1112 640 0
FLAG -952 64 Vdd
FLAG -1272 560 B
FLAG -1016 192 B
FLAG -1000 -560 0
FLAG -1000 -752 B
FLAG -72 -592 Y
FLAG -232 80 Vdd
FLAG -216 800 0
FLAG -328 240 A
FLAG -424 688 A
FLAG -328 400 B
FLAG -168 688 B
FLAG -72 480 Y
FLAG 872 -800 Vdd
FLAG 712 -592 A
FLAG 872 -224 0
FLAG 1032 -800 Vdd
FLAG 712 -304 B
FLAG 968 -672 B
FLAG 1256 -384 0
FLAG 1256 -800 Vdd
FLAG 840 64 Vdd
FLAG 856 784 0
FLAG 744 224 A
FLAG 648 672 A
FLAG 744 384 B
FLAG 904 672 B
FLAG 1288 432 Y
FLAG 1192 640 0
FLAG 1192 224 Vdd
FLAG 1352 -592 Y
SYMBOL nmos -264 -528 R0
SYMATTR InstName M1
SYMATTR Value2 L=0.18u W=1.0e-4
SYMBOL pmos -264 -752 R0
SYMATTR InstName M2
SYMATTR Value2 L=0.18u W=1.0e-4
SYMBOL voltage -712 -688 R0
SYMATTR InstName V1
SYMATTR Value 0.5
SYMBOL voltage -1352 -704 R0
SYMATTR Value PULSE(0 0.5 2m 0 0 2m 4m)
SYMATTR InstName a
SYMBOL nmos -1160 336 R0
SYMATTR InstName M3
SYMATTR Value2 L=0.18u W=1.0e-4
SYMBOL pmos -1160 112 R0
SYMATTR InstName M4
SYMATTR Value2 L=0.18u W=1.0e-4
SYMBOL pmos -1000 112 R0
SYMATTR InstName M5
SYMATTR Value2 L=0.18u W=1.0e-4
SYMBOL nmos -1160 480 R0
SYMATTR InstName M6
SYMATTR Value2 L=0.18u W=1.0e-4
SYMBOL voltage -1000 -704 R0
SYMATTR Value PULSE(0 0.5 4m 0 0 4m 8m)
SYMATTR InstName b
SYMBOL pmos -280 160 R0
SYMATTR InstName M7
SYMATTR Value2 L=0.18u W=1.0e-4
SYMBOL pmos -280 320 R0
SYMATTR InstName M8
SYMATTR Value2 L=0.18u W=1.0e-4
SYMBOL nmos -376 608 R0
SYMATTR InstName M9
SYMATTR Value2 L=0.18u W=1.0e-4
SYMBOL nmos -120 608 R0
SYMATTR InstName M10
SYMATTR Value2 L=0.18u W=1.0e-4
SYMBOL nmos 824 -528 R0
SYMATTR InstName M11
SYMATTR Value2 L=0.18u W=1.0e-4
SYMBOL pmos 824 -752 R0
SYMATTR InstName M12
SYMATTR Value2 L=0.18u W=1.0e-4
SYMBOL pmos 984 -752 R0
SYMATTR InstName M13
SYMATTR Value2 L=0.18u W=1.0e-4
SYMBOL nmos 824 -384 R0
SYMATTR InstName M14
SYMATTR Value2 L=0.18u W=1.0e-4
SYMBOL nmos 1208 -528 R0
SYMATTR InstName M15
SYMATTR Value2 L=0.18u W=1.0e-4
SYMBOL pmos 1208 -752 R0
SYMATTR InstName M16
SYMATTR Value2 L=0.18u W=1.0e-4
SYMBOL pmos 792 144 R0
SYMATTR InstName M17
SYMATTR Value2 L=0.18u W=1.0e-4
SYMBOL pmos 792 304 R0
SYMATTR InstName M18
SYMATTR Value2 L=0.18u W=1.0e-4
SYMBOL nmos 696 592 R0
SYMATTR InstName M19
SYMATTR Value2 L=0.18u W=1.0e-4
SYMBOL nmos 952 592 R0
SYMATTR InstName M20
SYMATTR Value2 L=0.18u W=1.0e-4
SYMBOL nmos 1144 496 R0
SYMATTR InstName M21
SYMATTR Value2 L=0.18u W=1.0e-4
SYMBOL pmos 1144 272 R0
SYMATTR InstName M22
SYMATTR Value2 L=0.18u W=1.0e-4