* SPICE netlist
M1 N001 N004 N007 N002 PMOS
M2 N001 N005 N008 N003 PMOS
M3 N007 N006 Vout N009 PMOS
M4 N008 N012 Vout N010 PMOS
M5 N011 N006 N004 N011 PMOS
M6 N004 N006 0 0 NMOS
V2 N011 0 5
V1 N001 0 5
V3 N006 0 PULSE(0 5 0 5n 5n 40m 80m)
V4 N005 0 PULSE(0 5 0 5n 5n 20m 40m)
M7 N013 N005 N012 N013 PMOS
M8 N012 N005 0 0 NMOS
V5 N013 0 5
M9 Vout N004 N016 N014 NMOS
M10 N016 N005 0 N018 NMOS
M11 Vout N006 N017 N015 NMOS
M12 N017 N012 0 N019 NMOS
.tran 80m

* LTspice schematic (.asc)
Version 4
SHEET 1 1552 1328
WIRE 72 -584 -40 -584
WIRE 216 -584 72 -584
WIRE -40 -536 -40 -568
WIRE 216 -536 216 -568
WIRE -312 -504 -312 -520
WIRE -184 -504 -312 -504
WIRE -88 -504 -184 -504
WIRE 168 -472 168 -504
WIRE 568 -472 168 -472
WIRE -536 -376 -696 -376
WIRE -248 -376 -536 -376
WIRE 568 -376 568 -472
WIRE 584 -376 568 -376
WIRE 600 -376 584 -376
WIRE -40 -360 -40 -488
WIRE 216 -360 216 -488
WIRE -40 -312 -40 -344
WIRE 216 -312 216 -344
WIRE 424 -296 408 -296
WIRE -248 -280 -248 -376
WIRE -248 -280 -264 -280
WIRE -120 -280 -248 -280
WIRE -88 -280 -88 -296
WIRE -88 -280 -120 -280
WIRE -72 -280 -88 -280
WIRE -376 -264 -392 -264
WIRE 72 -264 -40 -264
WIRE 216 -264 72 -264
WIRE 408 -248 408 -296
WIRE 424 -248 408 -248
WIRE -376 -216 -376 -264
WIRE -376 -216 -392 -216
WIRE 168 -168 168 -280
WIRE 360 -168 168 -168
WIRE 424 -168 424 -200
WIRE 424 -168 360 -168
WIRE 472 -168 472 -280
WIRE 568 -168 568 -376
WIRE 568 -168 472 -168
WIRE -536 -136 -536 -376
WIRE -440 -136 -440 -184
WIRE -440 -136 -536 -136
WIRE -392 -136 -392 -168
WIRE -312 -136 -312 -504
WIRE -312 -136 -392 -136
WIRE 424 -136 424 -168
WIRE 472 -120 472 -168
WIRE -392 -104 -392 -136
WIRE 424 -88 408 -88
WIRE -376 -56 -392 -56
WIRE 408 -40 408 -88
WIRE 424 -40 408 -40
WIRE -440 -24 -440 -136
WIRE -376 -8 -376 -56
WIRE -376 -8 -392 -8
WIRE 72 136 72 -264
WIRE 776 136 72 136
WIRE -120 168 -120 -280
WIRE 8 168 -120 168
WIRE 72 216 72 136
WIRE 72 216 -56 216
WIRE 264 216 72 216
WIRE -184 296 -184 -504
WIRE -104 296 -184 296
WIRE -56 296 -56 264
WIRE 264 296 264 264
WIRE 8 344 8 168
WIRE 216 344 216 296
WIRE 216 344 8 344
WIRE -56 392 -56 312
WIRE 264 392 264 312
WIRE -56 472 -56 440
WIRE 264 472 264 440
WIRE 88 488 -56 488
WIRE 264 488 88 488
WIRE 216 584 216 472
WIRE 360 584 360 -168
WIRE 360 584 216 584
WIRE 376 584 360 584
WIRE -104 664 -104 472
WIRE 584 664 584 -376
WIRE 584 664 -104 664
FLAG -376 -8 0
FLAG -392 -344 0
FLAG 72 -664 0
FLAG 680 -376 0
FLAG -776 -376 0
FLAG 408 -296 0
FLAG 424 40 0
FLAG 776 136 Vout
IOPIN 48 400 Out
FLAG 88 488 0
DATAFLAG -160 -112 ""
SYMBOL pmos4 -88 -584 R0
SYMATTR InstName M1
SYMBOL pmos4 168 -584 R0
SYMATTR InstName M2
SYMBOL pmos4 -88 -360 R0
SYMATTR InstName M3
SYMBOL pmos4 168 -360 R0
SYMATTR InstName M4
SYMBOL pmos4 -440 -264 R0
SYMATTR InstName M5
SYMBOL nmos4 -440 -104 R0
SYMATTR InstName M6
SYMBOL voltage -392 -248 R180
SYMATTR InstName V2
SYMATTR Value 5
SYMBOL voltage 72 -568 R180
SYMATTR InstName V1
SYMATTR Value 5
SYMBOL voltage -680 -376 R90
SYMATTR InstName V3
SYMATTR Value PULSE(0 5 0 5n 5n 40m 80m)
SYMBOL voltage 584 -376 R270
SYMATTR InstName V4
SYMATTR Value PULSE(0 5 0 5n 5n 20m 40m)
SYMBOL pmos4 472 -40 R180
SYMATTR InstName M7
SYMBOL nmos4 472 -200 R180
SYMATTR InstName M8
SYMBOL voltage 424 -56 R0
SYMATTR InstName V5
SYMATTR Value 5
SYMBOL nmos4 -104 216 R0
SYMATTR InstName M9
SYMBOL nmos4 -104 392 R0
SYMATTR InstName M10
SYMBOL nmos4 216 216 R0
SYMATTR InstName M11
SYMBOL nmos4 216 392 R0
SYMATTR InstName M12