* SPICE netlist
M1 N005 B1 0 0 2N7002
M2 N004 N003 0 0 2N7002
M3 N006 EN B1 B1 2N7002
M4 N006 EN BIT BIT 2N7002
M5 EN X N007 N007 2N7002
M6 N007 Y 0 0 2N7002
R1 N001 EN {R}
VB N001 0 {VB}
VCC N002 0 {VCC}
VX X 0 PULSE({VCC} 0 0 10n 10n 2u 4u 10)
VWR BIT 0 PULSE(0 {VCC} 2u 10n 10n 1.5u 8u 10)
VY Y 0 PULSE({VCC} 0 1u 10n 10n 2u 4u 10)
R3 B1 N004 R=R/2
R4 N005 N003 R=R/2
M7 N005 B1 N002 N002 BSS84
M8 N004 N003 N002 N002 BSS84
.param VCC=3.3 R=500 VB=5
.tran 100u

* LTspice schematic (.asc)
Version 4
SHEET 1 2128 1072
WIRE 1064 -536 -504 -536
WIRE 1064 -488 1064 -536
WIRE 504 -344 56 -344
WIRE 760 -344 504 -344
WIRE 56 -296 56 -344
WIRE 504 -296 504 -344
WIRE 248 -280 104 -280
WIRE 456 -280 328 -280
WIRE -504 -264 -504 -536
WIRE -504 -136 -504 -184
WIRE -440 -136 -504 -136
WIRE -360 -136 -440 -136
WIRE -120 -136 -360 -136
WIRE 56 -104 56 -200
WIRE 104 -104 56 -104
WIRE 328 -104 328 -280
WIRE 328 -104 184 -104
WIRE -360 -72 -360 -136
WIRE -120 -72 -120 -136
WIRE 248 -56 248 -280
WIRE 408 -56 248 -56
WIRE 504 -56 504 -200
WIRE 504 -56 488 -56
WIRE -440 -24 -1064 -24
WIRE -376 -24 -440 -24
WIRE -200 -24 -280 -24
WIRE -24 -24 -104 -24
WIRE 328 -24 328 -104
WIRE 328 -24 -24 -24
WIRE 760 -8 760 -344
WIRE -696 72 -920 72
WIRE -600 72 -696 72
WIRE -696 120 -776 120
WIRE -648 120 -696 120
WIRE -504 152 -504 -136
WIRE 56 152 56 -104
WIRE 504 152 504 -56
WIRE -1064 184 -1064 -24
WIRE -920 184 -920 72
WIRE -776 184 -776 120
WIRE -600 232 -600 72
WIRE -552 232 -600 232
WIRE 248 232 248 -56
WIRE 248 232 104 232
WIRE 328 232 328 -24
WIRE 456 232 328 232
WIRE -504 312 -504 248
WIRE -648 392 -648 120
WIRE -552 392 -648 392
WIRE -1064 472 -1064 264
WIRE -920 472 -920 264
WIRE -920 472 -1064 472
WIRE -776 472 -776 264
WIRE -776 472 -920 472
WIRE -504 472 -504 408
WIRE -504 472 -776 472
WIRE 56 472 56 248
WIRE 56 472 -504 472
WIRE 136 472 56 472
WIRE 504 472 504 248
WIRE 504 472 136 472
WIRE 760 472 760 72
WIRE 760 472 504 472
WIRE 1064 472 1064 -408
WIRE 1064 472 760 472
WIRE 136 536 136 472
FLAG 136 536 0
FLAG -24 -24 B1
FLAG -440 -24 BIT
FLAG -440 -136 EN
FLAG -696 72 X
FLAG -696 120 Y
SYMBOL nmos 456 152 R0
SYMATTR InstName M1
SYMATTR Value 2N7002
SYMBOL nmos 104 152 M0
SYMATTR InstName M2
SYMATTR Value 2N7002
SYMBOL nmos -200 -72 M90
SYMATTR InstName M3
SYMATTR Value 2N7002
SYMBOL nmos -280 -72 R90
SYMATTR InstName M4
SYMATTR Value 2N7002
SYMBOL nmos -552 152 R0
SYMATTR InstName M5
SYMATTR Value 2N7002
SYMBOL nmos -552 312 R0
SYMATTR InstName M6
SYMATTR Value 2N7002
SYMBOL res -520 -280 R0
SYMATTR InstName R1
SYMATTR Value {R}
SYMBOL voltage 1064 -504 R0
SYMATTR InstName VB
SYMATTR Value {VB}
SYMBOL voltage 760 -24 R0
SYMATTR InstName VCC
SYMATTR Value {VCC}
SYMBOL voltage -920 168 R0
SYMATTR InstName X
SYMATTR Value PULSE({VCC} 0 0 10n 10n 2u 4u 10)
SYMBOL voltage -1064 168 R0
SYMATTR InstName WR
SYMATTR Value PULSE(0 {VCC} 2u 10n 10n 1.5u 8u 10)
SYMBOL voltage -776 168 R0
SYMATTR InstName Y
SYMATTR Value PULSE({VCC} 0 1u 10n 10n 2u 4u 10)
SYMBOL res 200 -120 R90
SYMATTR InstName R3
SYMATTR Value R=R/2
SYMBOL res 504 -72 R90
SYMATTR InstName R4
SYMATTR Value R=R/2
SYMBOL pmos 456 -200 M180
SYMATTR InstName M7
SYMATTR Value BSS84
SYMBOL pmos 104 -200 R180
SYMATTR InstName M8
SYMATTR Value BSS84