Version 4 SHEET 1 1240 1212 WIRE -176 -400 -176 -416 WIRE -176 -304 -176 -320 WIRE -176 -208 -176 -240 WIRE -176 -112 -176 -128 WIRE -176 48 -176 32 WIRE -176 144 -176 128 WIRE -144 -240 -176 -240 WIRE -112 144 -176 144 WIRE -112 144 -112 96 WIRE -96 -416 -176 -416 WIRE -96 144 -112 144 WIRE 0 96 -112 96 WIRE 0 144 -32 144 WIRE 0 208 -112 208 WIRE 0 240 -112 240 WIRE 0 320 -112 320 WIRE 256 -208 256 -240 WIRE 256 -112 256 -128 WIRE 256 192 224 192 WIRE 288 -240 256 -240 WIRE 464 48 464 32 WIRE 464 144 464 128 WIRE 528 144 464 144 WIRE 528 144 528 96 WIRE 544 144 528 144 WIRE 640 96 528 96 WIRE 640 144 608 144 WIRE 640 208 528 208 WIRE 640 240 528 240 WIRE 640 320 528 320 WIRE 688 -208 688 -240 WIRE 688 -112 688 -128 WIRE 720 -240 688 -240 WIRE 896 192 864 192 FLAG -176 -304 0 FLAG -96 -416 VCC FLAG -176 -112 0 FLAG -144 -240 in_b FLAG -176 32 VCC FLAG 256 192 q123 FLAG -112 240 in_b FLAG 256 -112 0 FLAG 288 -240 in_a FLAG -112 208 in_a FLAG 688 -112 0 FLAG 720 -240 in_c FLAG -112 320 in_c FLAG 464 32 VCC FLAG 896 192 q221 FLAG 528 240 in_b FLAG 528 208 in_a FLAG 528 320 in_c SYMBOL voltage -176 -416 R0 SYMATTR InstName V1 SYMATTR Value 5V SYMBOL voltage -176 -224 R0 WINDOW 123 0 0 Left 0 WINDOW 39 0 0 Left 0 SYMATTR InstName V2 SYMATTR Value PULSE(0 5 5u 10n 10n 30u 40u) SYMBOL res -192 32 R0 SYMATTR InstName R3 SYMATTR Value 10k SYMBOL cap -96 160 R270 WINDOW 0 32 32 VTop 0 WINDOW 3 0 32 VBottom 0 SYMATTR InstName C2 SYMATTR Value 1n SYMBOL voltage 256 -224 R0 WINDOW 123 0 0 Left 0 WINDOW 39 0 0 Left 0 SYMATTR InstName V3 SYMATTR Value PULSE(0 5 20u 10n 10n 3u 70u) SYMBOL voltage 688 -224 R0 WINDOW 123 0 0 Left 0 WINDOW 39 0 0 Left 0 SYMATTR InstName V4 SYMATTR Value PULSE(5 0 48u 10n 10n 1u 1) SYMBOL res 448 32 R0 SYMATTR InstName R1 SYMATTR Value 10k SYMBOL cap 544 160 R270 WINDOW 0 32 32 VTop 0 WINDOW 3 0 32 VBottom 0 SYMATTR InstName C1 SYMATTR Value 1n SYMBOL 74hc221A 752 32 R0 SYMATTR InstName U1 SYMATTR SpiceLine VCC=5 SPEED=1.0 TRIPDT=10e-9 SYMBOL 74hc123A 112 32 R0 SYMATTR InstName U2 SYMATTR SpiceLine VCC=5 SPEED=1.0 TRIPDT=10e-9 TEXT -216 -624 Left 0 !.include 74hc.lib TEXT -216 -504 Left 0 !.tran 120u TEXT -216 -648 Left 0 ;Libraries TEXT -216 -528 Left 0 ;Simulation TEXT 72 -560 Left 0 ;Right click with the mouse on the symbol to see the properties.\n \n SpiceModel VCC 0 \n SpecLine VCC=5 SPEED=1 TRIPDTV=1e-9 \n \nVCC 0 +supply net is VCC, - supply net is 0(GND)\nVCC=5 is the value of supply voltage\nSPEED=1 delay multiplier\nTRIPDTV=1e-9 internal timestep for A elements\n Increased to 10e-9 for faster simulation in this example! TEXT 72 -648 Left 0 ;Watch the different behaviour of a 74HC123 and 74HC221 \nwhen double triggered with the falling edge of "in_a" at t=93us. TEXT 40 -8 Left 0 ;Retriggerable TEXT 672 0 Left 0 ;Non-Retriggerable