74ACT139

MC74AC139 MC74ACT139 Dual 1ĆofĆ4 Decoder/Demultiplexer The MC74AC139/74ACT139 is a high-speed, dual 1-of-4 decoder/demultiplexer. The device has two independent decoders, each accepting two inputs and providing four mutually-exclusive active-LOW outputs. Each decoder has an active-LOW Enable input which can be used as a data input for a 4-output demultiplexer. Each half of the MC74AC139/74ACT139 can be used as a function generator providing four minterms of two variables. Multifunction Capability Two Completely Independent 1-of-4 Decoders Active LOW Mutually Exclusive Outputs Outputs Source/Sink 24 mA ′ACT139 Has TTL Compatible Inputs VCC 16 Eb 15 A0b 14 A1b 13 O0b 12 O1b 11 O2b 10 O3b 9 DUAL 1-OF-4 DECODER/DEMULTIPLEXER N SUFFIX CASE 648-08 PLASTIC PIN NAMES 1 Ea 2 A0a 3 A1a 4 O0a 5 O1a 6 O2a 7 8 O3a GND A0, A1 E O0–O3 Address Inputs Enable Inputs Outputs D SUFFIX CASE 751B-05 PLASTIC TRUTH TABLE Inputs E H L L L L A0 X L H L H A1 X L L H H O0 H L H H H Outputs O1 H H L H H O2 H H H L H O3 H H H H L LOGIC SYMBOL E A0 A1 DECODER a O0 O1 O2 O3 H = HIGH Voltage Level L = LOW Voltage Level X = Immaterial E A0 A1 DECODER b O0 O1 O2 O3 FACT DATA 5-1 MC74AC139 MC74ACT139 LOGIC DIAGRAM Ea A0a A1a Eb A0b A1b 00a 01a 02a 03a 00b 01b 02b 03b Please note that this diagram is provided only for the understanding of logic operations and should not be used to estimate propagation delays. FUNCTIONAL DESCRIPTION The MC74AC139/74ACT139 is a high-speed dual 1-of-4...