Datasheet

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MM74HCT138
Truth Table
H = HIGH Level
L = LOW Level
X = Don’t Care
Note 1: G2
= G2A + G2B
Logic Diagram
Inputs Outputs
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G1 G2
(Note 1)
C B A Y0 Y1 Y2 Y3 Y4 Y5 Y6 Y7
X H XXXHHHHHHHH
L X XXXHHHHHHHH
H L LLLLHHHHHHH
H L L LHHLHHHHHH
H L LHLHHLHHHHH
H L LHHHHHLHHHH
H L HL LHHHHLHHH
H L HLHHHHHHLHH
H L HHLHHHHHHLH
H L HHHHHHHHHHL