Datasheet

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MM74HC138
Truth Table
H = HIGH Level, L = LOW Level, X = don’t care
Note 1: G2
= G2A+G2B
Logic Diagram
Inputs Outputs
Enable Select
G1 G2
(Note 1) C B A Y0Y1Y2Y3Y4Y5Y6Y7
X H XXXHHHHHHHH
L X XXXHHHHHHHH
H L LL L LHHHHHHH
H L LLHHLHHHHHH
H L LHLHHLHHHHH
H L LHHHHHLHHHH
H L HLLHHHHLHHH
H L HLHHHHHHLHH
H L HHLHHHHHHLH
H L HHHHHHHHHHL