Diodes 74HCT138 - Manual (Page 2)

74HCT138
Document number: DS35489 Rev. 3 - 2
2 of 10
www.diodes.com
June 2013
© Diodes Incorporated
74HCT138
Pin Descriptions
Pin Number Pin Name Description
1 A0 Address Input 0
2 A1 Address Input 1
3 A2 Address Input 2
4 E1 Enable Input 1 (active LOW)
5 E2 Enable Input 2 (active LOW)
6 E3 Enable Input 3 (active HIGH)
7 Y7 Output 7 (active LOW)
8 GND Ground
9 Y6 Output 6 (active LOW)
10 Y5 Output 5 (active LOW)
11 Y4 Output 4 (active LOW)
12 Y3 Output 3 (active LOW)
13 Y2 Output 2 (active LOW)
14 Y1 Output 1 (active LOW)
15 Y0 Output o (active LOW)
16 V
cc
Supply Voltage
Function Table Diagram
Control Input Output
E1 E2 E3 A2 A1 A0 Y7 Y6 Y5 Y4 Y3 Y2 Y1 Y0
H X X X X X H H H H H H H H
X H X           
X X L           
L L H           
   L L L H H H H H H H L
   L L H H H H H H H L H
   L H L H H H H H L H H
   L H H H H H H L H H H
   H L L H H H L H H H H
   H L H H H L H H H H H
   H H L H L H H H H H H
   H H H L H H H H H H H