MC74HC138A
1-of-8 Decoder/
Demultiplexer
HighPerformance SiliconGate CMOS
The MC74HC138A is identical in pinout to the LS138. The device
MC74HC138A
1 15
A0 Y0
ADDRESS 14
2
Y1
A1
A0 1 16 INPUTS
V 13
CC
Y2
3
12
2 15
A1 Y0 A2
ACTIVE-LOW
Y3
11
OUTPUTS
3 14 Y1 Y4
A2
10
Y5
CS2 4 13 Y2
9
Y6
CS3 5 12 Y3
7
Y7
6 11
CS1 Y4
6
Y7 7 10 Y5
CS1
CHIP- PIN 16 = V
CC
4
GND 8 9 Y6
SELECT CS2 PIN 8 = GND
INPUTS
5
CS3
Figure 1. Pin Assignment
Figure 2. Logic Diagram
FUNCTION TABLE
Inputs Outputs
CS1CS2 CS3 A2 A1 A0 Y0 Y1 Y2 Y3 Y4 Y5 Y6 Y7
X X H X X X HHH HHHH H
X H X X X X HHH HHHH H
L X X X X X HHH HHHH H
H L L L L L L H H HHHH H
H L L L L H H L H HHHH H
H L L L H L HH L HHHH H
H L L L H H HHH L HHH H
H L L H L L HHH H L HH H
H L L H L H HHH HH L H H
H L L H H L HHH HHH L H
H L L H H H HHH HHHH L
H = high level (steady state); L = low level (steady state); X = dont care
ORDERING INFORMATION
Device Package Shipping
MC74HC138ANG PDIP16 500 Units / Rail
(Pb Free)
MC74HC138ADG SOIC16 48 Units / Rail
(Pb Free)
MC74HC138ADR2G SOIC16 2500 / Tape & Reel
(Pb Free)
MC74HC138ADTR2G TSSOP16 2500 / Tape & Reel
(Pb Free)
NLV74HC138ADR2G* SOIC16 2500 / Tape & Reel
(Pb Free)
NLV74HC138ADTR2G* TSSOP16 2500 / Tape & Reel
(Pb Free)
For information on tape and reel specifications, including part orientation and tape sizes, please refer to our Tape and Reel Packaging
Specifications Brochure, BRD8011/D.
*NLV Prefix for Automotive and Other Applications Requiring Unique Site and Control Change Requirements; AECQ100 Qualified and PPAP
Capable