MC74HC138A Datasheet, PDF (1/8 Pages) ON Semiconductor – 1-of-8 Decoder/Demultiplexer

MC74HC138A
1-of-8 Decoder/
Demultiplexer
High–Performance Silicon–Gate CMOS
The MC74HC138A is identical in pinout to the LS138. The device
inputs are compatible with standard CMOS outputs; with pullup
resistors, they are compatible with LSTTL outputs.
The HC138A decodes a three–bit Address to one–of–eight
active–low outputs. This device features three Chip Select inputs, two
active–low and one active–high to facilitate the demultiplexing,
cascading, and chip–selecting functions. The demultiplexing function
is accomplished by using the Address inputs to select the desired
device output; one of the Chip Selects is used as a data input while the
other Chip Selects are held in their active states.
• Output Drive Capability: 10 LSTTL Loads
• Outputs Directly Interface to CMOS, NMOS and TTL
• Operating Voltage Range: 2.0 to 6.0 V
• Low Input Current: 1.0 µA
• High Noise Immunity Characteristic of CMOS Devices
• In Compliance with the Requirements Defined by JEDEC Standard
No. 7A
• Chip Complexity: 100 FETs or 29 Equivalent Gates
LOGIC DIAGRAM
ADDRESS
INPUTS
A0 ¹
A1 ²
A2 ³
15 _Y0
14 _Y1
13 _Y2
12 _Y3
11 _Y4
10
Y5
9 _Y6
7
Y7
ACTIVE–LOW
OUTPUTS
CS1 ⁶
CHIP–
SELECT
CS2
4
INPUTS
CS3
5
PIN 16 = VCC
PIN 8 = GND
FUNCTION TABLE
Inputs
Outputs
CS1CS2 CS3 A2 A1 A0 Y0 Y1 Y2 Y3 Y4 Y5 Y6 Y7
X X H XXX HHH HHHH H
X H X XXX HHH HHHH H
L X X XXX HHH HHHH H
H L L LLL LHHHHHHH
H L L LLHH L HHHHHH
H L L LHL HH L HHHHH
H L L LHH H H H L H H H H
H L L HLL HHHH L HHH
H L L HLHHHHHH L HH
H L L HHL H H H H H H L H
H L L HHH H H H H H H H L
H = high level (steady state); L = low level (steady state); X = don’t care
© Semiconductor Components Industries, LLC, 2000
1
March, 2000 – Rev. 7
http://onsemi.com
16
1
16
1
PDIP–16
N SUFFIX
CASE 648
SO–16
D SUFFIX
CASE 751B
MARKING
DIAGRAMS
16
MC74HC138AN
AWLYYWW
1
16
HC138A
AWLYWW
1
16
16
1
TSSOP–16
DT SUFFIX
CASE 948F
HC
138A
ALYW
1
A = Assembly Location
WL = Wafer Lot
YY = Year
WW = Work Week
PIN ASSIGNMENT
A0 1
A1 2
A2 3
CS2 4
CS3 5
CS1 6
Y7 7
GND 8
16 VCC
15 Y0
14 Y1
13 Y2
12 Y3
11 Y4
10 Y5
9 Y6
ORDERING INFORMATION
Device
Package Shipping
MC74HC138AN
PDIP–16 2000 / Box
MC74HC138AD
SOIC–16
48 / Rail
MC74HC138ADR2
SOIC–16 2500 / Reel
MC74HC138ADT
TSSOP–16 96 / Rail
MC74HC138ADTR2 TSSOP–16 2500 / Reel
Publication Order Number:
MC74HC138A/D