
1
Data sheet acquired from Harris Semiconductor
SCHS234
Features
CD74AC138, CD74ACT138 . . . . . . . . . . . . . . . Inverting
CD74AC238, CD74ACT238 . . . . . . . . . . . Non-Inverting
Buffered Inputs
Typical Propagation Delay
- 5ns at V
CC
= 5V, T
A
= 25
o
C, C
L
= 50pF
Exceeds 2kV ESD Protection MIL-STD-883, Method
3015
SCR-Latchup-Resistant CMOS Process and Circuit
Design
Speed of Bipolar FAST/AS/S with Significantly
Reduced Power Consumption
Balanced Propagation Delays
AC Types Feature 1.5V to 5.5V Operation and
Balanced Noise Immunity at 30% of the Supply
±
24mA Output Drive Current
- Fanout to 15 FAST ICs
- Drives 50
Transmission Lines
Pinout
CD74AC138, CD74ACT138, CD74AC238, CD74ACT238
(PDIP, SOIC)
TOP VIEW
Description
The
CD74ACT238 are 3-to-8-line decoders/demultiplexers that
utilize the Harris Advanced CMOS Logic technology. Both
circuits have three binary select inputs (A0, A1, and A2). If
the device is enabled, these inputs determine which one of
the eight normally HIGH outputs of the AC/ACT138 will go
LOW or which on of the normally LOW outputs of the
AC/ACT238 will go HIGH. Two active LOW and one active
HIGH enables (E1, E2 and E3) are provided to simplify the
cascading of these devices.
CD74AC138,
CD74ACT138,
CD74AC238,
and
14
15
16
9
13
12
11
10
1
2
3
4
5
7
6
8
A0
A1
A2
E1
E2
E3
GND
AC/ACT138 Y7
AC/ACT238 Y7
V
CC
Y0 AC/ACT138
Y0 AC/ACT238
Y1 AC/ACT138
Y1 AC/ACT238
Y2 AC/ACT138
Y2 AC/ACT238
Y3 AC/ACT138
Y3 AC/ACT238
Y4 AC/ACT138
Y4 AC/ACT238
Y5 AC/ACT138
Y5 AC/ACT238
Y6 AC/ACT138
Y6 AC/ACT238
Ordering Information
PART
NUMBER
TEMP.
RANGE (
o
C)
0 to 70
o
C, -40 to 85,
-55 to 125
0 to 70
o
C, -40 to 85,
-55 to 125
0 to 70
o
C, -40 to 85,
-55 to 125
0 to 70
o
C, -40 to 85,
-55 to 125
0 to 70
o
C, -40 to 85,
-55 to 125
0 to 70
o
C, -40 to 85,
-55 to 125
0 to 70
o
C, -40 to 85,
-55 to 125
0 to 70
o
C, -40 to 85,
-55 to 125
PACKAGE
PKG.
NO.
CD74AC138E
16 Ld PDIP
E16.3
CD74ACT138E
16 Ld PDIP
E16.3
CD74AC238E
16 Ld PDIP
E16.3
CD74ACT238E
16 Ld PDIP
E16.3
CD74AC138M
16 Ld SOIC
M16.15
CD74ACT138M
16 Ld SOIC
M16.15
CD74AC238M
16 Ld SOIC
M16.15
CD74ACT238M
16 Ld SOIC
M16.15
NOTES:
17. When ordering, use the entire part number. Add the suffix 96 to
obtain the variant in the tape and reel.
18. Wafer and die for this part number is available which meets all elec-
trical specifications. Please contact your local sales office or Harris
customer service for ordering information.
September 1998
CAUTION: These devices are sensitive to electrostatic discharge. Users should follow proper IC Handling Procedures.
FAST is a Trademark of Fairchild Semiconductor.
Copyright
Harris Corporation 1998
CD74AC138, CD74ACT138,
CD74AC238, CD74ACT238
3-to-8-Line Decoders/Demultiplexers
File Number
1909.1
[ /Title
(CD74
AC138
,
CD74
ACT13
8,
CD74
AC238
,
CD74
ACT23
8)
/Sub-
ject (3-
to-8-
Line
Decod-
ers/De
multi-
plex-
ers)
/Autho
r ()
/Key-
words
(Har-
ris
Semi-
con-
ductor,
Advan
ced