SCLS107E − DECEMBER 1982 − REVISED SEPTEMBER 2003
1
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
D Targeted Specifically for High-Speed
Memory Decoders and Data-Transmission
Systems
D Wide Operating Voltage Range of 2 V to 6 V
D Outputs Can Drive Up To 10 LSTTL Loads
D Low Power Consumption, 80-µA Max I
CC
D Typical t
pd
= 15 ns
D ±4-mA Output Drive at 5 V
D Low Input Current of 1 µA Max
D Incorporate Three Enable Inputs to Simplify
Cascading and/or Data Reception
description/ordering information
The ’HC138 devices are designed to be used in
high-performance memory-decoding or data-
routing applications requiring very short
propagation delay times. In high-performance
memory systems, these decoders can be used to
minimize the effects of system decoding. When
employed with high-speed memories utilizing a
fast enable circuit, the delay times of these
decoders and the enable time of the memory are
usually less than the typical access time of the
memory. This means that the effective system
delay introduced by the decoders is negligible.
ORDERING INFORMATION
T
A
PACKAGE
†
ORDERABLE
PART NUMBER
TOP-SIDE
MARKING
PDIP − N Tube of 25 SN74HC138N SN74HC138N
Tube of 40 SN74HC138D
SOIC − D
Reel of 2500 SN74HC138DR
HC138
Reel of 250 SN74HC138DT
−40°C to 85°C
SOP − NS Reel of 2000 SN74HC138NSR HC138
SSOP − DB Reel of 2000 SN74HC138DBR HC138
Tube of 90 SN74HC138PW
TSSOP − PW
Reel of 2000 SN74HC138PWR
HC138
Reel of 250 SN74HC138PWT
CDIP − J Tube of 25 SNJ54HC138J SNJ54HC138J
−55°C to 125°C
CFP − W Tube of 150 SNJ54HC138W SNJ54HC138W
LCCC − FK Tube of 55 SNJ54HC138FK SNJ54HC138FK
†
Package drawings, standard packing quantities, thermal data, symbolization, and PCB design guidelines are
available at www.ti.com/sc/package.
3212019
910111213
4
5
6
7
8
18
17
16
15
14
Y1
Y2
NC
Y3
Y4
C
G
2A
NC
G
2B
G1
B
A
NC
Y6
Y5
V
Y0
Y7
GND
NC
SN54HC138 . . . FK PACKAGE
(TOP VIEW)
CC
NC − No internal connection
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
A
B
C
G
2A
G
2B
G1
Y7
GND
V
CC
Y0
Y1
Y2
Y3
Y4
Y5
Y6
SN54HC138 ...J OR W PACKAGE
SN74HC138 . . . D, DB, N, NS, OR PW PACKAGE
(TOP VIEW)
Copyright 2003, Texas Instruments Incorporated
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications o
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
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