SN54HCT139, SN74HCT139
DUAL 2-LINE TO 4-LINE DECODERS/DEMULTIPLEXERS
SCLS066B – MARCH 1982 – REVISED MAY 1997
SN54HCT139 . . . J OR W PACKAGE
SN74HCT139 . . . D, DB, N, OR PW PACKAGE
(TOP VIEW)
Inputs Are TTL-Voltage Compatible
Designed Specifically for High-Speed
Memory Decoders and Data Transmission
Systems
1G
1A
V
CC
2G
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
Incorporate Two Enable Inputs to Simplify
Cascading and/or Data Reception
1B
2A
1Y0
1Y1
1Y2
1Y3
GND
2B
Package Options Include Plastic
Small-Outline (D), Shrink Small-Outline
(DB), Thin Shrink Small-Outline (PW), and
Ceramic Flat (W) Packages, Ceramic Chip
Carriers (FK), and Standard Plastic (N) and
Ceramic (J) 300-mil DIPs
2Y0
2Y1
2Y2
2Y3
SN54HCT139 . . . FK PACKAGE
(TOP VIEW)
description
The ’HCT139 are designed for high-performance
memory-decoding or data-routing applications
requiring very short propagation delay times. In
high-performance memory systems, these
decoders can minimize the effects of system
decoding. When employed with high-speed
memories utilizing a fast enable circuit, the delay
time 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.
3
2
1
20 19
18
2A
2B
NC
1B
1Y0
NC
4
5
6
7
8
17
16
15 2Y0
14
9 10 11 12 13
1Y1
1Y2
2Y1
NC – No internal connection
The ’HCT139 comprise two individual 2-line to
4-line decoders in a single package. The
active-low enable (G) input can be used as a data
line in demultiplexing applications. These
decoders/demultiplexers feature fully buffered
inputs, each of which represents only one
normalized load to its driving circuit.
The SN54HCT139 is characterized for operation over the full military temperature range of –55°C to 125°C. The
SN74HCT139 is characterized for operation from –40°C to 85°C.
FUNCTION TABLE
INPUTS
OUTPUTS
SELECT
G
B
X
L
A
X
L
Y0
H
L
Y1
H
H
L
Y2
H
H
H
L
Y3
H
H
H
H
L
H
L
L
L
L
L
H
L
H
H
H
H
H
H
H
H
H
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
Copyright 1997, Texas Instruments Incorporated
UNLESS OTHERWISE NOTED this document contains PRODUCTION
DATA information current as of publication date. Products conform to
specifications per the terms of Texas Instruments standard warranty.
Production processing does not necessarily include testing of all
parameters.
1
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