SN54HCT139, SN74HCT139
DUAL 2-LINE TO 4-LINE DECODERS/DEMULTIPLEXERS
SCLS066B – MARCH 1982 – REVISED MAY 1997
1
POST OFFICE BOX 655303
DALLAS, TEXAS 75265
D Inputs Are TTL-Voltage Compatible
D Designed Specifically for High-Speed
Memory Decoders and Data Transmission
Systems
D Incorporate Two Enable Inputs to Simplify
Cascading and/or Data Reception
D 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
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.
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
G
SELECT
OUTPUTS
G
B
A
Y0
Y1
Y2
Y3
H
X
H
L
LL
HH
H
L
HH
LH
H
L
H
LH
HLH
L
H
L
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Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
32 1 20 19
910 11 1213
4
5
6
7
8
18
17
16
15
14
2A
2B
NC
2Y0
2Y1
1B
1Y0
NC
1Y1
1Y2
1A
1G
NC
2Y3
2Y2
V
2G
1Y3
GND
NC
SN54HCT139 . . . 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
1G
1A
1B
1Y0
1Y1
1Y2
1Y3
GND
VCC
2G
2A
2B
2Y0
2Y1
2Y2
2Y3
SN54HCT139 ...J OR W PACKAGE
SN74HCT139 . . . D, DB, N, OR PW PACKAGE
(TOP VIEW)
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.