TI SN74ALS155

SN74ALS155
DUAL 2-LINE TO 4-LINE DECODER/DEMULTIPLEXER
SDAS140 — NOVEMBER 1987
•
•
•
D or N Package
(Top View)
Applications:
Dual 2-Line to 4-Line Decoder
Dual 1-Line to 4-Line Demultiplexer
3-Line to 8-Line Decoder
1-Line to 8-Line Demultiplexer
1C
1G
B
1Y3
1Y2
1Y1
1Y0
GND
Individual Strobes Simplify Cascading For
Decoding or Demultiplexing Larger Words
Package Options Include Plastic “Small
Outline” Packages and Standard Plastic
300-mil DIPs
1
16
2
15
3
14
4
13
5
12
6
11
7
10
8
9
VCC
2C
2G
A
2Y3
2Y2
2Y1
2Y0
description
The ′ALS155 circuits feature dual 1-line to 4-line
demultiplexers with individual strobes and
common binary-address inputs in a single 16-pin
package. When both sections are enabled, the
common binary-address inputs sequentially
select and route associated input data to the
appropriate output of each section. The individual
strobes permit enabling or disabling each of the
4-bit sections as desired.
Data applied to input 1C is inverted at its outputs
and data applied at input 2C is not inverted
through its outputs. The inverter following the 1C
data input permits use of the ′ALS155 as a 3-line
to 8-line demultiplexer without external gating. All
inputs are clamped with high-performance
Schottky diodes to suppress line ringing and
simplify system design.
The SN74ALS155 is characterized for operation
from 0°C to 70°C.
logic diagram (positive logic)
STROBE 2
1G
DATA 1
1C
SELECT 3
B
7 OUTPUT
1Y0
6 OUTPUT
1Y1
5 OUTPUT
1Y2
4 OUTPUT
1Y3
SELECT 13
A
9 OUTPUT
2Y0
10 OUTPUT
2Y1
DATA 15
2C
STROBE 14
1G
11 OUTPUT
2Y2
12 OUTPUT
2Y3
Copyright  1987, Texas Instruments Incorporated
PRODUCTION DATA information is 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.
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
1
SN74ALS155
DUAL 2-LINE TO 4-LINE DECODER/DEMULTIPLEXER
SDAS140 — NOVEMBER 1987
logic symbols† (alternatives)
FUNCTION TABLE
2-LINE TO 4-LINE DECODER
OR
2-LINE TO 4-LINE DECODER
1-LINE TO 4-LINE DEMULTIPLEXER
X/Y
1G
1C
A
B
2G
2C
&
2
EN α
1
13
3
1
14
0α
1α
2α
3α
0β
2
&
EN β
15
7
1Y0
6
1Y1
5
1Y2
4 1Y3
1β
2β
3β
INPUTS
SELECT
9
2Y0
10
2Y1
11
2Y2
12
2Y3
1-LINE TO 4-LINE DEMULTIPLEXER
A
B
13
3
0
G0
3
1
1C
2G
2C
2
A
1Y0
1Y1
1Y2
1Y3
X
L
H
H
L
L
X
H
H
H
L
H
H
H
L
H
H
H
H
H
H
H
H
X
L
H
X
L
L
X
H
H
L
H
H
H
H
H
H
L
H
H
H
L
H
INPUTS
G4
1
B
X
L
L
SELECT
DMUX
1G
4
0
1
2
3
14
15
7
6
5
4
9
10
11
12
1Y0
1Y1
1Y2
1Y3
2Y0
2Y1
2Y2
2Y3
X/Y
A
B
C
G
3
1
0
1
2
3
4
5
6
7
1
2
15
2
4
14
EN
B
A
2Y0
2Y1
2Y2
2Y3
X
L
L
X
L
H
H
L
L
X
L
L
H
L
H
H
H
L
H
H
H
H
H
H
H
H
X
L
H
X
L
L
X
L
L
H
H
H
H
H
H
H
L
H
H
H
L
H
A
B
C
G
13
3
0
G0
7
1
15
2
14
2
9
10
11
12
7
6
5
4
2Y0
2Y1
2Y2
2Y3
1Y0
1Y1
1Y2
1Y3
0
1
2
3
9
2Y0
10
2Y1
11
2Y2
12
2Y3
4
5
6
7
7
1Y0
6
1Y1
5
1Y2
4
1Y3
1-LINE TO 8-LINE DEMULTIPLEXER
INPUTS
OUTPUTS
C‡
B
A
STROBE
OR DATA
G§
X
L
L
X
L
L
X
L
H
H
L
L
H
L
H
H
H
L
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
L
L
H
H
H
H
L
L
L
H
L
H
L
L
L
L
H
H
H
H
H
H
H
H
L
H
H
H
H
L
H
H
H
H
L
H
H
H
H
L
H
H
H
H
H
H
H
H
H
H
H
H
L
H
L
L
H
H
H
H
H
H
H
H
H
H
H
H
L
H
H
L
SELECT
(0)
(1)
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
(2)
(3)
(4)
(5)
(6)
(7)
2Y0 2Y1 2Y2 2Y3 1Y0 1Y1 1Y2 1Y3
‡ C = inputs 1C and 2C connected together
§ G = inputs 1G and 2G connected together
† These symbols are in accordance with ANSI/IEEE Std 91-1984
and IEC Publication 617-12.
2
DATA
2C
FUNCTION TABLE
3-LINE TO 8-LINE DECODER
OR
1-LINE TO 8-LINE DEMULTIPLEXER
DMUX
OUTPUTS
STROBE
2G
3-LINE TO 8-LINE DECODER
13
OUTPUTS
DATA
1C
STROBE
1G
SN74ALS155
DUAL 2-LINE TO 4-LINE DECODER/DEMULTIPLEXER
SDAS140 — NOVEMBER 1987
absolute maximum ratings over operating free-air temperature range (unless otherwise noted)†
Supply voltage, VCC (see Note 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 V
Input voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 V
Operating free-air temperature range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0°C to 70°C
Storage temperature range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . – 65°C to 150°C
† Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. This is a stress rating only, and
functional operation of the device at these or any other conditions beyond those indicated in the “Recommended Operating Conditions” section of
this specification is not implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
NOTE 1: All voltage values are with respect to GND.
recommended operating conditions
VCC
VIH
Supply voltage
VIL
IOH
Low-level input voltage
IOL
TA
Low-level output current
High-level input voltage
MIN
NOM
MAX
4.5
5
5.5
2
V
V
0.8
High-level output current
Operating free-air temperature
UNIT
V
– 0.4
mA
8
mA
70
°C
0
electrical characteristics over recommended free-air temperature range (unless otherwise noted)
PARAMETER
TEST CONDITIONS
MIN
VIK
VOH
VCC = 4.5 V,
VCC = 4.5 V to 5.5 V,
II = – 18 mA
IOH = – 0.4 mA
VOL
II
VCC = 4.5 V,
VCC = 5.5 V,
IOL = 8 mA
VI = 7 V
IIH
IL
VCC = 5.5 V,
VCC = 5.5 V,
VI = 2.7 V
VI = 0.4 V
ICCL
VCC = 5.5 V,
TYP†
MAX
UNIT
– 1.5
V
VCC – 2
V
0.35
0.5
V
0.1
mA
20
µA
– 0.1
µA
13
mA
7
† All typical value are at VCC = 5 V, TA = 25°C.
switching characteristics over recommended ranges of supply voltage and operating free-air
temperature (see Note 2)
PARAMETER
FROM
(INPUT)
TO
(OUTPUT)
tPLH
tPHL
A, B
tPLH
tPHL
1C
1Y
tPLH
tPHL
1G
1Y
tPLH
tPHL
2C, 2G
1Y, 2Y
2Y
VCC = 4.5 V to 5.5 V,
CL = 50 pF,
RL = 500 Ω,
UNIT
TA = 0°C to 70°C
MIN
MAX
3
14
3
12
3
12
3
14
3
12
3
13
3
12
3
14
ns
ns
ns
ns
NOTE 2: Load circuits and voltage waveforms are shown in Section 1, ALS/AS Logic Data Book, 1986.
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Copyright  1998, Texas Instruments Incorporated