NSC 74LS155

54LS155/DM54LS155/DM74LS155,
54LS156/DM54LS156/DM74LS156
Dual 2-Line to 4-Line Decoders/Demultiplexers
General Description
Features
These TTL 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 by the strobes, the common address inputs sequentially select and route associated input data to the appropriate output of each section. The individual strobes permit activating or inhibiting each of the 4-bit sections as desired. Data applied to input C1 is inverted at its outputs and
data applied at C2 is true through its outputs. The inverter
following the C1 data input permits use as a 3-to-8-line decoder, or 1-to-8-line demultiplexer, without external gating.
Input clamping diodes are provided on these circuits to minimize transmission-line effects and simplify system design.
Y
Y
Y
Y
Y
Applications:
Dual 2-to-4-line decoder
Dual 1-to-4-line demultiplexer
3-to-8-line decoder
1-to-8-line demultiplexer
Individual strobes simplify cascading for decoding or
demultiplexing larger words
Input clamping diodes simplify system design
Choice of outputs:
Totem-pole (LS155)
Open-collector (LS156)
Alternate Military/Aerospace device (54LS155/156) is
available. Contact a National Semiconductor Sales Office/Distributor for specifications.
Connection Diagram and Function Tables
Dual-In-Line Package
Order Number 54LS155DMQB, 54LS155FMQB,
54LS155LMQB, DM54LS155J, DM54LS155W,
DM74LS155M, DM74LS155N, 54LS156DMQB,
54LS156FMQB, DM54LS156J, DM54LS156W,
DM74LS156M or DM74LS156N
See NS Package Number E20A, J16A,
M16A, N16E or W16A
2-Line-to-4-Line Decoder or
1-Line-to-4-Line Demultiplexer
Inputs
Select
TL/F/6395 – 1
3-Line-to-8-Line Decoder or
1-Line-to-8-Line Demultiplexer
Inputs
C² B A
X
L
L
L
L
H
H
H
H
X
L
L
H
H
L
L
H
H
X
L
H
L
H
L
H
L
H
G³
H
L
L
L
L
L
L
L
L
(1)
(2)
(3)
(4)
A
G1
C1
1Y0
1Y1
1Y2
1Y3
X
L
L
H
H
X
X
L
H
L
H
X
H
L
L
L
L
X
X
H
H
H
H
L
H
L
H
H
H
H
H
H
L
H
H
H
H
H
H
L
H
H
H
H
H
H
L
H
Inputs
(5)
(6)
(7)
2Y0 2Y1 2Y2 2Y3 1Y0 1Y1 1Y2 1Y3
H
L
H
H
H
H
H
H
H
H
H
L
H
H
H
H
H
H
H
H
H
L
H
H
H
H
H
H
H
H
H
L
H
H
H
H
H
H
H
H
H
L
H
H
H
Data
B
Outputs
Strobe
Select
(0)
Or Data
Outputs
Strobe
H
H
H
H
H
H
L
H
H
H
H
H
H
H
H
H
L
H
H
H
H
H
H
H
H
H
L
Select
Outputs
Strobe
Data
B
A
G2
C2
2Y0
2Y1
2Y2
2Y3
X
L
L
H
H
X
X
L
H
L
H
X
H
L
L
L
L
X
X
L
L
L
L
H
H
L
H
H
H
H
H
H
L
H
H
H
H
H
H
L
H
H
H
H
H
H
L
H
² C e inputs C1 and C2 connected together
³ G e inputs G1 and G2 connected together
H e high level, L e low level, X e don’t care
C1995 National Semiconductor Corporation
TL/F/6395
RRD-B30M105/Printed in U. S. A.
54LS155/DM54LS155/DM74LS155,
54LS156/DM54LS156/DM74LS156 Dual 2-Line to 4-Line Decoders/Demultiplexers
June 1989
Absolute Maximum Ratings (Note)
Note: The ‘‘Absolute Maximum Ratings’’ are those values
beyond which the safety of the device cannot be guaranteed. The device should not be operated at these limits. The
parametric values defined in the ‘‘Electrical Characteristics’’
table are not guaranteed at the absolute maximum ratings.
The ‘‘Recommended Operating Conditions’’ table will define
the conditions for actual device operation.
If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales
Office/Distributors for availability and specifications.
Supply Voltage
7V
Input Voltage
7V
Operating Free Air Temperature Range
b 55§ C to a 125§ C
DM54LS and 54LS
DM74LS
0§ C to a 70§ C
Storage Temperature Range
b 65§ C to a 150§ C
Recommended Operating Conditions
Symbol
DM54LS155
Parameter
VCC
Supply Voltage
VIH
High Level Input Voltage
VIL
Low Level Input Voltage
VOH
High Level Output Current
IOL
Low Level Output Current
TA
Free Air Operating Temperature
DM74LS155
Units
Min
Nom
Max
Min
Nom
Max
4.5
5
5.5
4.75
5
5.25
V
0.7
0.8
V
b 0.4
b 0.4
mA
2
2
V
4
b 55
125
0
8
mA
70
§C
Max
Units
b 1.5
V
’LS155 Electrical Characteristics
over recommended operating free air temperature range (unless otherwise noted)
Symbol
Parameter
Conditions
Min
Typ
(Note 1)
VI
Input Clamp Voltage
VCC e Min, II e b18 mA
VOH
High Level Output
Voltage
VCC e Min, IOH e Max
VIL e Max, VIH e Min
DM54
2.5
3.4
DM74
2.7
3.4
Low Level Output
Voltage
VCC e Min, IOL e Max
VIL e Max, VIH e Min
DM54
0.25
0.4
DM74
0.35
0.5
IOL e 4 mA, VCC e Min
DM74
0.25
0.4
VOL
II
Input Current @ Max
Input Voltage
VCC e Max, VI e 7V
IIH
High Level Input Current
IIL
IOS
ICC
V
V
0.1
mA
VCC e Max, VI e 2.7V
20
mA
Low Level Input Current
VCC e Max, VI e 0.4V
b 0.36
mA
Short Circuit
Output Current
VCC e Max
(Note 2)
Supply Current
VCC e Max (Note 3)
DM54
b 20
b 100
DM74
b 20
b 100
Note 1: All typicals are at VCC e 5V, TA e 25§ C.
Note 2: Not more than one output should be shorted at a time, and the duration should not exceed one second.
Note 3: ICC is measured with all outputs open, A,B, and C1 inputs at 4.5V, and C2, G1, and G2 inputs grounded.
2
6.1
10
mA
mA
’LS155 Switching Characteristics
at VCC e 5V and TA e 25§ C (See Section 1 for Test Waveforms and Output Load)
Symbol
RL e 2 kX
From (Input)
To (Output)
Parameter
CL e 15 pF
Min
CL e 50 pF
Max
Min
Units
Max
tPLH
Propagation Delay Time
Low to High Level Output
A, B, C2, G1
or G2 to Y
18
22
ns
tPHL
Propagation Delay Time
High to Low Level Output
A, B, C2, G1
or G2 to Y
27
35
ns
tPLH
Propagation Delay Time
Low to High Level Output
A or B
to Y
18
24
ns
tPHL
Propagation Delay Time
High to Low Level Output
A or B
to Y
27
35
ns
tPLH
Propagation Delay Time
Low to High Level Output
C1
to Y
20
24
ns
tPHL
Propagation Delay Time
High to Low Level Output
C1
to Y
27
35
ns
Recommended Operating Conditions
Symbol
DM54LS156
Parameter
DM74LS156
Units
Min
Nom
Max
Min
Nom
Max
4.5
5
5.5
4.75
5
5.25
VCC
Supply Voltage
VIH
High Level Input Voltage
VIL
Low Level Input Voltage
0.7
0.8
VOH
High Level Output Voltage
5.5
5.5
V
IOL
Low Level Output Current
4
8
mA
TA
Free Air Operating Temperature
70
§C
Max
Units
b 1.5
V
100
mA
2
2
b 55
125
V
V
0
V
’LS156 Electrical Characteristics
over recommended operating free air temperature range (unless otherwise noted)
Symbol
VI
Parameter
Conditions
Min
Typ
(Note 1)
Input Clamp Voltage
VCC e Min, II e b18 mA
ICEX
High Level Output
Current
VCC e Min, VO e 5.5V
VIL e Max, VIH e Min
VOL
Low Level Output
Voltage
VCC e Min, IOL e Max
VIL e Max, VIH e Min
DM54
0.25
0.4
DM74
0.35
0.5
IOL e 4 mA, VCC e Min
DM74
0.25
0.4
V
II
Input Current @ Max
Input Voltage
VCC e Max, VI e 7V
IIH
High Level Input Current
VCC e Max, VI e 2.7V
20
mA
IIL
Low Level Input Current
VCC e Max, VI e 0.4V
b 0.36
mA
ICC
Supply Current
VCC e Max (Note 2)
10
mA
Note 1: All typicals are at VCC e 5V, TA e 25§ C.
Note 2: ICC is measured with all outputs open, A, B, and C1 inputs at 4.5V, and C2, G1, and G2 grounded.
3
0.1
6.1
mA
’LS156 Switching Characteristics
at VCC e 5V and TA e 25§ C (See Section 1 for Test Waveforms and Output Load)
Symbol
Parameter
From (Input)
To (Output)
RL e 2 kX
CL e 15 pF
Min
Max
CL e 50 pF
Min
Units
Max
tPLH
Propagation Delay Time
Low to High Level Output
A, B, C2, G1
or G2 to Y
28
53
ns
tPHL
Propagation Delay Time
High to Low Level Output
A, B, C2, G1
or G2 to Y
33
43
ns
tPLH
Propagation Delay Time
Low to High Level Output
A or B
to Y
28
53
ns
tPHL
Propagation Delay Time
High to Low Level Output
A or B
to Y
33
43
ns
tPLH
Propagation Delay Time
Low to High Level Output
C1
to Y
28
53
ns
tPHL
Propagation Delay Time
High to Low Level Output
C1
to Y
34
43
ns
Logic Diagram
TL/F/6395 – 2
4
5
Physical Dimensions inches (millimeters)
Ceramic Leadless Chip Carrier (E)
Order Number 54LS155LMQB
NS Package Number E20A
16-Lead Ceramic Dual-In-Line Package (J)
Order Number 54LS155DMQB, 54LS156DMQB, DM54LS155J or DM54LS156J
NS Package Number J16A
6
Physical Dimensions inches (millimeters) (Continued)
16-Lead Small Outline Molded Package (M)
Order Number DM74LS155M or DM74LS156M
NS Package Number M16A
16-Lead Molded Dual-In-Line Package (N)
Order Number DM74LS155N or DM74LS156N
NS Package Number N16E
7
54LS155/DM54LS155/DM74LS155,
54LS156/DM54LS156/DM74LS156 Dual 2-Line to 4-Line Decoders/Demultiplexers
Physical Dimensions inches (millimeters) (Continued)
16-Lead Ceramic Flat Package (W)
Order Number 54LS155FMQB, 54LS156FMQB, DM54LS155W or DM54LS156W
NS Package Number W16A
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