Absolute Maximum Ratings (Note)
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
54LS
b
55
§
Cto
a
125
§
C
DM74LS 0
§
Cto
a
70
§
C
Storage Temperature Range
b
65
§
Cto
a
150
§
C
Note:
The ‘‘Absolute Maximum Ratings’’ are those values
beyond which the safety of the device cannot be guaran-
teed. 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.
Recommended Operating Conditions
Symbol Parameter
54LS244 DM74LS244
Units
Min Nom Max Min Nom Max
V
CC
Supply Voltage 4.5 5 5.5 4.75 5 5.25 V
V
IH
High Level Input Voltage 2 2 V
V
IL
Low Level Input Voltage 0.7 0.8 V
I
OH
High Level Output Current
b
12
b
15 mA
I
OL
Low Level Output Current 12 24 mA
T
A
Free Air Operating Temperature
b
55 125 0 70
§
C
Electrical Characteristics over recommended operating free air temperature range (unless otherwise noted)
Symbol Parameter Conditions Min
Typ
Max Units
(Note 1)
V
I
Input Clamp Voltage V
CC
e
Min, I
I
eb
18 mA
b
1.5 V
HYS Hysteresis (V
T
a
b
V
T
b
)V
CC
e
Min
0.2 0.4 V
Data Inputs Only
V
OH
High Level Output Voltage V
CC
e
Min, V
IH
e
Min DM74
2.7
V
IL
e
Max, I
OH
eb
1mA
V
CC
e
Min, V
IH
e
Min 54LS/DM74
2.4 3.4 V
V
IL
e
Max, I
OH
eb
3mA
V
CC
e
Min, V
IH
e
Min 54LS/DM74
2
V
IL
e
0.5V, I
OH
e
Max
V
OL
Low Level Output Voltage V
CC
e
Min I
OL
e
12 mA 54LS/DM74 0.4
V
IL
e
Max V
I
OL
e
Max DM74 0.5
V
IH
e
Min
I
OZH
Off-State Output Current, V
CC
e
Max V
O
e
2.7V
20 mA
High Level Voltage Applied V
IL
e
Max
I
OZL
Off-State Output Current,
V
IH
e
Min
V
O
e
0.4V
b
20 mA
Low Level Voltage Applied
I
I
Input Current at Maximum V
CC
e
Max V
I
e
7V (DM74)
0.1 mA
Input Voltage V
I
e
10V (54LS)
I
IH
High Level Input Current V
CC
e
Max V
I
e
2.7V 20 mA
I
IL
Low Level Input Current V
CC
e
Max V
I
e
0.4V
b
0.5
b
200 mA
I
OS
Short Circuit Output Current V
CC
e
Max (Note 2)
54LS
b
50
b
225 mA
DM74
b
40
I
CC
Supply Current V
CC
e
Max, Outputs High 13 23
Outputs Open
Outputs Low 27 46 mA
Outputs Disabled 32 54
Note 1: All typicals are at V
CC
e
5V, T
A
e
25
§
C.
Note 2: Not more than one output should be shorted at a time, and the duration should not exceed one second.
2
