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Supply Voltage

7V

Input Voltage

7V

Operating Free Air Temperature Range

54LS

b

DM74LS

Storage Temperature Range

b

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

54LS256

DM74LS256

Units

Min

Nom

Max

Min

Nom

Max

Supply Voltage

45

5

55

475

5

525

V

High Level Input Voltage

2

2

V

Low Level Input Voltage

07

08

V

High Level Output Current

b

04

b

04

mA

Low Level Output Current

4

8

mA

Free Air Operating Temperature

b

55

125

0

70

C

20

20

ns

00

ns

15

15

ns

00

ns

Setup Time HIGH or LOW

00

ns

E Pulse Width LOW

17

17

ns

Electrical Characteristics

Over recommended operating free air temperature range (unless otherwise noted)

Symbol

Parameter

Conditions

Min

Typ

Max

Units

(Note 1)

Input Clamp Voltage

b

15

V

High Level Output

54LS

25

V

Voltage

DM74

27

34

Low Level Output

54LS

04

Voltage

DM74

035

05

V

DM74

025

04

Input Current

Max

Inputs

01

mA

Input Voltage

E

02

High Level Input Current

Inputs

20

m

A

E

40

Low Level Input Current

Inputs

b

04

mA

E

b

08

Short Circuit

54LS

b

20

b

100

mA

Output Current

(Note 2)

DM74

b

20

b

100

Supply Current

25

mA

Note 1

Note 2

Not more than one output should be shorted at a time and the duration should not exceed one second

3