Philips Semiconductors

Product specification

74ALS244A/74ALS244A-1

Octal buffer (3-State)

1991 Feb 08

3

LOGIC DIAGRAM

VCC = Pin 20

Ia0

SF00230

OEa

Ia3

Ia2

Ia1

2

4

6

8

1

Ya0

Ya1

Ya2

Ya3

18

16

14

12

Ib0

Ib1

Ib2

Ib3

OEb

17

15

13

11

19

3

5

7

9

Yb0

Yb1

Yb2

Yb3

GND = Pin 10

FUNCTION TABLE

INPUTS

OUTPUTS

OEa

Ia

OEb

Ib

Ya

Yb

L

L

L

L

L

L

L

H

L

H

H

H

H

X

H

X

Z

Z

H = High voltage level

L

= Low voltage level

X = Don’t care

Z = High impedance “off” state

ABSOLUTE MAXIMUM RATINGS

(Operation beyond the limit set forth in this table may impair the useful life of the device.

Unless otherwise noted these limits are over the operating free air temperature range.)

SYMBOL

PARAMETER

RATING

UNIT

Supply voltage

–0.5 to +7.0

V

Input voltage

–0.5 to +7.0

V

Input current

–30 to +5

mA

Voltage applied to output in High output state

V

Current applied to output in Low output state

All versions

48

mA

Current applied to output in Low output state

-1 version

96

mA

Operating free-air temperature range

0 to +70

°C

Storage temperature range

–65 to +150

°C

RECOMMENDED OPERATING CONDITIONS

SYMBOL

PARAMETER

LIMITS

UNIT

SYMBOL

PARAMETER

MIN

NOM

MAX

UNIT

Supply voltage

4.5

5.0

5.5

V

High-level input voltage

2.0

V

Low-level input voltage

0.8

V

Input clamp current

–18

mA

High-level output current

–15

mA

Low level output current

All versions

24

mA

Low-level output current

-1 versions

mA

Operating free-air temperature range

0

+70

°C

NOTES: