Datasheet DM74ALS244AWMX, DM74ALS244AWM, DM74ALS244ASJX, DM74ALS244ASJ, DM74ALS244AN Datasheet (Fairchild Semiconductor)

© 2000 Fairchild Semiconductor Corporation DS006212 www.fairchildsemi.com

September 1986
Revised February 2000

DM74ALS244A Octal 3-STATE Bus Driver

DM74ALS244A
Octal 3-STATE Bus Driver

General Description

This octal 3-STATE bus driver is designed to provide the
designer with flexibility in implementing a bus interface with
memory, microprocessor, or communication systems. This
device offers 64-extended temperature Grade product
guaranteeing perfo rmance from −40°C to +85°C. T he out­put 3-STATE gating control i s organized into two sep arate
groups of four buffers, and both control inpu ts enable the
respective outputs when s et logic LOW. The 3-STATE cir­cuitry contains a feature that maintains the buffer outputs in
3-STATE (high impedance state) during power supply
ramp-up or ramp-down. This eliminates bus glitching prob­lems that arise during power-up and power-down.

Features

■ Advanced low power oxide-isolated ion-implanted
Schottky TTL process

■ Functional and pin compatible with the 74LS counterpart

■ Improved switching per formance with less power dissi-

pation compared with the 74LS counte rpa rt

■ Switching response specified into 500Ω and 50 pF load

■ Switching response specific ations guaranteed over full

temperat ure and V

CC

supply range

■ PNP input design reduces input loading

Ordering Code:

Devices also availab le in Tape and Reel. Specify by appending th e s uffix let t er “X” to the ordering code.

Connection Diagram

Function Table

H = HIGH Level Logic State
L = LOW Level Logic State
X = Don't Care (Either LOW or HIGH Level Logic State)
Z = High Impedance (OFF) State

Logic Diagram

Order Number Package Number Package Description

DM74ALS244AWM M20B 20-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-013, 0.300 Wide
DM74ALS244ASJ M20D 20-Lead Small Outline Package (SOP), EIAJ TYPE II, 5.3mm Wide
DM74ALS244AMSA MSA20 20-Lead Shrink Small Outline Package (SSOP), EIAJ TYPE II, 5.3mm Wide
DM74ALS244AN N20A 20-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300 Wide

Input Output

G

AY

LL L
LH H

HX Z

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DM74ALS244A

Absolute Maximum Ratings(Note 1)

Note 1: The “Absolute Maximum Ratin gs” are those v alues beyon d which

the safety of the dev ice cannot be guaranteed. T he device sh ould not be
operated at these limits. The parametric values defined in the Electrical
Characteristics tables are not guaranteed at the absolute maximum ratings.
The “Recommend ed O peratin g Cond itions” t able w ill defin e the co ndition s
for actual device operation.

Recommended Operating Conditions

Electrical Characteristics

over recommended operating free air temperature (unless otherwise specified)

Switching Characteristics

over recommended operating free-air temperature range

Supply Voltage, V

CC

7V
Input Voltage 7V
Voltage Applied to Disabled Output 5.5V
Operating Free Air Temperature Range 0°C to +70°C
Storage Temperature Range −65°C to +150°C
Typical θ

JA

N Package 60.5°C/W
M Package 79.8°C/W

Symbol Parameter Min Typ Max Units

V

CC

Supply Voltage 4.5 5 5.5 V

V

IH

HIGH Level Input Voltage 2 V

V

IL

LOW Level Input Voltage 0.8 V

I

OH

HIGH Level Output Current −15 mA

I

OL

LOW Level Output Current 24 mA

T

A

Operating Free-Air Temperature 0 70 °C

Symbol Parameter Conditions Min Typ Max Units

V

IK

Input Clamp Voltage VCC = 4.5V, II = −18 mA −1.5 V

V

OH

HIGH Level VCC = 4.5V to 5.5V IOH = −0.4 mA VCC−2V
Output Voltage VCC = 4.5V IOH = −3 mA 2.4 V

IOH = Max 2 V

V

OL

LOW Level VCC = 4.5V

0.35 0.5 V

Output Voltage IOL = 24 mA

I

I

Input Current at Maximum Input Voltage VCC = 5.5V, VI = 7V 0.1 mA

I

IH

HIGH Level Input Current VCC = 5.5V, VI = 2.7V 20 µA

I

IL

LOW Level Input Current VCC = 5.5V, VIL = 0.4V −0.1 mA

I

O

Output Drive Current VCC = 5.5V, VO = 2.25V −30 −112 mA

I

OZH

HIGH Level 3-STATE Output Current VCC = 5.5V, VO = 2.7V 20 µA

I

OZL

LOW Level 3-STATE Output Current VCC = 5.5V, VO = 0.4V −20 µA

I

CC

Supply Current VCC = 5.5V

915mA

Outputs HIGH
Outputs LOW 15 24 mA
Outputs 3-STATE 17 27 mA

Symbol Parameter Conditions

From

(Input)To(Output)

Min Max Units

t

PLH

Propagation Delay Time VCC = 4.5V to 5.5V,

A Y 3 10 ns

LOW-to-HIGH Level Output CL = 50 pF,

t

PHL

Propagation Delay Time R1 = 500Ω,

A Y 3 10 ns

HIGH-to-LOW Level Output R2 = 500Ω,

t

PZH

Output Enable Time to HIGH Level Output TA = Min to Max G Y 3 20 ns

t

PZL

Output Enable Time to LOW Level Output G Y 3 20 ns

t

PHZ

Output Disable Time from HIGH Level Output G Y 2 10 ns

t

PLZ

Output Disable Time from LOW Level Output G Y 1 13 ns

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DM74ALS244A

Physical Dimensions inches (millimeters) unless otherwise noted

20-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-013, 0.300 Wide

Package Number M20B

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DM74ALS244A

Physical Dimensions inches (millimeters) unless otherwise noted (Continued)

20-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-013, 0.300 Wide

Package Number M20D

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DM74ALS244A

Physical Dimensions inches (millimeters) unless otherwise noted (Continued)

20-Lead Shrink Small Outline Package (SSOP), EIAJ TYPE II, 5.3mm Wide

Package Number MSA20

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DM74ALS244A Octal 3-STATE Bus Driver

Physical Dimensions inches (millimeters) unless otherwise noted (Continued)

20-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300 Wide

Package Number N20A

Fairchild does not assume any responsibility for use of any circuitry described, no circuit pate nt licenses are implied and
Fairchild reserves the right at any time without notice to change said circuitry and specifications.

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FAIRCHILD’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT
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SEMICONDUCTOR CORPORATION. As used herein:

1. Life support devices or systems are devices or systems

which, (a) are intended for surgical implant into the
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to perform when properly used in accordance with
instructions for use provided in the labeling, can be rea­sonably expected to result in a significant inju ry to the
user.

2. A critical component in any componen t of a life su pport
device or system whose failu re to perform can be rea­sonably expected to ca use the fa i lure of the life su pp ort
device or system, or to affect its safety or effectiveness.

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