Fairchild DM74ALS244AMSA Octal 3-state bus driver Datasheet

Revised February 2000
DM74ALS244A
Octal 3-STATE Bus Driver
General Description
Features
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 performance from −40°C to +85°C. The output 3-STATE gating control is organized into two separate
groups of four buffers, and both control inputs enable the
respective outputs when set 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.
■ Advanced low power
Schottky TTL process
oxide-isolated
ion-implanted
■ Functional and pin compatible with the 74LS counterpart
■ Improved switching performance with less power dissipation compared with the 74LS counterpart
■ Switching response specified into 500Ω and 50 pF load
■ Switching response specifications guaranteed over full
temperature and VCC supply range
■ PNP input design reduces input loading
Ordering Code:
Order Number
Package Number
DM74ALS244AWM
M20B
DM74ALS244ASJ
M20D
DM74ALS244AMSA
DM74ALS244AN
Package Description
20-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-013, 0.300 Wide
20-Lead Small Outline Package (SOP), EIAJ TYPE II, 5.3mm Wide
MSA20
20-Lead Shrink Small Outline Package (SSOP), EIAJ TYPE II, 5.3mm Wide
N20A
20-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300 Wide
Devices also available in Tape and Reel. Specify by appending the suffix letter “X” to the ordering code.
Connection Diagram
Logic Diagram
Function Table
Input
Output
G
A
L
L
Y
L
L
H
H
H
X
Z
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
© 2000 Fairchild Semiconductor Corporation
DS006212
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DM74ALS244A Octal 3-STATE Bus Driver
September 1986
DM74ALS244A
Absolute Maximum Ratings(Note 1)
Supply Voltage, VCC
7V
Input Voltage
7V
Voltage Applied to Disabled Output
5.5V
Note 1: 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 tables are not guaranteed at the absolute maximum ratings.
The “Recommended Operating Conditions” table will define the conditions
for actual device operation.
0°C to +70°C
Operating Free Air Temperature Range
−65°C to +150°C
Storage Temperature Range
Typical θJA
N Package
60.5°C/W
M Package
79.8°C/W
Recommended Operating Conditions
Symbol
Parameter
Min
Typ
Max
4.5
5
5.5
Units
VCC
Supply Voltage
VIH
HIGH Level Input Voltage
V
VIL
LOW Level Input Voltage
0.8
V
IOH
HIGH Level Output Current
−15
mA
IOL
LOW Level Output Current
24
mA
TA
Operating Free-Air Temperature
70
°C
2
V
0
Electrical Characteristics
over recommended operating free air temperature (unless otherwise specified)
Symbol
Parameter
Conditions
Min
VIK
Input Clamp Voltage
VCC = 4.5V, II = −18 mA
VOH
HIGH Level
VCC = 4.5V to 5.5V
IOH = −0.4 mA
Output Voltage
VCC = 4.5V
IOH = −3 mA
LOW Level
VCC = 4.5V
Output Voltage
IOL = 24 mA
Max
Units
−1.5
V
VCC−2
V
2.4
V
2
V
IOH = Max
VOL
Typ
0.35
0.5
V
mA
II
Input Current at Maximum Input Voltage
VCC = 5.5V, VI = 7V
0.1
IIH
HIGH Level Input Current
VCC = 5.5V, VI = 2.7V
20
µA
IIL
LOW Level Input Current
VCC = 5.5V, VIL = 0.4V
−0.1
mA
IO
Output Drive Current
VCC = 5.5V, VO = 2.25V
−112
mA
IOZH
HIGH Level 3-STATE Output Current
VCC = 5.5V, VO = 2.7V
20
µA
IOZL
LOW Level 3-STATE Output Current
VCC = 5.5V, VO = 0.4V
−20
µA
ICC
Supply Current
VCC = 5.5V
9
15
mA
Outputs LOW
15
24
mA
Outputs 3-STATE
17
27
mA
−30
Outputs HIGH
Switching Characteristics
over recommended operating free-air temperature range
Symbol
tPLH
Parameter
Conditions
Propagation Delay Time
VCC = 4.5V to 5.5V,
LOW-to-HIGH Level Output
CL = 50 pF,
From
(Input)
To
(Output)
Min
Max
Units
A
Y
3
10
ns
A
Y
3
10
ns
Propagation Delay Time
R1 = 500Ω,
HIGH-to-LOW Level Output
R2 = 500Ω,
tPZH
Output Enable Time to HIGH Level Output
TA = Min to Max
G
Y
3
20
ns
tPZL
Output Enable Time to LOW Level Output
G
Y
3
20
ns
tPHZ
Output Disable Time from HIGH Level Output
G
Y
2
10
ns
tPLZ
Output Disable Time from LOW Level Output
G
Y
1
13
ns
tPHL
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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
3
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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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4
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
5
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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 patent 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
DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT OF FAIRCHILD
SEMICONDUCTOR CORPORATION. As used herein:
2. A critical component in any component of a life support
device or system whose failure to perform can be reasonably expected to cause the failure of the life support
device or system, or to affect its safety or effectiveness.
1. Life support devices or systems are devices or systems
which, (a) are intended for surgical implant into the
body, or (b) support or sustain life, and (c) whose failure
to perform when properly used in accordance with
instructions for use provided in the labeling, can be reasonably expected to result in a significant injury to the
user.
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