Integral IN74LS244DW Octal 3-state noninverting buffer/line driver/line receiver Datasheet

TECHNICAL DATA
IN74LS244
Octal 3-State Noninverting Buffer/Line
Driver/Line Receiver
These octal buffers and line drivers and designed specifically to
improve both the performance and density of three-state memory
address drivers, clock drivers, and busoriented receivers and
transmitters.
This devise features high fan-out, improved fan-in, and 400 mV
noise margin.
It can be used to drive terminated lines down to 133 ohms.
• 3-State Outputs Drive Bus Lines or Buffer Memory Address
Registers
• P-N-P Inputs Reduce D-C Loading
• Hysteresis at Inputs Improves Noise Margins
ORDERING INFORMATION
IN74LS244N Plastic
IN74LS244DW SOIC
TA = 0° to 70° C
for all packages
PIN ASSIGNMENT
LOGIC DIAGRAM
FUNCTION TABLE
Inputs
PIN 20=VCC
PIN 10 = GND
Outputs
Enable A,
Enable B
A,B
YA,YB
L
L
L
L
H
H
H
X
Z
X=don’t care
Z = high impedance
1
IN74LS244
MAXIMUM RATINGS*
Symbol
Parameter
Value
Unit
VCC
Supply Voltage
7.0
V
VIN
Input Voltage
7.0
V
VOUT
Output Voltage
5.5
V
Tstg
Storage Temperature Range
-65 to +150
°C
*
Maximum Ratings are those values beyond which damage to the device may occur.
Functional operation should be restricted to the Recommended Operating Conditions.
RECOMMENDED OPERATING CONDITIONS
Symbol
Parameter
Min
Max
Unit
5.25
V
VCC
Supply Voltage
4.75
VIH
High Level Input Voltage
2.0
VIL
Low Level Input Voltage
0.8
V
IOH
High Level Output Current
-15
mA
IOL
Low Level Output Current
24
mA
TA
Ambient Temperature Range
+70
°C
0
V
DC ELECTRICAL CHARACTERISTICS over full operating conditions
Guaranteed Limit
Symbol
Parameter
Test Conditions
Min
VIK
Input Clamp Voltage
VCC = min, IIN = -18 mA
VOH
High Level Output Voltage
VCC = min, IOH = -1.0 mA
2.7
VCC = min, IOH = -3.0 mA
2.4
VCC = min, IOH = -15 mA
2.0
VOL
VT+ - VT-
Low Level Output Voltage
Max
Unit
-1.5
V
V
VCC = min, IOL = 12 mA
0.4
VCC = min, IOL = 24 mA
0.5
0.2
V
Hysteresis
VCC = min
V
IOZH
Output Off Current HIGH
VCC = max, VOUT = 2.7 V
20
µA
IOZL
Output Off Current LOW
VCC = max, VOUT = 0.4 V
-20
µA
IIH
High Level Input Current
VCC = max, VIN = 2.7 V
20
µA
VCC = max, VIN = 7.0 V
0.1
mA
-0.2
mA
-225
mA
mA
IIL
Low Level Input Current
VCC = max, VIN = 0.4 V
IO
Output Short Circuit Current
VCC = max, VO =0 V
(Note 1)
ICC
Supply
Outputs High
VCC = max
27
Current
Outputs Low
Outputs open
46
All outputs
disabled
-40
54
note 1: Not more than one output should be shorted at a time, and duration of the short-circuit should not exceed
one second
2
IN74LS244
3
IN74LS244
AC ELECTRICAL CHARACTERISTICS (TA = 25°C, VCC = 5.0 V, tr = 15 ns,
tf = 6.0 ns)
Symbol
Parameter
Test Condition
Min
Max
Unit
18
ns
18
ns
tPLH
Propagation Delay, Data to
Output
tPHL
Propagation Delay, Data to
Output
tPZH
Output Enable Time
23
ns
tPZL
Output Enable Time
30
ns
tPHZ
Output Disable Time
CL = 5 pF
18
ns
tPLZ
Output Disable Time
RL = 667 Ω
25
ns
CL = 45 pF,
RL = 667 Ω
tPZL - S1 closed, S2 opened
tPZH- S1 opened, S2 closed
tPLZ, tPHZ - S1 and S2 closed
Figure 1. Switching Waveforms
(See Figure 3)
NOTES A. CL includes probe and jig capacitance.
B. All diodes are 1N916 or 1N3064.
Figure 3. Test Circuit
4
Figure 2. Switching Waveforms
(See Figure 4)
NOTES A. CL includes probe and jig capacitance.
B. All diodes are 1N916 or 1N3064.
Figure 4. Test Circuit
IN74LS244
5
IN74LS244
EXPANDED LOGIC DIAGRAM
6
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