TECHNICAL DATA
IN74HC244A
Octal 3-State Noninverting
Buffer/Line Driver/Line Receiver
High-Performance Silicon-Gate CMOS
The IN74HC244A is identical in pinout to the LS/ALS244. The
device inputs are compatible with standard CMOS outputs; with pullup
resistors, they are compatible with LS/ALSTTL outputs.
This octal noninverting buffer/line driver/line receiver is designed
to be used with 3-state memory address drivers, clock drivers, and
other bus-oriented systems. The device has noninverting outputs and
two active-low output enables.
•
Outputs Directly Interface to CMOS, NMOS, and TTL
•
Operating Voltage Range: 2.0 to 6.0 V
•
Low Input Current: 1.0
µA
•
High Noise Immunity Characteristic of CMOS Devices
ORDERING INFORMATION
IN74HC244AN Plastic
IN74HC244ADW SOIC
T
A
= -55° to 125° C for all packages
PIN ASSIGNMENT
LOGIC DIAGRAM
FUNCTION TABLE
Inputs
Enable A,
Enable B
L
PIN 20=V
CC
PIN 10 = GND
L
H
X=don’t care
Z = high impedance
A,B
L
H
X
Outputs
YA,YB
L
H
Z
291
IN74HC244A
MAXIMUM RATINGS
*
Symbol
V
CC
V
IN
V
OUT
I
IN
I
OUT
I
CC
P
D
Tstg
T
L
*
Parameter
DC Supply Voltage (Referenced to GND)
DC Input Voltage (Referenced to GND)
DC Output Voltage (Referenced to GND)
DC Input Current, per Pin
DC Output Current, per Pin
DC Supply Current, V
CC
and GND Pins
Power Dissipation in Still Air, Plastic DIP+
SOIC Package+
Storage Temperature
Lead Temperature, 1 mm from Case for 10 Seconds
(Plastic DIP or SOIC Package)
Value
-0.5 to +7.0
-1.5 to V
CC
+1.5
-0.5 to V
CC
+0.5
±20
±35
±75
750
500
-65 to +150
260
Unit
V
V
V
mA
mA
mA
mW
°C
°C
Maximum Ratings are those values beyond which damage to the device may occur.
Functional operation should be restricted to the Recommended Operating Conditions.
+Derating - Plastic DIP: - 10 mW/°C from 65° to 125°C
SOIC Package: : - 7 mW/°C from 65° to 125°C
RECOMMENDED OPERATING CONDITIONS
Symbol
V
CC
V
IN
, V
OUT
T
A
t
r
, t
f
Parameter
DC Supply Voltage (Referenced to GND)
DC Input Voltage, Output Voltage (Referenced to GND)
Operating Temperature, All Package Types
Input Rise and Fall Time (Figure 1)
V
CC
=2.0 V
V
CC
=4.5 V
V
CC
=6.0 V
Min
2.0
0
-55
0
0
0
Max
6.0
V
CC
+125
1000
500
400
Unit
V
V
°C
ns
This device contains protection circuitry to guard against damage due to high static voltages or electric
fields. However, precautions must be taken to avoid applications of any voltage higher than maximum rated
voltages to this high-impedance circuit. For proper operation, V
IN
and V
OUT
should be constrained to the range
GND≤(V
IN
or V
OUT
)≤V
CC
.
Unused inputs must always be tied to an appropriate logic voltage level (e.g., either GND or V
CC
).
Unused outputs must be left open.
292
IN74HC244A
DC ELECTRICAL CHARACTERISTICS
(Voltages Referenced to GND)
V
CC
Symbol
Parameter
Test Conditions
V
Guaranteed Limit
25
°C
to
-55°C
1.5
3.15
4.2
0.5
1.35
1.8
1.9
4.4
5.9
3.98
5.48
0.1
0.1
0.1
0.26
0.26
±0.1
±0.5
≤85
°C
1.5
3.15
4.2
0.5
1.35
1.8
1.9
4.4
5.9
3.84
5.34
0.1
0.1
0.1
0.33
0.33
±1.0
±5.0
≤125
°C
1.5
3.15
4.2
0.5
1.35
1.8
1.9
4.4
5.9
3.7
5.2
0.1
0.1
0.1
0.4
0.4
±1.0
±10.0
µA
µA
V
Unit
V
IH
Minimum High-Level
Input Voltage
Maximum Low -
Level Input Voltage
Minimum High-Level
Output Voltage
V
OUT
= V
CC
-0.1 V
I
OUT
≤
20
µA
V
OUT
=0.1 V
I
OUT
≤
20
µA
V
IN
=V
IH
I
OUT
≤
20
µA
V
IN
=V
IH
I
OUT
≤
6.0 mA
I
OUT
≤
7.8 mA
2.0
4.5
6.0
2.0
4.5
6.0
2.0
4.5
6.0
4.5
6.0
2.0
4.5
6.0
4.5
6.0
6.0
6.0
V
V
IL
V
V
OH
V
V
OL
Maximum Low-Level
Output Voltage
V
IN
= V
IL
I
OUT
≤
20
µA
V
IN
= V
IL
I
OUT
≤
6.0 mA
I
OUT
≤
7.8 mA
I
IN
I
OZ
Maximum Input
Leakage Current
Maximum Three-
State Leakage
Current
Maximum Quiescent
Supply Current
(per Package)
V
IN
=V
CC
or GND
Output in High-Impedance
State
V
IN
= V
IL
or V
IH
V
OUT
=V
CC
or GND
V
IN
=V
CC
or GND
I
OUT
=0µA
I
CC
6.0
4.0
40
160
µA
293
IN74HC244A
AC ELECTRICAL CHARACTERISTICS
(C
L
=50pF,Input t
r
=t
f
=6.0 ns)
V
CC
Symbol
Parameter
V
Guaranteed Limit
25
°C
to
-55°C
96
18
15
110
22
19
110
22
19
60
12
10
10
15
≤85°C
≤125°C
Unit
t
PLH
, t
PHL
Maximum Propagation Delay, A to YA or B to
YB (Figures 1 and 3)
Maximum Propagation Delay , Output Enable to
YA or YB (Figures 2 and 4)
Maximum Propagation Delay , Output Enable to
YA or YB (Figures 2 and 4)
Maximum Output Transition Time, Any Output
(Figures 1 and 3)
Maximum Input Capacitance
Maximum Three-State Output Capacitance
(Output in High-Impedance State)
Power Dissipation Capacitance (Per Buffer)
2.0
4.5
6.0
2.0
4.5
6.0
2.0
4.5
6.0
2.0
4.5
6.0
-
-
115
23
20
140
28
24
140
28
24
75
15
13
10
15
135
27
23
165
33
28
165
33
28
90
18
15
10
15
ns
t
PLZ
, t
PHZ
ns
t
PZL
, t
PZH
ns
t
TLH
, t
THL
ns
C
IN
C
OUT
pF
pF
Typical @25°C,V
CC
=5.0 V
34
pF
C
PD
Used to determine the no-load dynamic power
consumption:
P
D
=C
PD
V
CC2
f+I
CC
V
CC
Figure 1. Switching Waveforms
Figure 2. Switching Waveforms
Figure 3. Test Circuit
Figure 4. Test Circuit
294
IN74HC244A
EXPANDED LOGIC DIAGRAM
(1/8 of the Device)
295
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