National Semiconductor MM54HC244, MM74HC244 Service Manual
MM54HC244/MM74HC244
Octal TRI-STATE
Buffer
É
MM54HC244/MM74HC244 Octal TRI-STATE Buffer
January 1988
General Description
These TRI-STATE buffers utilize advanced silicon-gate
CMOS technology and are general purpose high speed noninverting buffers. They possess high drive current outputs
which enable high speed operation even when driving large
bus capacitances. These circuits achieve speeds comparable to low power Schottky devices, while retaining the advantage of CMOS circuitry, i.e., high noise immunity, and
low power consumption. All three devices have a fanout of
15 LS-TTL equivalent inputs.
The MM54HC244/MM74HC244 is a non-inverting buffer
and has two active low enables (1G and 2G). Each enable
independently controls 4 buffers. This device does not have
Schmitt trigger inputs.
All inputs are protected from damage due to static discharge by diodes to V
and ground.
CC
Connection Diagram
Dual-In-Line Package
Features
Y
Typical propagation delay: 14 ns
Y
TRI-STATE outputs for connection to system buses
Y
Wide power supply range: 2 –6V
Y
Low quiescent supply current: 80 mA (74 Series)
Y
Output current: 6 mA
Top View
Order Number MM54HC244 or MM74HC244
TL/F/5327– 1
Truth Table
’HC244
1G 1A 1Y 2G 2A 2Y
LLLLLL
LHHLHH
HLZHLZ
HHZHHZ
Hehigh level, Lelow level, Zehigh impedance
TRI-STATEÉis a registered trademark of National Semiconductor Corp.
C
1995 National Semiconductor Corporation RRD-B30M105/Printed in U. S. A.
TL/F/5327
Absolute Maximum Ratings (Notes1&2)
Operating Conditions
If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales
Office/Distributors for availability and specifications.
Supply Voltage (V
CC
)
DC Input Voltage (VIN)
DC Output Voltage (V
OUT
)
Clamp Diode Current (IIK,IOK)
DC Output Current, per pin (I
OUT
)
DC VCCor GND Current, per pin (ICC)
Storage Temperature Range (T
STG
b
b
)
b
0.5 toa7.0V
CC
CC
a
a
g
g
g
1.5 to V
0.5 to V
b
65§Ctoa150§C
1.5V
0.5V
20 mA
35 mA
70 mA
Supply Voltage (V
DC Input or Output Voltage 0 V
(V
IN,VOUT
Operating Temp. Range (T
)26V
CC
)
MM74HC
MM54HC
Input Rise or Fall Times
(t
r,tf
)V
CC
V
CC
V
CC
e
2.0V 1000 ns
e
4.5V 500 ns
e
6.0V 400 ns
Power Dissipation (PD)
(Note 3) 600 mW
S.O. Package only 500 mW
Lead Temperature (T
)
L
(Soldering 10 seconds) 260§C
DC Electrical Characteristics (Note 4)
Symbol Parameter Conditions V
CC
A
e
T
25§C
Typ Guaranteed Limits
V
Minimum High Level 2.0V 1.5 1.5 1.5 V
IH
Input Voltage 4.5V 3.15 3.15 3.15 V
6.0V 4.2 4.2 4.2 V
V
Maximum Low Level 2.0V 0.5 0.5 0.5 V
IL
Input Voltage** 4.5V 1.35 1.35 1.35 V
6.0V 1.8 1.8 1.8 V
V
Minimum High Level V
OH
Output Voltage
e
VIHor V
l
IN
I
OUT
IL
s
20 mA 2.0V 2.0 1.9 1.9 1.9 V
l
4.5V 4.5 4.4 4.4 4.4 V
6.0V 6.0 5.9 5.9 5.9 V
e
V
VIHor V
IN
I
l
OUT
I
l
OUT
l
IN
I
OUT
e
V
Maximum Low Level V
OL
Output Voltage
IL
s
6.0 mA 4.5V 4.2 3.98 3.84 3.7 V
l
s
7.8 mA 6.0V 5.7 5.48 5.34 5.2 V
l
VIHor V
IL
s
20 mA 2.0V 0 0.1 0.1 0.1 V
l
4.5V 0 0.1 0.1 0.1 V
6.0V 0 0.1 0.1 0.1 V
e
V
VIHor V
IN
I
l
OUT
I
l
OUT
I
IN
I
OZ
Maximum Input V
Current
Maximum TRI-STATE V
Output Leakage V
Current G
I
CC
Maximum Quiescent V
Supply Current I
Note 1: Absolute Maximum Ratings are those values beyond which damage to the device may occur.
Note 2: Unless otherwise specified all voltages are referenced to ground.
Note 3: Power Dissipation temperature derating Ð plastic ‘‘N’’ package:
Note 4: For a power supply of 5V
with this supply. Worst case V
) occur for CMOS at the higher voltage and so the 6.0V values should be used.
I
OZ
** V
limits are currently tested at 20% of VCC. The above VILspecification (30% of VCC) will be implemented no later than Q1, CY’89.
IL
g
and VILoccur at V
IH
e
IN
e
IN
OUT
e
e
IN
OUT
10% the worst case output voltages (VOH, and VOL) occur for HC at 4.5V. Thus the 4.5V values should be used when designing
IL
s
6.0 mA 4.5V 0.2 0.26 0.33 0.4 V
l
s
7.8 mA 6.0V 0.2 0.26 0.33 0.4 V
l
VCCor GND 6.0V
VIH,orV
IL
e
VCCor GND
V
IH
6.0V
g
0.1
g
0.5
VCCor GND 6.0V 8.0 80 160 mA
e
0 mA
b
12 mW/§C from 65§Cto85§C; ceramic ‘‘J’’ package:b12 mW/§C from 100§Cto125§C.
e
5.5V and 4.5V respectively. (The VIHvalue at 5.5V is 3.85V.) The worst case leakage current (IIN,ICC, and
CC
74HC 54HC
eb
T
40 to 85§CT
A
g
1.0
g
5
Min Max Units
)
A
b
b
40
55
A
eb
55 to 125§C
g
g
a
a
1.0 mA
10 mA
CC
85
125
V
C
§
C
§
Units
V
2
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