HD74LVC244A
Octal Buffers / Line Drivers with 3-state Outputs
ADE-205-110B(Z)
3rd Edition
December 1996
Description
The HD74LVC244A has eight line drivers with three state outputs in a 20 pin package. This device is a
non inverting buffer and has two active low enables (1G and 2G). Each enable independently controls four
buffers. Low voltage and high speed operation is suitable at the battery drive product (note type personal
computer) and low power consumption extends the life of a battery for long time operation.
Features
•
•
•
•
•
•
V
CC
= 2.0 V to 5.5 V
All inputs V
IH
(Max.) = 5.5 V (@V
CC
= 0 V to 5.5 V)
All outputs V
OUT
(Max.) = 5.5 V (@V
CC
= 0 V or output off state)
Typical V
OL
ground bounce < 0.8 V (@V
CC
= 3.3 V, Ta = 25°C)
Typical V
OH
undershoot > 2.0 V (@V
CC
= 3.3 V, Ta = 25°C)
High output current ±24 mA (@V
CC
= 3.0 V to 5.5 V)
Function Table
Inputs
G
H
L
L
H:
L:
X:
Z:
High level
Low level
Immaterial
High impedance
A
X
H
L
Output Y
Z
H
L
HD74LVC244A
Pin Arrangement
1G 1
1A1 2
2Y4 3
1A2 4
2Y3 5
1A3 6
2Y2 7
1A4 8
2Y1 9
GND 10
20 V
CC
19 2G
18 1Y1
17 2A4
16 1Y2
15 2A3
14 1Y3
13 2A2
12 1Y4
11 2A1
(Top view)
Absolute Maximum Ratings
Item
Supply voltage
Input diode current
Input voltage
Output diode current
Symbol
V
CC
I
IK
V
I
I
OK
Ratings
–0.5 to 6.0
–50
–0.5 to 6.0
–50
50
Output voltage
V
O
–0.5 to V
CC
+0.5
–0.5 to 6.0
Output current
V
CC
, GND current / pin
Storage temperature
I
O
I
CC
or I
GND
Tstg
±50
100
–65 to 150
Unit
V
mA
V
mA
mA
V
V
mA
mA
°C
V
O
= –0.5 V
V
O
= V
CC
+0.5 V
Output "H" or "L"
Output "Z" V
CC
:OFF
V
I
= –0.5 V
Conditions
Note: The absolute maximum ratings are values which must not individually be exceeded, and furthermore,
no two of which may be realized at the same time.
2
HD74LVC244A
Recommended Operating Conditions
Item
Supply voltage
Symbol
V
CC
Ratings
1.5 to 5.5
2.0 to 5.5
Input / output voltage
V
I
V
O
0 to 5.5
0 to V
CC
0 to 5.5
Operating temperature
Output current
Ta
I
OH
–40 to 85
–12
–24
*2
I
OL
Input rise / fall time
*1
12
24
*2
t
r
, t
f
10
Unit
V
V
V
V
V
°C
mA
mA
mA
mA
ns/V
V
CC
= 2.7 V
V
CC
= 3.0 V to 5.5 V
V
CC
= 2.7 V
V
CC
= 3.0 V to 5.5 V
Conditions
Data retention
At operation
G,
A
Output "H" or "L"
Output "Z" or V
CC
:OFF
Notes: 1. This item guarantees maximum limit when one input switches.
Waveform : Refer to test circuit of switching characteristics.
2. duty cycle
≤
50%
3
HD74LVC244A
Electrical Characteristics
Ta = –40 to 85°C
Item
Input voltage
Symbol V
CC
(V)
V
IH
Min
Max
—
Unit
V
V
V
I
OH
= –100
µA
I
OH
= –12 mA
Test Conditions
2.7 to 3.6 2.0
4.5 to 5.5 V
CC
×0.7
—
V
IL
2.7 to 3.6 —
4.5 to 5.5 —
Output voltage
V
OH
0.8
V
CC
×0.3
V
V
V
V
V
V
V
V
V
V
µA
µA
µA
µA
µA
µA
V
IN
= 5.5 V or GND
V
IN
= V
CC
, GND
V
OUT
= 5.5 V or GND
V
IN
/ V
OUT
= 5.5 V
V
IN
/ V
OUT
= 3.6 to 5.5 V
V
IN
= V
CC
or GND
V
IN
= one input at (V
CC
–0.6)V,
other inputs at V
CC
or GND
I
OL
= 100
µA
I
OL
= 12 mA
I
OL
= 24 mA
I
OH
= –24 mA
2.7 to 5.5 V
CC
–0.2 —
2.7
3.0
3.0
4.5
2.2
2.4
2.2
3.8
—
—
—
—
0.2
0.4
0.55
0.55
±5.0
±5.0
20
±10
10
500
V
OL
2.7 to 5.5 —
2.7
3.0
4.5
—
—
—
—
Input current
Off state output current
I
IN
I
OZ
I
OFF
0 to 5.5
2.7 to 5.5 —
Output leak current
0
—
Quiescent supply current I
CC
∆I
CC
2.7 to 3.6 —
2.7 to 5.5 —
3.0 to 3.6 —
4
HD74LVC244A
Switching Characteristics
Ta = –40 to 85°C
Item
Propagation delay time
Symbol V
CC
(V)
t
PLH
t
PHL
2.7
3.3±0.3
5.0±0.5
Output enable time
t
ZH
t
ZL
2.7
3.3±0.3
5.0±0.5
Output disable time
t
ZH
t
LZ
Between outut pins skew
*1
t
OSLH
t
OSHL
2.7
3.3±0.3
5.0±0.5
2.7
3.3±0.3
5.0±0.5
Input capacitance
Output capacitance
Note:
C
IN
C
O
2.7
2.7
Min
—
1.5
—
—
1.5
—
—
1.5
—
—
—
—
—
—
Typ
—
—
—
—
—
—
—
—
—
—
—
—
3.0
15.0
Max
7.5
6.5
5.0
9.0
8.0
6.5
8.0
7.0
6.0
—
1.0
1.0
—
—
Unit
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
pF
pF
G
Y
G
Y
From (Input) To (Output)
A
Y
1. This parameter is characterized but not tested.
tos
LH
= | t
PLHm
- t
PLHn
|, tos
HL
= | t
PHLm
- t
PHLn
|
5
FPGA/CPLD
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