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SN54AHC240, SN74AHC240
OCTAL BUFFERS/DRIVERS
WITH 3-STATE OUTPUTS
SCLS251H
–
OCTOBER 1995
–
REVISED JULY 2003
2
POST OFFICE BOX 655303
DALLAS, TEXAS 75265
FUNCTION TABLE
(each 4-bit buffer/driver)
INPUTS
OUTPUT
Y
OE
L
A
H
L
L
L
H
H
X
Z
logic diagram (positive logic)
1
2
18
1Y1
1OE
1A1
4
16
1Y2
1A2
6
14
1Y3
1A3
8
12
1Y4
1A4
19
11
9
2Y1
2OE
2A1
13
7
2Y2
2A2
15
5
2Y3
2A3
17
3
2Y4
2A4
absolute maximum ratings over operating free-air temperature range (unless otherwise noted)
Supply voltage range, V
CC
Input voltage range, V
I
(see Note 1)
Output voltage range, V
O
(see Note 1)
Input clamp current, I
IK
(V
I
< 0)
Output clamp current, I
OK
(V
O
< 0 or V
O
> V
CC
)
Continuous output current, I
O
(V
O
= 0 to V
CC
)
Continuous current through V
CC
or GND
Package thermal impedance,
θ
JA
(see Note 2): DB package
–
0.5 V to 7 V
–
0.5 V to 7 V
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DGV package
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DW package
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
N package
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
NS package
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
PW package
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Storage temperature range, T
stg
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Stresses beyond those listed under
“
absolute maximum ratings
”
may cause permanent damage to the device. These are stress ratings only, and
functional operation of the device at these or any other conditions beyond those indicated under
“
recommended operating conditions
”
is not
implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
NOTES:
1. The input and output voltage ratings may be exceeded if the input and output current ratings are observed.
2. The package thermal impedance is calculated in accordance with JESD 51-7.
–
0.5 V to V
CC
+ 0.5 V
–
20 mA
±
20 mA
±
25 mA
±
75 mA
70
°
C/W
92
°
C/W
58
°
C/W
69
°
C/W
60
°
C/W
83
°
C/W
–
65
°
C to 150
°
C