Datasheet
SN54ALS240A, SN54AS240A, SN74ALS240A, SN74AS240A
OCTAL BUFFERS/DRIVERS
WITH 3-STATE OUTPUTS
SDAS214E – DECEMBER 1982 – REVISED AUGUST 2002
4
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
recommended operating conditions
MIN NOM MAX UNIT
V
CC
Supply voltage 4.5 5 5.5 V
V
IH
High-level input voltage 2 V
V
IL
Low level in
p
ut voltage
SN54ALS240A 0.7
V
V
IL
Low
-
level
input
voltage
SN74ALS240A, ’AS240A 0.8
V
I
OH
High level out
p
ut current
SN54ALS240A, SN54AS240A –12
mA
I
OH
High
-
level
output
current
SN74ALS240A, SN74AS240A –15
mA
SN54ALS240A 12
SN74ALS240A
24
I
OL
Low-level output current
SN74ALS240A
48
†
mA
SN54AS240A 48
SN74AS240A 64
T
A
O
p
erating free-air tem
p
erature
SN54ALS240A, SN54AS240A –55 125
°
C
T
A
O erating
free
-
air
tem erature
SN74ALS240A, SN74AS240A 0 70
°C
†
Applies only to the -1 version and only if V
CC
is between 4.75 V and 5.25 V
electrical characteristics over recommended operating free-air temperature range (unless
otherwise noted)
PARAMETER
TEST CONDITIONS
SN54ALS240A SN74ALS240A
UNIT
PARAMETER
TEST
CONDITIONS
MIN TYP
‡
MAX MIN TYP
‡
MAX
UNIT
V
IK
V
CC
= 4.5 V, I
I
= –18 mA –1.2 –1.2 V
V
CC
= 4.5 V to 5.5 V, I
OH
= –0.4 mA V
CC
–2 V
CC
–2
V
OH
I
OH
= –3 mA 2.4 3.2 2.4 3.2
V
V
OH
V
CC
= 4.5 V
I
OH
= –12 mA 2
V
I
OH
= –15 mA 2
I
OL
= 12 mA 0.25 0.4 0.25 0.4
V
OL
V
CC
= 4.5 V
I
OL
= 24 mA 0.35 0.5
V
I
OL
= 48 mA
†
0.35 0.5
I
OZH
V
CC
= 5.5 V, V
O
= 2.7 V 20 20 µA
I
OZL
V
CC
= 5.5 V, V
O
= 0.4 V –20 –20 µA
I
I
V
CC
= 5.5 V, V
I
= 7 V 0.1 0.1 mA
I
IH
V
CC
= 5.5 V, V
I
= 2.7 V 20 20 µA
I
IL
V
CC
= 5.5 V, V
I
= 0.4 V –0.1 –0.1 mA
I
O
§
V
CC
= 5.5 V, V
O
= 2.25 V –20 –112 –30 –112 mA
Outputs high 4 11 4 11
I
CC
V
CC
= 5.5 V
Outputs low 13 23 13 23
mA
Outputs disabled 14 25 14 25
†
Applies only to the -1 version and only if V
CC
is between 4.75 V and 5.25 V
‡
All typical values are at V
CC
= 5 V, T
A
= 25°C.
§
The output conditions have been chosen to produce a current that closely approximates one-half of the true short-circuit output current, I
OS
.