Semiconductor Components Industries, LLC, 1999
December, 1999 Rev. 6
1
Publication Order Number:
SN74LS240/D
SN74LS240 SN74LS244
Octal Buffer/Line Driver
with 3-State Outputs
The SN74LS240 and SN74LS244 are Octal Buffers and Line
Drivers designed to be employed as memory address drivers, clock
drivers and bus-oriented transmitters/receivers which provide
improved PC board density.
Hysteresis at Inputs to Improve Noise Margins
3-State Outputs Drive Bus Lines or Buffer Memory Address
Registers
Input Clamp Diodes Limit High-Speed Termination Effects
GUARANTEED OPERATING RANGES
Symbol
Parameter
Min
Typ
Max
Unit
V
CC
Supply Voltage
4.75
5.0
5.25
V
T
A
Operating Ambient
Temperature Range
0
25
70
C
I
OH
Output Current High
3.0
mA
15
mA
I
OL
Output Current Low
24
mA
LOW
POWER
SCHOTTKY
Device
Package
Shipping
ORDERING INFORMATION
SN74LS240N
16 Pin DIP
1440 Units/Box
SN74LS240DW
16 Pin
SOIC
DW SUFFIX
CASE 751D
http://onsemi.com
2500/Tape & Reel
PLASTIC
N SUFFIX
CASE 738
20
1
20
1
SN74LS244N
16 Pin DIP
1440 Units/Box
SN74LS244DW
16 Pin
2500/Tape & Reel
SN74LS240 SN74LS244
http://onsemi.com
3
DC CHARACTERISTICS OVER OPERATING TEMPERATURE RANGE
(unless otherwise specified)
Limits
Symbol
Parameter
Min
Typ
Max
Unit
Test Conditions
V
IH
Input HIGH Voltage
2.0
V
Guaranteed Input HIGH Voltage for
All Inputs
V
IL
Input LOW Voltage
0.8
V
Guaranteed Input LOW Voltage for
All Inputs
V
T+
V
T
Hysteresis
0.2
0.4
V
V
CC
= MIN
V
IK
Input Clamp Diode Voltage
0.65
1.5
V
V
CC
= MIN, I
IN
= 18 mA
V
O
Output HIGH Voltage
2.4
3.4
V
V
CC
= MIN, I
OH
= 3.0 mA
V
OH
Output HIGH Voltage
2.0
V
V
CC
= MIN, I
OH
= MAX
V
O
Output LOW Voltage
0.25
0.4
V
I
OL
= 12 mA
V
CC
= V
CC
MIN,
V
IN
= V
IL
or V
IH
V
OL
Output LOW Voltage
0.35
0.5
V
I
OL
= 24 mA
V
IN
= V
IL
or V
IH
per Truth Table
I
OZH
Output Off Current HIGH
20
A
V
CC
= MAX, V
OUT
= 2.7 V
I
OZL
Output Off Current LOW
20
A
V
CC
= MAX, V
OUT
= 0.4 V
I
Input HIGH Current
20
A
V
CC
= MAX, V
IN
= 2.7 V
I
IH
Input HIGH Current
0.1
mA
V
CC
= MAX, V
IN
= 7.0 V
I
IL
Input LOW Current
0.2
mA
V
CC
= MAX, V
IN
= 0.4 V
I
OS
Output Short Circuit Current (Note 1)
40
225
mA
V
CC
= MAX
Power Supply Current
Total, Output HIGH
27
I
Total, Output LOW
LS240
44
A
V
MAX
I
CC
LS244
46
mA
V
CC
= MAX
Total at HIGH Z
LS240
50
LS244
54
Note 1: Not more than one output should be shorted at a time, nor for more than 1 second.
AC CHARACTERISTICS
(T
A
= 25
C, V
CC
= 5.0 V)
Limits
Symbol
Parameter
Min
Typ
Max
Unit
Test Conditions
t
PLH
t
PHL
Propagation Delay, Data to Output
LS240
9.0
12
14
18
ns
t
PLH
t
PHL
Propagation Delay, Data to Output
LS244
12
12
18
18
ns
C
L
= 45 pF,
R
L
= 667
t
PZH
Output Enable Time to HIGH Level
15
23
ns
t
PZL
Output Enable Time to LOW Level
20
30
ns
t
PLZ
Output Disable Time from LOW Level
15
25
ns
C
L
= 5.0 pF,
t
PHZ
Output Disable Time from HIGH Level
10
18
ns
L
R
L
= 667
SN74LS240 SN74LS244
http://onsemi.com
8
ON Semiconductor and are trademarks of Semiconductor Components Industries, LLC (SCILLC). SCILLC reserves the right to make changes
without further notice to any products herein. SCILLC makes no warranty, representation or guarantee regarding the suitability of its products for any particular
purpose, nor does SCILLC assume any liability arising out of the application or use of any product or circuit, and specifically disclaims any and all liability,
including without limitation special, consequential or incidental damages. "Typical" parameters which may be provided in SCILLC data sheets and/or
specifications can and do vary in different applications and actual performance may vary over time. All operating parameters, including "Typicals" must be
validated for each customer application by customer's technical experts. SCILLC does not convey any license under its patent rights nor the rights of others.
SCILLC products are not designed, intended, or authorized for use as components in systems intended for surgical implant into the body, or other applications
intended to support or sustain life, or for any other application in which the failure of the SCILLC product could create a situation where personal injury or
death may occur. Should Buyer purchase or use SCILLC products for any such unintended or unauthorized application, Buyer shall indemnify and hold
SCILLC and its officers, employees, subsidiaries, affiliates, and distributors harmless against all claims, costs, damages, and expenses, and reasonable
attorney fees arising out of, directly or indirectly, any claim of personal injury or death associated with such unintended or unauthorized use, even if such claim
alleges that SCILLC was negligent regarding the design or manufacture of the part. SCILLC is an Equal Opportunity/Affirmative Action Employer.
PUBLICATION ORDERING INFORMATION
ASIA/PACIFIC: LDC for ON Semiconductor Asia Support
Phone:
3036752121 (TueFri 9:00am to 1:00pm, Hong Kong Time)
Toll Free from Hong Kong 80044223781
Email: ONlitasia@hibbertco.com
JAPAN: ON Semiconductor, Japan Customer Focus Center
4321 NishiGotanda, Shinagawaku, Tokyo, Japan 1418549
Phone: 81354878345
Email: r14153@onsemi.com
Fax Response Line:
3036752167
8003443810 Toll Free USA/Canada
ON Semiconductor Website: http://onsemi.com
For additional information, please contact your local
Sales Representative.
SN74LS240/D
North America Literature Fulfillment:
Literature Distribution Center for ON Semiconductor
P.O. Box 5163, Denver, Colorado 80217 USA
Phone: 3036752175 or 8003443860 Toll Free USA/Canada
Fax: 3036752176 or 8003443867 Toll Free USA/Canada
Email: ONlit@hibbertco.com
N. American Technical Support: 8002829855 Toll Free USA/Canada
EUROPE: LDC for ON Semiconductor European Support
German Phone: (+1) 3033087140 (MF 2:30pm to 5:00pm Munich Time)
Email: ONlitgerman@hibbertco.com
French Phone: (+1) 3033087141 (MF 2:30pm to 5:00pm Toulouse Time)
Email: ONlitfrench@hibbertco.com
English Phone: (+1) 3033087142 (MF 1:30pm to 5:00pm UK Time)
Email: ONlit@hibbertco.com
PDF 
ZIP
