74AC11240
OCTAL BUFFER/LINE DRIVER
WITH 3-STATE OUTPUTS
SCAS448A MAY 1987 REVISED APRIL 1996
1
POST OFFICE BOX 655303
DALLAS, TEXAS 75265
D
Flow-Through Architecture Optimizes
PCB Layout
D
Center-Pin V
CC
and GND Configurations
Minimize High-Speed Switching Noise
D
EPIC
t
(Enhanced-Performance Implanted
CMOS) 1-
m
m Process
D
500-mA Typical Latch-Up Immunity at
125
C
D
Package Options Include Plastic
Small-Outline (DW) and Shrink
Small-Outline (DB) Packages, and Standard
Plastic 300-mil DIPs (NT)
description
This octal buffer/line driver is designed specifically
to improve both the performance and density of
3-state memory address drivers, clock drivers,
and bus-oriented receivers and transmitters. This
device provides inverting outputs and
symmetrical active-low output-enable (OE)
inputs. This device features high fan-out and
improved fan-in.
The 74AC11240 is organized as two 4-bit buffers/line drivers with separate OE inputs. When OE is low, the
device passes inverted data from the A inputs to the Y outputs. When OE is high, the outputs are in the
high-impedance state.
The 74AC11240 is characterized for operation from 40
C to 85
C.
FUNCTION TABLE
(each buffer)
INPUTS
OUTPUT
OE
A
OUTPUT
Y
L
H
L
L
L
H
H
X
Z
logic symbol
This symbol is in accordance with ANSI/IEEE Std 91-1984 and IEC Publication 617-12.
2A4
2A3
2A2
2A1
2OE
1A4
1A3
1A2
1A1
1OE
2Y4
2Y3
2Y2
2Y1
1Y4
1Y3
1Y2
1Y1
12
11
10
9
4
3
2
1
14
15
16
17
13
EN
20
21
22
23
24
EN
1
1
Copyright
1996, Texas Instruments Incorporated
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of Texas Instruments
standard warranty. Production processing does not necessarily include
testing of all parameters.
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
EPIC is a trademark of Texas Instruments Incorporated.
1
2
3
4
5
6
7
8
9
10
11
12
24
23
22
21
20
19
18
17
16
15
14
13
1Y1
1Y2
1Y3
1Y4
GND
GND
GND
GND
2Y1
2Y2
2Y3
2Y4
1OE
1A1
1A2
1A3
1A4
V
CC
V
CC
2A1
2A2
2A3
2A4
2OE
DB, DW, OR NT PACKAGE
(TOP VIEW)
74AC11240
OCTAL BUFFER/LINE DRIVER
WITH 3-STATE OUTPUTS
SCAS448A MAY 1987 REVISED APRIL 1996
2
POST OFFICE BOX 655303
DALLAS, TEXAS 75265
logic diagram (positive logic)
1OE
24
1A1
1A2
1A3
1A4
23
22
21
20
1Y1
1Y2
1Y3
1Y4
1
2
3
4
2OE
13
2A1
2A2
2A3
2A4
17
16
15
14
2Y1
2Y2
2Y3
2Y4
9
10
11
12
absolute maximum ratings over operating free-air temperature range (unless otherwise noted)
Supply voltage range, V
CC
0.5 V to 6 V
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Input voltage range, V
I
(see Note 1)
0.5 V to V
CC
+ 0.5 V
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Output voltage range, V
O
(see Note 1)
0.5 V to V
CC
+ 0.5 V
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Input clamp current, I
IK
(V
I
< 0 or V
I
> V
CC
)
20 mA
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Output clamp current, I
OK
(V
O
< 0 or V
O
> V
CC
)
50 mA
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Continuous output current, I
O
(V
O
= 0 to V
CC
)
50 mA
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Continuous current through V
CC
or GND
200 mA
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Maximum power dissipation at T
A
= 55
C (in still air) (see Note 2): DB package
0.65 W
. . . . . . . . . . . . . . . . . .
DW package
1.7 W
. . . . . . . . . . . . . . . . . .
NT package
1.3 W
. . . . . . . . . . . . . . . . . . .
Storage temperature range, T
stg
65
C to 150
C
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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 maximum package power dissipation is calculated using a junction temperature of 150
_
C and a board trace length of 750 mils,
except for the NT package, which has a trace length of zero.
74AC11240
OCTAL BUFFER/LINE DRIVER
WITH 3-STATE OUTPUTS
SCAS448A MAY 1987 REVISED APRIL 1996
3
POST OFFICE BOX 655303
DALLAS, TEXAS 75265
recommended operating conditions
MIN
NOM
MAX
UNIT
VCC
Supply voltage
3
5
5.5
V
VCC = 3 V
2.1
VIH
High-level input voltage
VCC = 4.5 V
3.15
V
VCC = 5.5 V
3.85
VCC = 3 V
0.9
VIL
Low-level input voltage
VCC = 4.5 V
1.35
V
VCC = 5.5 V
1.65
VI
Input voltage
0
VCC
V
VO
Output voltage
0
VCC
V
VCC = 3 V
4
IOH
High-level output current
VCC = 4.5 V
24
mA
VCC = 5.5 V
24
VCC = 3 V
12
IOL
Low-level output current
VCC = 4.5 V
24
mA
VCC = 5.5 V
24
t
/
v
Input transition rise or fall rate
OE
0
5
ns/V
t
/
v
Input transition rise or fall rate
Data
0
10
ns/V
TA
Operating free-air temperature
40
85
C
electrical characteristics over recommended operating free-air temperature range (unless
otherwise noted)
PARAMETER
TEST CONDITIONS
VCC
TA = 25
C
MIN
MAX
UNIT
PARAMETER
TEST CONDITIONS
VCC
MIN
TYP
MAX
MIN
MAX
UNIT
3 V
2.9
2.9
IOH = 50
m
A
4.5 V
4.4
4.4
5.5 V
5.4
5.4
VOH
IOH = 4 mA
3 V
2.58
2.48
V
IOH = 24 mA
4.5 V
3.94
3.8
IOH = 24 mA
5.5 V
4.94
4.8
IOH = 75 mA
{
5.5 V
3.85
3 V
0.1
0.1
IOL = 50
m
A
4.5 V
0.1
0.1
5.5 V
0.1
0.1
VOL
IOL = 12 mA
3 V
0.36
0.44
V
IOL = 24 mA
4.5 V
0.36
0.44
IOL = 24 mA
5.5 V
0.36
0.44
IOL = 75 mA
{
5.5 V
1.65
IOZ
VO = VCC or GND
5.5 V
0.5
5
m
A
II
VI = VCC or GND
5.5 V
0.1
1
m
A
ICC
VI = VCC or GND,
IO = 0
5.5 V
8
80
m
A
Ci
VI = VCC or GND
5 V
4
pF
CO
VO = VCC or GND
5 V
10
pF
Not more than one output should be tested at a time, and the duration of the test should not exceed 10 ms.
74AC11240
OCTAL BUFFER/LINE DRIVER
WITH 3-STATE OUTPUTS
SCAS448A MAY 1987 REVISED APRIL 1996
4
POST OFFICE BOX 655303
DALLAS, TEXAS 75265
switching characteristics over recommended operating free-air temperature range,
V
CC
= 3.3 V
0.3 V (unless otherwise noted) (see Figure 1)
PARAMETER
FROM
TO
TA = 25
C
MIN
MAX
UNIT
PARAMETER
(INPUT)
(OUTPUT)
MIN
TYP
MAX
MIN
MAX
UNIT
tPLH
A
Y
1.5
7.6
10.5
1.5
11.7
ns
tPHL
A
Y
1.5
6.3
8.6
1.5
9.5
ns
tPZH
OE
Y
1.5
8.2
11.6
1.5
12.7
ns
tPZL
OE
Y
1.5
7.6
10.8
1.5
12
ns
tPHZ
OE
Y
1.5
5.5
7.5
1.5
7.8
ns
tPLZ
OE
Y
1.5
6.7
9.4
1.5
9.8
ns
switching characteristics over recommended operating free-air temperature range,
V
CC
= 5 V
0.5 V (unless otherwise noted) (see Figure 1)
PARAMETER
FROM
TO
TA = 25
C
MIN
MAX
UNIT
PARAMETER
(INPUT)
(OUTPUT)
MIN
TYP
MAX
MIN
MAX
UNIT
tPLH
A
Y
1.5
5.4
7.5
1.5
8.4
ns
tPHL
A
Y
1.5
4.6
6.6
1.5
7.2
ns
tPZH
OE
Y
1.5
5.7
8.2
1.5
9.2
ns
tPZL
OE
Y
1.5
5.3
7.7
1.5
8.7
ns
tPHZ
OE
Y
1.5
4.7
6.3
1.5
6.6
ns
tPLZ
OE
Y
1.5
5.2
7.3
1.5
7.7
ns
operating characteristics, V
CC
= 5 V, T
A
= 25
C
PARAMETER
TEST CONDITIONS
TYP
UNIT
C d
Power dissipation capacitance per buffer
Outputs enabled
CL = 50 pF
f = 1 MHz
39
pF
Cpd
Power dissipation capacitance per buffer
Outputs disabled
CL = 50 pF,
f = 1 MHz
12
pF
74AC11240
OCTAL BUFFER/LINE DRIVER
WITH 3-STATE OUTPUTS
SCAS448A MAY 1987 REVISED APRIL 1996
5
POST OFFICE BOX 655303
DALLAS, TEXAS 75265
PARAMETER MEASUREMENT INFORMATION
From Output
Under Test
CL = 50 pF
(see Note A)
LOAD CIRCUIT
S1
2
VCC
500
500
tPHL
tPLH
Output
Control
(low-level
enabling)
Output
Waveform 1
S1 at 2
VCC
(see Note B)
Output
Waveform 2
S1 at GND
(see Note B)
VOL
VOH
tPZL
tPZH
tPLZ
tPHZ
[
VCC
VCC
0 V
50% VCC
50% VCC
VOH
VOL
0 V
50% VCC
20% VCC
50% VCC
80% VCC
[
0 V
VCC
GND
Open
Input
Output
VOLTAGE WAVEFORMS
VOLTAGE WAVEFORMS
tPLH /tPHL
tPLZ /tPZL
tPHZ /tPZH
Open
2
VCC
GND
TEST
S1
NOTES: A. CL includes probe and jig capacitance.
B. Waveform 1 is for an output with internal conditions such that the output is low except when disabled by the output control.
Waveform 2 is for an output with internal conditions such that the output is high except when disabled by the output control.
C. All input pulses are supplied by generators having the following characteristics: PRR
1 MHz, ZO = 50
, tr = 3 ns, tf = 3 ns.
D. The outputs are measured one at a time with one input transition per measurement.
50% VCC
50% VCC
50% VCC
50% VCC
Figure 1. Load Circuit and Voltage Waveforms
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Copyright
1998, Texas Instruments Incorporated
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