74ACT240
OCTAL BUS BUFFER
WITH 3 STATE OUTPUTS (INVERTED)
April 1997
s
HIGH SPEED: t
PD
= 5 ns (TYP.) at V
CC
= 5V
s
LOW POWER DISSIPATION:
I
CC
= 8
A (MAX.) at T
A
= 25
o
C
s
COMPATIBLE WITH TTL OUTPUTS
V
IH
= 2V (MIN), V
IL
= 0.8V (MAX)
s
50
TRANSMISSION LINE DRIVING
CAPABILITY
s
SYMMETRICAL OUTPUT IMPEDANCE:
|I
OH
| = I
OL
= 24 mA (MIN)
s
BALANCED PROPAGATION DELAYS:
t
PLH
t
PHL
s
OPERATING VOLTAGE RANGE:
V
CC
(OPR) = 4.5V to 5.5V
s
PIN AND FUNCTION COMPATIBLE WITH
74 SERIES 240
s
IMPROVED LATCH-UP IMMUNITY
DESCRIPTION
The ACT240 is an advanced CMOS OCTAL BUS
BUFFER (3-STATE) fabricated with sub-micron
silicon gate and double-layer metal wiring C
2
MOS
technology. It is ideal for low power applications
mantaining high speed operation similar to
equivalent Bipolar Schottky TTL.
G control output governs four BUS BUFFERs.
This device is desibned to be used with 3 state
memory address drivers, etc.
The device is designed to interface directly High
Speed CMOS systems with TTL, NMOS and
CMOS output voltage levels.
All
inputs and
outputs
are
equipped with
protection circuits against static discharge, giving
them 2KV ESD immunity and transient excess
voltage.
PIN CONNECTION AND IEC LOGIC SYMBOLS
ORDER CODES :
74ACT240B
74ACT240M
M
(Micro Package)
B
(Plastic Package)
1/8
INPUT AND OUTPUT EQUIVALENT CIRCUIT
TRUTH TABLE
INPUT
OUT PUT
G
An
Yn
L
L
H
L
H
L
H
X
Z
X: "H" or "L"
Z: High impedance
PIN DESCRIPTION
PIN No
SYMBOL
NAME AND F UNCTIO N
1
1G
Output Enable Input
2, 4, 6, 8
1A1 to 1A4
Data Inputs
9, 7, 5, 3
2Y1 to 2Y4
Data Outputs
11, 13, 15, 17
2A1 to 2A4
Data Inputs
18, 16, 14, 12
1Y1 to 1Y4
Data Outputs
19
2G
Output Enabel Input
10
GND
Ground (0V)
20
V
CC
Positive Supply Voltage
ABSOLUTE MAXIMUM RATINGS
Symbol
Parameter
Val ue
Uni t
V
CC
Supply Voltage
-0.5 to +7
V
V
I
DC Input Voltage
-0.5 to V
CC
+ 0.5
V
V
O
DC Output Voltage
-0.5 to V
CC
+ 0.5
V
I
IK
DC Input Diode Current
20
mA
I
OK
DC Output Diode Current
20
mA
I
O
DC Output Current
50
mA
I
CC
or I
GND
DC V
CC
or Ground Current
400
mA
T
stg
Storage Temperature
-65 to +150
o
C
T
L
Lead Temperature (10 sec)
300
o
C
Absolute Maximum Ratings are those values beyond which damage to the device may occur. Functional operation under these condition is not implied.
RECOMMENDED OPERATING CONDITIONS
Symbol
Parameter
Valu e
Uni t
V
CC
Supply Voltage
4.5 to 5.5
V
V
I
Input Voltage
0 to V
CC
V
V
O
Output Voltage
0 to V
CC
V
T
op
Operating Temperature:
-40 to +85
o
C
dt/dv
Input Rise and Fall Time V
CC
= 4.5 to 5.5V (note 1)
8
ns/V
1) V
IN
from 0.8 V to 2.0 V
74ACT240
2/8
DC SPECIFICATIONS
Symbol
Parameter
Test Con dition s
Value
Unit
V
CC
(V)
T
A
= 25
o
C
-40 to 85
o
C
Mi n.
Typ.
Max.
Min .
Max.
V
IH
High Level Input Voltage
4.5
V
O
= 0.1 V or
V
CC
- 0.1 V
2.0
1.5
2.0
V
5.5
2.0
1.5
2.0
V
IL
Low Level Input Voltage
4.5
V
O
= 0.1 V or
V
CC
- 0.1 V
1.5
0.8
0.8
V
5.5
1.5
0.8
0.8
V
OH
High Level Output
Voltage
4.5
V
I
(*)
=
V
IH
or
V
IL
I
O
=-50
A
4.4
4.49
4.4
V
5.5
I
O
=-50
A
5.4
5.49
5.4
4.5
I
O
=-24 mA
3.86
3.76
5.5
I
O
=-24 mA
4.86
4.76
V
OL
Low Level Output
Voltage
4.5
V
I
(*)
=
V
IH
or
V
IL
I
O
=50
A
0.001
0.1
0.1
V
5.5
I
O
=50 mA
0.001
0.1
0.1
4.5
I
O
=24 mA
0.36
0.44
5.5
I
O
=24 mA
0.36
0.44
I
I
Input Leakage Current
5.5
V
I
= V
CC
or GND
0.1
1
A
I
OZ
3 State Output Leakage
Current
5.5
V
I
= V
IH
or V
IL
V
O
= V
CC
or GND
0.5
5
A
I
CCT
Max I
CC
/Input
5.5
V
I
= V
CC
-2.1 V
0.6
1.5
mA
I
CC
Quiescent Supply
Current
5.5
V
I
= V
CC
or GND
8
80
A
I
OLD
Dynamic Output Current
(note 1, 2)
5.5
V
OLD
= 1.65 V max
75
mA
I
OHD
V
OHD
= 3.85 V min
-75
mA
1) Maximum test duration 2ms, one output loaded at time
2) Incident wave switching is guaranteed on transmission lines with impedances as low as 50
.
(*) All outputs loaded.
74ACT240
3/8
CAPACITIVE CHARACTERISTICS
Symbol
Parameter
Test Con dition s
Value
Unit
V
CC
(V)
T
A
= 25
o
C
-40 to 85
o
C
Mi n.
Typ.
Max.
Min .
Max.
C
IN
Input Capacitance
5.0
4
pF
C
OUT
Output Capacitance
5.0
8
pF
C
PD
Power Dissipation
Capacitance (note 1)
5.0
21
pF
1) C
PD
is defined as the value of the IC's internal equivalent capacitance which is calculated from the operating current consumption without load. (Refer to
Test Circuit). Average operating current can be obtained by the following equation. I
CC
(opr) = C
PD
V
CC
f
IN
+ I
CC
/n (per circuit)
AC ELECTRICAL CHARACTERISTICS (C
L
= 50 pF, R
L
= 500
, Input t
r
= t
f
=3 ns)
Symbol
Parameter
T est Cond iti on
Value
Unit
V
CC
(V)
T
A
= 25
o
C
-40 to 85
o
C
Mi n.
Typ.
Max.
Min .
Max.
t
PLH
t
PHL
Propagation Delay Time
5.0
(*)
1.5
5.0
7.5
1.5
8.5
ns
t
PZL
t
PZH
Output Enable Time
5.0
(*)
1.5
6.0
8.5
1.5
9.5
ns
t
PLZ
t
PHZ
Output Disable Time
5.0
(*)
1.5
6.5
10.0
1.5
10.5
ns
(*) Voltage range is 5V
0.5V
TEST CIRCUIT
TEST
SWI TCH
t
PLH
, t
PHL
Open
t
PZL
, t
PLZ
2V
CC
t
PZH
, t
PHZ
Open
C
L
= 50 pF or equivalent (includes jig and probe capacitance)
R
L
= R
1
= 500
or equivalent
R
T
= Z
OUT
of pulse generator (typically 50
)
74ACT240
4/8
WAVEFORM 1: PROPAGATION DELAYS (f=1MHz; 50% duty cycle)
WAVEFORM 2: OUTPUT ENABLE AND DISABLE TIME (f=1MHz; 50% duty cycle)
74ACT240
5/8
DIM.
mm
inch
MIN.
TYP.
MAX.
MIN.
TYP.
MAX.
a1
0.254
0.010
B
1.39
1.65
0.055
0.065
b
0.45
0.018
b1
0.25
0.010
D
25.4
1.000
E
8.5
0.335
e
2.54
0.100
e3
22.86
0.900
F
7.1
0.280
I
3.93
0.155
L
3.3
0.130
Z
1.34
0.053
P001J
Plastic DIP20 (0.25) MECHANICAL DATA
74ACT240
6/8
SO20 MECHANICAL DATA
DIM.
mm
inch
MIN.
TYP.
MAX.
MIN.
TYP.
MAX.
A
2.65
0.104
a1
0.10
0.20
0.004
0.007
a2
2.45
0.096
b
0.35
0.49
0.013
0.019
b1
0.23
0.32
0.009
0.012
C
0.50
0.020
c1
45
(typ.)
D
12.60
13.00
0.496
0.512
E
10.00
10.65
0.393
0.419
e
1.27
0.050
e3
11.43
0.450
F
7.40
7.60
0.291
0.299
L
0.50
1.27
0.19
0.050
M
0.75
0.029
S
8
(max.)
P013L
74ACT240
7/8
Information furnished is believed to be accurate and reliable. However, SGS-THOMSON Microelectronics assumes no responsability for the
consequences of use of such information nor for any infringement of patents or other rights of third parties which may results from its use. No
license is granted by implication or otherwise under any patent or patent rights of SGS-THOMSON Microelectronics. Specifications mentioned
in this publication are subject to change without notice. This publication supersedes and replaces all information previously supplied.
SGS-THOMSON Microelectronics products are not authorized for use as critical components in life support devices or systems without express
written approval of SGS-THOMSON Microelectonics.
1997 SGS-THOMSON Microelectronics - Printed in Italy - All Rights Reserved
SGS-THOMSON Microelectronics GROUP OF COMPANIES
Australia - Brazil - Canada - China - France - Germany - Hong Kong - Italy - Japan - Korea - Malaysia - Malta - Morocco - The Netherlands -
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.
74ACT240
8/8
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