74ACT280
9 BIT PARITY GENERATOR/CHECKER
s
s
s
s
s
s
s
s
s
HIGH SPEED: t
PD
= 7ns (TYP.) at V
CC
= 5V
LOW POWER DISSIPATION:
I
CC
= 4µA(MAX.) at T
A
=25°C
COMPATIBLE WITH TTL OUTPUTS
V
IH
= 2V (MIN.), V
IL
= 0.8V (MAX.)
50Ω TRANSMISSION LINE DRIVING
CAPABILITY
SYMMETRICAL OUTPUT IMPEDANCE:
|I
OH
| = I
OL
= 24mA (MIN)
BALANCED PROPAGATION DELAYS:
t
PLH
≅
t
PHL
OPERATING VOLTAGE RANGE:
V
CC
(OPR) = 4.5V to 5.5V
PIN AND FUNCTION COMPATIBLE WITH
74 SERIES 280
IMPROVED LATCH-UP IMMUNITY
DIP
SOP
TSSOP
ORDER CODES
PACKAGE
DIP
SOP
TSSOP
TUBE
74ACT280B
74ACT280M
T&R
74ACT280MTR
74ACT280TTR
DESCRIPTION
The 74ACT280 is an advanced high-speed CMOS
9 BIT PARITY GENERATOR CHECKER
fabricated with sub-micron silicon gate and
double-layer metal wiring C
2
MOS tecnology.
It is composed of nine data inputs (A to I) and odd/
even parity outputs (ΣODD and
ΣEVEN).
The nine
data inputs control the output conditions. When
the number of high level input is odd,
ΣODD
output is kept high and
ΣEVEN
output low.
PIN CONNECTION AND IEC LOGIC SYMBOLS
Conservely, when the output is even,
ΣEVEN
output is kept high and
ΣODD
low.
The IC generates either odd or even parity making
it flexible application. The word-length capability is
easly expanded by cascading.
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.
April 2001
1/9
74ACT280
ABSOLUTE MAXIMUM RATINGS
Symbol
V
CC
V
I
V
O
I
IK
I
OK
I
O
Supply Voltage
DC Input Voltage
DC Output Voltage
DC Input Diode Current
DC Output Diode Current
DC Output Current
Parameter
Value
-0.5 to +7
-0.5 to V
CC
+ 0.5
-0.5 to V
CC
+ 0.5
±
20
±
20
±
50
±
200
-65 to +150
300
Unit
V
V
V
mA
mA
mA
mA
°C
°C
I
CC
or I
GND
DC V
CC
or Ground Current
Storage Temperature
T
stg
T
L
Lead Temperature (10 sec)
Absolute Maximum Ratings are those values beyond which damage to the device may occur. Functional operation under these conditions is
not implied.
RECOMMENDED OPERATING CONDITIONS
Symbol
V
CC
V
I
V
O
T
op
dt/dv
Supply Voltage
Input Voltage
Output Voltage
Operating Temperature
Input Rise and Fall Time V
CC
= 4.5 to 5.5V (note 1)
Parameter
Value
4.5 to 5.5
0 to V
CC
0 to V
CC
-55 to 125
8
Unit
V
V
V
°C
ns/V
1) V
IN
from 0.8V to 2.0V
3/9
74ACT280
DC SPECIFICATIONS
Test Condition
Symbol
Parameter
V
CC
(V)
4.5
5.5
4.5
5.5
4.5
5.5
4.5
5.5
V
OL
Low Level Output
Voltage
4.5
5.5
4.5
5.5
I
I
I
CCT
I
CC
I
OLD
I
OHD
Input Leakage Cur-
rent
Max I
CC
/Input
Quiescent Supply
Current
Dynamic Output
Current (note 1, 2)
5.5
5.5
5.5
5.5
V
O
= 0.1 V or
V
CC
-0.1V
V
O
= 0.1 V or
V
CC
-0.1V
I
O
=-50
µA
I
O
=-50
µA
I
O
=-24 mA
I
O
=-24 mA
I
O
=50
µA
I
O
=50
µA
I
O
=24 mA
I
O
=24 mA
V
I
= V
CC
or GND
V
I
= V
CC
- 2.1V
V
I
= V
CC
or GND
V
OLD
= 1.65 V max
V
OHD
= 3.85 V min
0.6
4
4.4
5.4
3.86
4.86
0.001
0.001
0.1
0.1
0.36
0.36
±
0.1
T
A
= 25°C
Min.
2.0
2.0
Typ.
1.5
1.5
1.5
1.5
4.49
5.49
0.8
0.8
4.4
5.4
3.76
4.76
0.1
0.1
0.44
0.44
±
1
1.5
40
75
-75
Max.
Value
-40 to 85°C
Min.
2.0
2.0
0.8
0.8
4.4
5.4
3.7
4.7
0.1
0.1
0.5
0.5
±
1
1.6
80
50
-50
µA
mA
µA
mA
mA
V
Max.
-55 to 125°C
Min.
2.0
2.0
0.8
0.8
V
V
Max.
Unit
V
IH
V
IL
V
OH
High Level Input
Voltage
Low Level Input
Voltage
High Level Output
Voltage
1) Maximum test duration 2ms, one output loaded at time
2) Incident wave switching is guaranteed on transmission lines with impedances as low as 50Ω
AC ELECTRICAL CHARACTERISTICS
(C
L
= 50 pF, R
L
= 500
Ω,
Input t
r
= t
f
= 3ns)
Test Condition
Symbol
Parameter
V
CC
(V)
5.0
(*)
T
A
= 25°C
Min.
3.0
Typ.
7.0
Max.
13.0
Value
-40 to 85°C
Min.
2.0
Max.
14.5
-55 to 125°C
Min.
2.0
Max.
14.5
ns
Unit
t
PLH
t
PHL
Propagation Delay
Time (Input -
ΣODD, ΣEVEN)
(*) Voltage range is 5.0V
±
0.5V
CAPACITIVE CHARACTERISTICS
Test Condition
Symbol
Parameter
V
CC
(V)
5.0
5.0
f
IN
= 10MHz
T
A
= 25°C
Min.
Typ.
4
67
Max.
Value
-40 to 85°C
Min.
Max.
-55 to 125°C
Min.
Max.
pF
pF
Unit
C
IN
C
PD
Input Capacitance
Power Dissipation
Capacitance (note
1)
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
x V
CC
x f
IN
+ I
CC
/n (per circuit)
4/9
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