®
74ACT280
9 BIT PARITY GENERATOR/CHECKER
s
s
s
s
s
s
s
s
s
HIGH SPEED: t
PD
= 4 ns (TYP.) at V
CC
= 5V
LOW POWER DISSIPATION:
I
CC
= 4
µA
(MAX.) at T
A
= 25
o
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
= 24 mA (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
B
M
(Plastic Package)
(Micro Package)
ORDER CODES :
74ACT280B
74ACT280M
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.
Conservely, when the output is even,
Σ
EVEN
output is kept high and
ΣODD
low.
The IC generates either odd or even parity
making it flexible application.
The word-length capability is easily 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.
DESCRIPTION
The AC280 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 technology. It is
ideal for low power applications mantaining high
speed operation similar to eqivalent Bipolar
Schottky TTL.
It is composed of nine data inputs (A to I) and
odd/even parity outputs (
Σ
ODD and
Σ
EVEN). The
PIN CONNECTION AND IEC LOGIC SYMBOLS
December 1998
1/8
74ACT280
ABSOLUTE MAXIMUM RATINGS
Symbol
V
CC
V
I
V
O
I
IK
I
OK
I
O
T
stg
T
L
Supply Voltage
DC Input Voltage
DC Output Voltage
DC Input Diode Current
DC Output Diode Current
DC Output Current
Storage Temperature
Lead Temperature (10 sec)
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
o
o
I
CC
or I
GND
DC V
CC
or Ground Current
C
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
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
-40 to +85
8
Unit
V
V
V
o
C
ns/V
1) V
IN
from 0.8 V to 2.0 V
DC SPECIFICATIONS
Symb ol
Parameter
V
CC
(V)
V
IH
V
IL
V
OH
High Level Input Voltage
Low Level Input Voltage
High Level Output
Voltage
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 Current
Max I
CC
/Input
Quiescent Supply
Current
Dynamic Output Current
(note 1, 2)
5.5
5.5
5.5
5.5
V
I (* )
=
V
IH
or
V
IL
V
O
= 0.1 V or
V
CC
- 0.1 V
V
O
= 0.1 V or
V
CC
- 0.1 V
V
I (* )
=
V
IH
or
V
IL
I
O
=-50
µA
I
O
=-50
µA
I
O
=-24 mA
I
O
=-24 mA
I
O
=50
µ
A
I
O
=50 mA
I
O
=24 mA
I
O
=24 mA
V
I
= V
CC
or GND
V
I
= V
CC
-2.1 V
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
Test Co nditions
o
Valu e
T
A
= 25 C
Min.
2.0
2.0
T yp.
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.
-40 to 85 C
Min.
2.0
2.0
0.8
0.8
Max.
o
Un it
V
V
V
V
µA
mA
µ
A
mA
mA
1) Maximum test duration 2ms, one output loaded attime
2) Incident wave switching is guaranteed on transmission lines with impedances as low as 50
Ω
.
3/8
74ACT280
AC ELECTRICAL CHARACTERISTICS
(C
L
= 50 pF, R
L
= 500
Ω,
Input t
r
= t
f
=3 ns)
Symb ol
Parameter
V
CC
(V)
t
PLH
t
PHL
Propagation Delay Time
(Input -
ΣODD, ΣEVEN)
5.0
(*)
T est Con ditio n
Valu e
T
A
= 25 C
-40 to 85
o
C
Min. T yp. Max. Min. Max.
3.0
8.5
13.0
2.0
14.5
o
Un it
ns
(*) Voltage range is 5V
±
0.5V
CAPACITIVE CHARACTERISTICS
Symb ol
Parameter
V
CC
(V)
C
IN
C
PD
Input Capacitance
Power Dissipation
Capacitance (note 1)
5.0
5.0
Test Co nditions
o
Valu e
T
A
= 25 C
Min.
T yp.
4
75
Max.
-40 to 85 C
Min.
Max.
o
Un it
pF
pF
1) C
PD
isdefined as the value of the IC’sinternal equivalent capacitance which is calculated fromthe operating current consumption without load. (Referto
Test Circuit).Average operating current can be obtained by the following equation. I
CC
(opr) = C
PD
•
V
CC
•
f
IN
+ I
CC
TEST CIRCUIT
C
L
= 50 pF or equivalent (includes jigand probe capacitance)
R
L
= R
1
= 500Ω orequivalent
R
T
= Z
OUT
of pulse generator (typically 50Ω)
4/8
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