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STMicroelectronics |
® 74AC280
9 BIT PARITY GENERATOR
s HIGH SPEED: tPD = 4 ns (TYP.) at VCC = 5V
s LOW POWER DISSIPATION:
ICC = 4 µA (MAX.) at TA = 25 oC
s HIGH NOISE IMMUNITY:
VNIH = VNIL = 28% VCC (MIN.)
s 50Ω TRANSMISSION LINE DRIVING
BM
CAPABILITY
(Plastic Package)
(Micro Package)
s SYMMETRICAL OUTPUT IMPEDANCE:
|IOH| = IOL = 24 mA (MIN)
s BALANCED PROPAGATION DELAYS:
tPLH ≅ tPHL
s OPERATING VOLTAGE RANGE:
VCC (OPR) = 2V to 6V
s PIN AND FUNCTION COMPATIBLE WITH
74 SERIES 280
ORDER CODES :
74AC280B
74AC280M
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.
Conservely, when the output is even, ΣEVEN
s IMPROVED LATCH-UP IMMUNITY
output is kept high and ΣODD low.
The IC generates either odd or even parity
DESCRIPTION
making it flexible application.
The
BIT
AC280 is
PARITY
anGaEdNvEaRncAeTdOhRigh-fsapberiecadteCdMOwSwwiwt9h.DataSheet4TcUa.hcosemcwadoirndg-.length
capability
is
easily
expanded
by
sub-micron silicon gate and double-layer metal
wiring C2MOS technology. It is ideal for low
power applications mantaining high speed
operation similar to equivalent Bipolar Schottky
TTL.
All inputs and outputs are equipped with
protection circuits against static discharge, giving
them 2KV ESD immunity and transient excess
voltage.
It is composed of nine data inputs (A to I) and
PIN CONNECTION AND IEC LOGIC SYMBOLS
December 1998
1/8
74AC280
INPUT AND OUTPUT EQUIVALENT CIRCUIT
PIN DESCRIPTION
PIN No
5, 6
8, 9, 10, 11,
12, 13, 1, 2,
4
3
7
14
S Y M B OL
ΣEVEN
ΣODD
A to I
NC
GND
VCC
NAME AND FUNCTION
Parity Outputs
Data Inputs
No Connection
Ground (0V)
Positive Supply Voltage
TRUTH TABLE
NUMBER OF INPUTS A THRU I THAT ARE HIGH
0, 2, 4, 6, 8
1, 3, 5, 7, 9
LOGIC DIAGRAM
ΣEVEN
H
L
OUTPUT
ΣODD
L
H
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