PHILIPS 74HC280

INTEGRATED CIRCUITS
DATA SHEET
For a complete data sheet, please also download:
• The IC06 74HC/HCT/HCU/HCMOS Logic Family Specifications
• The IC06 74HC/HCT/HCU/HCMOS Logic Package Information
• The IC06 74HC/HCT/HCU/HCMOS Logic Package Outlines
74HC/HCT280
9-bit odd/even parity
generator/checker
Product specification
File under Integrated Circuits, IC06
December 1990
Philips Semiconductors
Product specification
9-bit odd/even parity generator/checker
74HC/HCT280
transmission or data retrieval systems. Both even and odd
parity outputs are available for generating or checking
even or odd parity up to 9 bits.
FEATURES
• Word-length easily expanded by cascading
• Similar pin configuration to the “180” for easy system
up-grading
The even parity output (∑E) is HIGH when an even number
of data inputs (I0 to I8) are HIGH. The odd parity output (∑0)
is HIGH when an odd number of data inputs are HIGH.
• Generates either odd or even parity for nine data bits
• Output capability: standard
Expansion to larger word sizes is accomplished by tying
the even outputs (∑E) of up to nine parallel devices to the
data inputs of the final stage. For a single-chip 16-bit
even/odd parity generator/checker, see
PC74HC/HCT7080.
• ICC category: MSI
GENERAL DESCRIPTION
The 74HC/HCT280 are high-speed Si-gate CMOS devices
and are pin compatible with low power Schottky TTL
(LSTTL). They are specified in compliance with JEDEC
standard no. 7A.
APPLICATIONS
• 25-line parity generator/checker
• 81-line parity generator/checker
The 74HC/HCT280 are 9-bit parity generators or checkers
commonly used to detect errors in high-speed data
QUICK REFERENCE DATA
GND = 0 V; Tamb = 25 °C; tr = tf = 6 ns
TYPICAL
SYMBOL PARAMETER
CONDITIONS
UNIT
HC
tPHL/ tPLH
propagation delay
HCT
CL = 15 pF; VCC = 5 V
In to ∑E
17
18
ns
In to ∑O
20
22
ns
3.5
3.5
pF
65
65
pF
CI
input capacitance
CPD
power dissipationcapacitance per package
notes 1 and 2
Notes
1. CPD is used to determine the dynamic power dissipation (PD in µW):
PD = CPD × VCC2 × fi + ∑ (CL × VCC2 × fo) where:
fi = input frequency in MHz
fo = output frequency in MHz
∑ (CL × VCC2 × fo) = sum of outputs
CL = output load capacitance in pF
VCC = supply voltage in V
2. For HC the condition is VI = GND to VCC
For HCT the condition is VI = GND to VCC − 1.5 V
ORDERING INFORMATION
See “74HC/HCT/HCU/HCMOS Logic Package Information”.
December 1990
2
Philips Semiconductors
Product specification
9-bit odd/even parity generator/checker
74HC/HCT280
PIN DESCRIPTION
PIN NO.
SYMBOL
NAME AND FUNCTION
8, 9, 10, 11, 12, 13, 1, 2, 4
I0 to I8
data inputs
5, 6
∑E, ∑O
parity outputs
7
GND
ground (0 V)
14
VCC
positive supply voltage
Fig.1 Pin configuration.
December 1990
Fig.2 Logic symbol.
3
Fig.3 IEC logic symbol.
Philips Semiconductors
Product specification
9-bit odd/even parity generator/checker
74HC/HCT280
FUNCTION TABLE
INPUTS
OUTPUTS
number of HIGH data
inputs (I0 to I8)
∑E
∑O
even
odd
H
L
L
H
Note
1. H = HIGH voltage level
L = LOW voltage level
Fig.4 Functional diagram.
Fig.5 Logic diagram.
December 1990
4
Philips Semiconductors
Product specification
9-bit odd/even parity generator/checker
74HC/HCT280
DC CHARACTERISTICS FOR 74HC
For the DC characteristics see “74HC/HCT/HCU/HCMOS Logic Family Specifications”.
Out put capability: standard
ICC category: MSI
AC CHARACTERISTICS FOR 74HC
GND = 0 V; tr = tf = 6 ns; CL = 50 pF
Tamb (°C)
TEST CONDITIONS
74HC
SYMBOL PARAMETER
+25
min.
−40 to +85
typ.
max. min.
max.
−40 to +125
min.
UNIT
VCC
(V)
WAVEFORMS
max.
tPHL/ tPLH
propagation delay
In to ∑E
55
20
16
200
40
34
250
50
43
300
60
51
ns
2.0
4.5
6.0
Fig.6
tPHL/ tPLH
propagation delay
In to ∑O
63
23
18
200
40
34
250
50
43
300
60
51
ns
2.0
4.5
6.0
Fig.6
tTHL/ tTLH
output transition time
19
7
6
75
15
13
95
19
16
110
22
19
ns
2.0
4.5
6.0
Fig.6
December 1990
5
Philips Semiconductors
Product specification
9-bit odd/even parity generator/checker
74HC/HCT280
DC CHARACTERISTICS FOR 74HCT
For the DC characteristics see “74HC/HCT/HCU/HCMOS Logic Family Specifications”.
Output capability: standard
ICC category: MSI
Note to HCT types
The value of additional quiescent supply current (∆ICC) for a unit load of 1 is given in the family specifications.
To determine ∆ICC per input, multiply this value by the unit load coefficient shown in the table below.
INPUT
UNIT LOAD COEFFICIENT
In
1.0
AC CHARACTERISTICS FOR 74HCT
GND = 0 V; tr = tf = 6 ns; CL = 50 pF
Tamb (°C)
TEST CONDITIONS
74HCT
SYMBOL PARAMETER
+25
min.
−40 to +85
typ.
max. min.
max.
−40 to +125
min.
UNIT
VCC
(V)
WAVEFORMS
max.
tPHL/ tPLH
propagation delay
In to ∑E
21
42
53
63
ns
4.5
Fig.6
tPHL/ tPLH
propagation delay
In to ∑O
26
45
56
68
ns
4.5
Fig.6
tTHL/ tTLH
output transition time
7
15
19
22
ns
4.5
Fig.6
December 1990
6
Philips Semiconductors
Product specification
9-bit odd/even parity generator/checker
74HC/HCT280
AC WAVEFORMS
(1) HC : VM = 50%; VI = GND to VCC.
HCT: VM = 1.3 V; VI = GND to 3 V.
Fig.6
Waveforms showing the data input (In) to parity outputs (∑E, ∑O) propagation delays and the output
transition time.
APPLICATION INFORMATION
For a single-chip 16-bit even/odd parity
generator/checker, see PC74HC/HCT7080.
Fig.7 Cascaded 17-bit odd/even parity generator/checker.
PACKAGE OUTLINES
See “74HC/HCT/HCU/HCMOS Logic Package Outlines”.
December 1990
7