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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
FEATURES • Word-length easily expanded by cascading • Similar pin configuration to the “180” for easy system up-grading • Generates either odd or even parity for nine data bits • Output capability: standard • 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. 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
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. 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. 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. APPLICATIONS • 25-line parity generator/checker • 81-line parity generator/checker
TYPICAL SYMBOL PARAMETER tPHL/ tPLH propagation delay In to ∑E In to ∑O CI CPD 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”. input capacitance power dissipationcapacitance per package notes 1 and 2 CONDITIONS HC CL = 15 pF; VCC = 5 V 17 20 3.5 65 18 22 3.5 65 ns ns pF pF HCT UNIT
December 1990
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Philips Semiconductors
Product specification
9-bit odd/even parity generator/checker
PIN DESCRIPTION PIN NO. 8, 9, 10, 11, 12, 13, 1, 2, 4 5, 6 7 14 SYMBOL I0 to I8 ∑E, ∑O GND VCC NAME AND FUNCTION data inputs parity outputs ground (0 V) positive supply voltage
74HC/HCT280
Fig.1 Pin configuration.
Fig.2 Logic symbol.
Fig.3 IEC logic symbol.
December 1990
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Philips Semiconductors
Product specification
9-bit odd/even parity generator/checker
74HC/HCT280
FUNCTION TABLE INPUTS number of HIGH data inputs (I0 to I8) even odd Note 1. H = HIGH voltage level L = LOW voltage level OUTPUTS ∑E H L ∑O L H
Fig.4 Functional diagram.
Fig.5 Logic diagram.
December 1990
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Philips Semiconductors
Product specification
9-bit odd/even parity generator/checker
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) 74HC SYMBOL PARAMETER min. tPHL/ tPLH propagation delay In to ∑E propagation delay In to ∑O output transition time +25 typ. 55 20 16 63 23 18 19 7 6 −40 to +85 max. min. 200 40 34 200 40 34 75 15 13 max. 250 50 43 250 50 43 95 19 16 −40 to +125 min. max. 300 60 51 300 60 51 110 22 19 ns UNIT
74HC/HCT280
TEST CONDITIONS VCC (V) 2.0 4.5 6.0 2.0 4.5 6.0 2.0 4.5 6.0 WAVEFORMS
Fig.6
tPHL/ tPLH
ns
Fig.6
tTHL/ tTLH
ns
Fig.6
December 1990
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Philips Semiconductors
Product specification
9-bit odd/even parity generator/checker
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
74HC/HCT280
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 In
UNIT LOAD COEFFICIENT 1.0
AC CHARACTERISTICS FOR 74HCT GND = 0 V; tr = tf = 6 ns; CL = 50 pF Tamb (°C) 74HCT SYMBOL PARAMETER min. tPHL/ tPLH tPHL/ tPLH tTHL/ tTLH propagation delay In to ∑E propagation delay In to ∑O output transition time +25 typ. 21 26 7 −40 to +85 max. min. 42 45 15 max. 53 56 19 −40 to +125 min. max. 63 68 22 ns ns ns 4.5 4.5 4.5 Fig.6 Fig.6 Fig.6 UNIT VCC (V) WAVEFORMS TEST CONDITIONS
December 1990
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Philips Semiconductors
Product specification
9-bit odd/even parity generator/checker
AC WAVEFORMS
74HC/HCT280
(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) t.