1、AANALOG AND DISCRETE DATACONVERTER SYSTEMARINC CHARACTERISTIC 729-1PUBLISHED: SEPTEMBER 10, 1981AN A DOCUMENTPrepared byAIRLINES ELECTRONIC ENGINEERING COMMITTEEPublished byAERONAUTICAL RADIO, INC.2551 RIVA ROAD, ANNAPOLIS, MARYLAND 21401REPLACEMENT PAGE REVISED: April 24, 1981Copyright 1998 byAERON
2、AUTICAL RADIO, INC.2551 Riva RoadAnnapolis, Maryland 21401ARINC CHARACTERISTIC 729-1 ANALOG AND DISCRETE DATA CONVERTER SYSTEM (ADDCS)Published: September 10, 1981Prepared by the Airlines Electronic Engineering CommitteeCharacteristic 729 Adopted by the Airlines Electronic Engineering Committee: Jun
3、e 17, 1980Characteristic 729 Adopted by Industry: August 22, 1980Characteristic 729-1 Adopted by the Airlines Elect ronic Engineering Committee: March 12, 1981iiFOREWORDActivities of AERONAUTICAL RADIO, INC. (ARINC)and thePurpose of ARINC CharacteristicsAeronautical Radio, Inc. is a corporation in w
4、hich the United States scheduled airlines arethe principal stockholders. Other stockholders include a variety of other air transport companies,aircraft manufacturers and non-U.S. airlines.Activities of ARINC include the operation of an extensive system of domestic and overseasaeronautical land radio
5、 stations, the fulfillment of systems requirements to accomplish ground andairborne compatibility, the allocation and assignment of frequencies to meet those needs, thecoordination incident to standard airborne communications and electronics systems and theexchange of technical information. ARINC sp
6、onsors the Airlines Electronic EngineeringCommittee (AEEC), composed of airline technical personnel. The AEEC formulates standards forelectronic equipment and systems for the airlines. The establishment of Equipment Characteristicsis a principal function of this Committee.An ARINC Equipment Characte
7、ristic is finalized after investigation and coordination withthe airlines who have a requirement or anticipate a requirement, with other aircraft operators, withthe Military services having similar requirements, and with the equipment manufacturers. It isreleased as an ARINC Equipment Characteristic
8、 only when the interested airline companies are ingeneral agreement. Such a release does not commit any airline or ARINC to purchase equipmentso described nor does it establish or indicate recognition of the existence of an operationalrequirement for such equipment, nor does it constitute endorsemen
9、t of any manufacturers productdesigned or built to meet the Characteristic. An ARINC Characteristic has a twofold purpose,which is:(1) To indicate to the prospective manufacturers of airline electronic equipment theconsidered opinion of the airline technical people, coordinated on an industry basis,
10、concerning requisites of new equipment, and(2) To channel new equipment designs in a direction which can result in the maximumpossible standardization of those physical and electrical characteristics whichinfluence interchangeability of equipment without seriously hampering engineeringinitiative.TAB
11、LE OF CONTENTSARINC CHARACTERISTIC 729iiiITEM SUBJECT PAGE1.0 INTRODUCTION 11.1 Purpose of this Document 11.2 Summary of Operational Characteristics 11.3 Brief Description of the System 11.4 Interchangeability 11.4.1 General 11.4.2 Interchangeability Desired for the ARINC 729 ADD CS 11.4.3 “Generati
12、on Interchangeability” Considerations 11.5 Integrity and Availability 11.6 Regulatory Approval 12.0 INTERCHANGEABILITY STANDARDS 22.1 Introduction 22.2 Form Factors, Connectors and Index Pin Coding 22.2.1 Analog Data Converter (ADDCU) 22.3 Interwiring 22.4 Power Circuitry 22.4.1 Primary AC Power Inp
13、ut 22.4.2 Power Control Circuitry 22.4.3 The Common Ground 32.4.4 The AC Common Cold 32.5 System Functions and Signal Characteristics 32.6 Environmental Conditions 32.7 Cooling 32.8 Grounding and Bonding 33.0 STANDARD SIGNAL CHARACTERISTICS 43.1 Interface Standards 43.1.1 General Accuracy and Operat
14、ing Ranges 43.1.2 Resolution 43.1.3 Synchro Standards 43.1.4 Standard “Applied Voltage” 43.1.5 “Standard Ground” Signal 43.1.6 Phase Reversing Voltage Standards 43.2 Analog Data Inputs 53.2.1 Synchro Signal 53.2.2 AC Voltage Ratio 1 (ACVR 1) 53.2.3 AC Voltage Ratio 2 (ACVR 2) 53.2.4 Low Level AC (LL
15、AC) 53.2.5 High L evel AC (HLAC) 53.2.6 Low Level DC (LLDC) 53.2.7 High Level DC (HLDC) 53.2.8 DC Voltage Ratio (DCVR) 53.2.9 Potentiometer Type 1 (External Excitation) 53.2.10 Potentiometer Type 2 (1-10 K Ohms, ADDCS Excited) 53.2.11 Resistance Type 1 (90.38 Ohms, 3-Wire Input) (PROBE) 53.2.12 Resi
16、stance Type 2 (90.38 Ohms 2-Wire Input) (RESISTANCE) 53.2.13 Variable Frequency Type 1 53.2.14 Very Low Level DC (VLLDC) 63.2.15 Reluctance 63.3 Discrete Data Inputs (On-Off Signals) 63.3.1 Series Discrete 63.3.2 Shunt Discrete (Diode Isolated) 63.3.3 Ident Inputs 63.4 Reference Inputs 63.5 Referenc
17、e Outputs 63.5.1 Resistance Type 1 (PROBE) Excitation 63.5.2 Strain Gauge Excitation 63.5.3 Potentiometer Excitation 63.6 Standard Outputs 63.6.1 ARINC 429 DITS Output 63.6.2 BITE Output 6TABLE OF CONTENTSARINC CHARACTERISTIC 729ivITEM SUBJECT PAGE4.0 ANALOG AND DISCRETE DATA CONVERTER SYSTEM DESIGN
18、 74.1 System Partitioning 74.2 Hardware Functions 74.3 Firmware Functions 74.4 ADDCU Inputs 74.5 Output Data Format 74.6 Self-Test and Maintainability 84.6.1 Fault Indication 84.6.2 BITE Status Word 84.6.3 Sign Status Matrix Bits 84.7 Excitation Output Signals 85.0 PROVISIONS FOR AUTOMATIC TEST EQUI
19、PMENT 95.1 General 95.2 Unit Identification 95.2.1 Pin Allocation 95.2.2 Use of ATLAS Language 9ATTACHMENTS1-1 Typical Airborne Sub-system Block Diagrams 101-2 ADDCU Connector Placement 112 Standard Interwiring 12-22Notes Applicable to the Standard Interwiring 223 ADDCU Connector Insert Pin Layout 2
20、3-274-1 EADAC Typical Signal Processing 28-294-2 SDAC Typical Signal Processing 30-335 Input Connector Pin Assignment Standards 34-356 Guidance for Input Isolation 367 Digital Data Output Characteristics 377-1 Label Codes and SDI Code Application 37-387-2 Data Standards Summary (All data BNR) 39-407
21、-3 Discrete Word Bit/Discrete Input Correlation 40-418 Environmental Test Categories 42APPENDICES1 Chronology and Bibliography 43-45ARINC CHARACTERISTIC 729 Page 11.0 INTRODUCTION1.1 Purpose of This DocumentThis document sets forth the characteristics of anAnalog and Discrete Data Converter System (
22、ADDCS)designed for installation in commercial transportaircraft.The intent of this document is to provide general andspecific design guidance for the development andinstallation of an ADDCS primarily for airline use. Itwill describe the desired operational capability of thesystem and the standards n
23、ecessary to ensure the levelof interchangeability specified in Section 1.4.Equipment manufacturers should note that thisdocument encourages them to produce maintenance-free, high performance equipment. They are at libertyto accomplish this objective by means of designtechniques they consider to be t
24、he most appropriate, astheir airline customers are interested primarily in theend result rather than the means employed to achieveit.1.2 Summary of Operational CharacteristicsThe Analog and Discrete Data Converter Systemdescribed herein is intended to process, convert andmultiplex analog and discret
25、e signals in order toprovide them in the digital format described in ARINCSpecification 429, “Mark 33 Digital InformationTransfer System (DITS)”.The 429 output bus is expected to feed thoseequipments that use the corresponding data in order toavoid any analog to digital conversion in theseequipments
26、.1.3 Brief Description of the SystemThe Analog and Discrete Data Converter System mayconsist of one or two units (ADDCUs) designed toprocess engine data, fuel data, and aircraftconfiguration data (EADAC: Engine/Airframe DataAnalog Converter) and one or two additional unitsdesigned to process system
27、configuration data for thoseaircraft that need this function (SDAC: System DataAnalog Converter). Note that all the units are identicalin hardware terms. They are programmed differently,however, in order to fulfill EADAC and SDACfunctional needs. Attachment 1 to this documentshows typical EADAC/SDAC
28、 arrangements. Otherarrangements can be used for either function accordingto particular reliability needs.COMMENTARYThe trend among engine manufacturers toprovide engine data in digital form is expectedto reduce the level of need for analog-to-digital conversion of such data.1.4 Interchangeability1.
29、4.1 GeneralOne of the primary functions of an ARINC equipmentcharacteristic is to designate, in addition to certainperformance parameters, the interchangeability desiredfor aircraft equipment produced by variousmanufacturers. Manufacturers are referred to Section2.0 of ARINC Report 403 for the airli
30、ne industrysdefinition of Terms and General Requirements forinterchangeability. As explained in that Report, thedegree of interchangeability considered necessary andattainable for each particular equipment is specified inthe pertinent ARINC Equipment Characteristic.1.4.2 Interchangeability Desired f
31、or the ARINC 729ADDCSLimited unit interchangeability is desired for theADDCS units regardless of the manufacturing sourceof the individual items. Such interchangeability maybe achieved, in a design based on digital computers, byalteration or replacement of the program memory.If two EADACs are used o
32、n an aircraft, both shouldemploy the same program and be interchangeable. Itshould be possible to program the EADAC for use onany type of commercial aircraft regardless of thenumber of engines.If two SDACs are used on an aircraft, both shouldemploy the same program and be interchangeable. Itshould b
33、e possible to program the SDAC for use onany type of commercial aircraft.COMMENTARYThe airlines recognize that their desire for fullunit interchangeability of the EADAC andSDAC must be tempered by the fact thatsoftware differences will be needed toaccommodate the different characteristics ofthe airc
34、raft types in which they will beinstalled.1.4.3 “Generation Interchangeability” ConsiderationsThe airlines desire future evolutionary equipmentimprovements and the inclusion of any additionalfunctions in new equipments during the next few yearsto be achieved without violating the interwiring andform
35、 factor standards set forth in this document.Provisions to ensure forward-looking “generationinterchangeability” (as best can be predicted) areincluded in this document to guide manufacturers intheir future developments.1.5 Integrity and AvailabilitySince it is anticipated that this equipment may be
36、 usedto feed other aircraft systems each of which will haveits own reliability considerations, attention should bepaid to the need for integrity availability of eachADDCS unit so that the reliability of the ADDCSremains consistent with the needs of different users.1.6 Regulatory ApprovalThe equipmen
37、t should meet all applicable regulatoryrequirements. This Characteristic does not and cannotset forth the specific requirements that equipment mustmeet to be assured of approval. Such information mustbe obtained from the appropriate regulatory authority.ARINC CHARACTERISTIC 729 - Page 22.0 INTERCHAN
38、GEABILITY STANDARDS2.1 IntroductionThis section of this Characteristic sets forth the specificform factors, mounting provisions, interwiring, input andoutput interfaces and power supply characteristics desiredfor the complete Analog and Discrete Data ConverterSystem. These standards are necessary to
39、 ensure thecontinued independent design and development of boththe equipment and the airframe installation.Manufacturers should note that although thisCharacteristic does not preclude the use of different formfactors and interwiring features, the practical problem ofredesigning what will then be a s
40、tandard aircraftinstallation to accommodate some special system couldvery well make the use of that other design prohibitivelyexpensive for the customer. They should recognize,therefore, the practical advantages of developingequipment in accordance with the form factor, interwiringand signal standar
41、ds of this document.2.2 Form Factors, Connectors and Index Pin Coding2.2.1 Analog Data Converter (ADDCU)The Analog and Discrete Data Converter Unit shouldcomply with the dimensional standards in ARINCSpecification 600 “Air Transport Avionics EquipmentInterfaces (NIC Phase 1)”, for the 6 MCU form fac
42、tor. TheADDCU should also comply with ARINC 600 standardsin respect of weight, racking attachments, front and rearprojections and cooling.The ADDCU should be provided with a low insertionforce, size 3 shell ARINC 600 service connector. Thisconnector should be located on the center grid of the unitre
43、ar panel, and index pin code 04 should be used. The topand center inserts of this connector (LTP, RTP, LMP andRMP) should each provide 150 contacts. The left lowerinsert (LBP) should provide 11 single contacts and spacesfor 2 small diameter coaxial contacts. The right lowerinsert (RBP) is not used.
44、Attachment 1-2 to this documentshows the connector arrangement and Attachment 2 thepin assignments.If functions not assigned pins on the service connector inAttachment 2 of this document are needed to be brought tothe “outside world” to facilitate testing the ADDCU withautomatic test equipment (ATE)
45、, they should be assignedpins on an auxiliary connector whose type and location isselected by the equipment manufacturer. The manufacturershould observe the standards of ARINC 600 whenchoosing the location for this connector and note that,other than to accommodate the needs for equipmentidentificati
46、on by the ATE described in Section 5.2 of thisdocument, he is free to make whatever pin assignments onit he wishes. The airlines do not want the unassigned(“future spare”) pins of the service connector used forfunctions associated solely with ATE use.2.3 InterwiringThe standard interwiring for the A
47、DDCS is set forth inAttachment 2. Equipment manufacturers are cautionednot to rely on special wires, cabling or shielding for theirparticular units because they will not exist in ARINC 729aircraft installations.2.3 Interwiring (contd)NOTE: The dual-computer system architecture describedin Chapter 4
48、is based on the fact the two EDACS and thetwo SDACS (if used) are identical and interchangeable.The functions performed by each computer arecharacterized by the interwiring.COMMENTARYWhy Standardize Wiring?The standardized interwiring is the heart of anARINC Characteristic. It is this feature whicha
49、llows the airline customer to complete hisnegotiation with the airframe manufacturer so thatthe latter can proceed with engineering and initialfabrication prior to airline commitment on a specificsource of equipment. This provides the equipmentmanufacturer with many valuable months in whichto put the final “polish” on his equipment indevelopment.The readers attention is directed to the interwiringguidance in ARINC Report 414, Section 5.0. Thismaterial defines all of the basic standards utilized inairframe wiring installations, and all equipmentmanufacturers should make themselves fami
