ARINC 804 Proposed Update. ARINC 804 today Concerns Compliance Next Steps

Transcription

1 ARINC 804 Proposed Update ARINC 804 today Concerns Compliance Next Steps Presented By: Slide 1

2 A804: Taking A Step Back ARINC optical specs define geometry, spring force, materials used, why not apply to A804? Using a COTS part should have a ruggedization or qualification procedure similar to MIL 882 directive Ex. No spec for airgap in xcvr connector; moisture is a problem at in the optical path Ex. Low cost xcvrs use thermal tape, kapton, 100% tin solder/pads, weak OSA connections; Rating for vs. making work at Ind. Temp. not the same: lasers fizzle over repeated temp. swings Xcvrs are daughter cards with analog and digital systems and should be approached as such Need focus on active testing; telecom has a buffer in switch while AFDX or A818 don t Transceivers in connectors are mini-lrus Slide 2

3 Three Optical Network Building Blocks 1. Optical transceivers in network A804 equipment 2. Cabling/Passives in physical plant 3. Connectors A801 in between systems Slide 3

4 Optical Transceivers Explained Three types of lasers that vary by cost, power, and beam profile LEDs for FDDI, MM cable, wide beam, low power VCSELs, LAN, MM cable, smaller beam, high power FP/DFB lasers, WAN, SM cable, direct beam, very high power Transmitter Optical Sub Assemblies (TOSA) are lasers Receiver Optical Sub Assemblies are (ROSA) receivers A circuit board contains the logic to drive the two components A case houses the connector and shields the circuits Typical Transceiver Exploded View Single Fiber Transceivers use a BOSA Slide 4

5 Looking At An Xcvr From The Board All functions named for optics: the electrical equivalent is in reverse TDIS is Transmit disable used for safety reasons; functions if asserted; TD+/- is data; RD +/- is data; both are internally AC coupled (typically) SD is Signal Detect. When asserted data is seen at appropriate value. That time is dependent on the amplifier which varies (microseconds or less) Pin Configuration PIN # Symbol Description Logic Family MS MS Mounting studs are for mechanical attachment and are connected to chassis ground. Chassis ground is internally isolated from circuit grounds. Connection to user s ground planes is recommended. NA 1 V EER Receiver Ground (Common with Transmitter Ground) NA 2 V CCR Receiver Power Supply NA 3 SD Signal Detect. Logic 1 indicates normal operation. LV PECL or TTL 4 RD- Receiver Inverted DATA out. AC Coupled See Rx 5 RD+ Receiver Non-inverted DATA out. AC Coupled See Rx 6 V CCT Transmitter Power Supply NA 7 V EET Transmitter Ground (Common with Rx Ground) NA 8 T DIS Transmitter Disable LVTTL 9 TD+ Transmitter Non-Inverted DATA in, AC Coupled See Tx 10 TD- Transmitter Inverted DATA in. AC Coupled See Tx Slide 5

6 Copper To Fiber Electrical Design Easily terminated Proven technology Inexpensive Copper Legacy bus structure Available test equipment 3x weight of fiber Incompatible with composite skin (immunity) Connectors bus specific Fiber No EMI/RFI Lightweight Low FIRE RISK Speed/protocol independent Efficient at 1G, 10G beyond Multi-channel Expensive Hard to terminate New-New-New The change is Physical and Data Layer only The OSI 7 Layer Model Slide 6

7 Updating A804: Gaps, Suggestions Provide reference for Section 4.2 of A818 Include options for standard and high power versions. Delete references to vehicle, no system is the same Optical pad should be 3 db, like telecomm, why 2? Add 1310nm on MM fiber specifications Bi-Di: 850/xx0 (980 or 780), VCSEL as well as 31/55 or 31/49 100BASE/850nm/MMF (App B), 1000BASE/850nm/MMF (App C). Need to base on a spec: FDDI or 100BaseX? Design concerns regarding routing and telecomm connectors Reference all attenuation on fiber per meter, not KM All links need a Tx power shift as well as range (2 db) Explain Ethernet vs. Fiber Channel Spec. differences Slide 7

8 Updating Test Parameters Update ARINC specs to differentiate test methodologies for VCSEL vs LEDs Require temperature cycling with active link monitoring Define appropriate test of equipment to include not only output power or Rx Sens, but stressed link (rated aircraft link budget) with BERT or packet analysis More specification related ER vs Power should be separated. ER vs OMA is the correct debate Further discussion on how the PHY and transceiver work together as well as under a deterministic environment Industrial Temp parts or parts with digital diagnostics have processors in them; what concerns should be discussed on the processor capabilities? Slide 8

9 What s An A804 Transceiver? Operate at Ind. Temp including test showing no optical change over 100 hour period of temp cycling every hour with active test every hour looking for Tx power delta Mechanical Shock MIL-STD-883 Method 2002 Test Condition B 1500G, 0.5 sec half sine wave, 5 times/axis with pre and post test and possibly active test Vibration MIL-STD-883 Method 2007 Test Condition A. Random, multi-axis, 20G rms, sine wave sweep from Hz, 2 Hours with pre and post test and active test Thermal Shock (operation) MIL-STD-883 Method ?C to +85?C 10 cycles potentially under power to check for frost buildup Temperature Cycling (storage) MIL-STD 883 Method Test Condition A -55?C to +85?C 10 cycles, two chambers Solderability (Steam aging not required). Must follow JEDEC spec. Moisture: MIL-STD 883 Method ?C to +65/85?C at % humidity 10 cycles, units under power and monitored Accelerated Aging (HTOL) 85C, nominal voltage, 2000 Hours Temperature Cycling -40C to + 85?C, measured at 100 & 500 Cycles Low Temperature Storage -50/100?C, 2000 Hours Non-operational Damp Heat (Humidity Aging) IEC Pub Test Condition: Ca 85C / 85%RH, 1000 Hours Salt Fog: MIL-STD-810E, Method (door closed), 96 hours or MIL 5400 ARINC 801, pigtail, or methods for securing LC or SC connector joins inside the box Slide 9

10 Horror Stories Our 4G parts failed test during cycling because of frost buildup between the LC connector and transceiver lens We received transceivers from a Tier 1 vendor that had blue wires in two places on the boards and had varying lead lengths from the OSA to board Non-table driven I temp parts fail when stressed over temp cycling Non-Parylene conformal coating caused transceivers to fail after 12 hours of temp cycling and operation We ve opened LRUs and found LC cables not fully inserted into transceivers Fiber PHY chips are not all the same and this difference is made worse when paired with an AFDX chip where switch latency deviates from Ethernet performance. We ve had aircraft links differ by 2 db based on PHY chips alone. Slide 10

11 ARINC 804+: An MSA-R There are Multi-Source Agreements for SFP, XFP, SFP+ which is the direction of the telecomm industry We would like to propose a rugged pluggable Include an alternate to card edge: pluggable electrical connector Move away from BGA or gull wing Include multi-channel parts, 2 or 4 or 6 Provide guidelines for using digital diagnostics effectively Differentiate between flight critical components and on-board data communication equipment Require 100% testing with certification (AS9100) Include pigtail pull strength rating Require hermetic of laser cans Metal to metal or plastic to plastic LC to transceiver connection Slide 11

12 Next Steps Create a working group for A804 of vendors and customers with customer lead Update ARINC 803/4 with ARINC 818 and optical parameter updates Discuss technology changes in the industry regarding the elimination of LEDs in favor of VCSELs and FP lasers, the dominant optical transmission technology going forward Begin discussions of 10G networking Create a proposal for an ARINC 804 compliant transceiver Create a proposal for a modified COTS transceiver for use in ARINC applications Slide 12

13 Benefits Of Fiber To Avionics Use of composites in the airframe makes copper wire in the conduits harder to route and ground Fiber is as important as composites since it s a part of integrating that technology into airplanes It can t catch on fire: fiber can transmit data while running thru fuel tanks Much faster: 1G to 10G available today Much lighter, from 100x to 70% Slide 13

14 Contact Information Address: 749 Miner Road Highland Heights, OH Phone Fax Support: Ken Applebaum, ext 19, or Matt Krutsch, ext 21, or Commercial Off The Shelf Fiber Optic Components Modified To Work in Harsh Environments Special thanks to Luke Bolton Slide 14