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Title, Authors, Reference, Link Abstract, Summary, Conclusions

Workshops on Spacecraft Flight Software


Presentations on spacecraft flight software from workshops.

Design of Memory Systems for Spaceborne Computers

Flight Software Workshop 2007 (FSW-07) November 5-6, 2007
Laurel, MD

   Memory devices are classified and criteria for their reliable usage are discussed.  Historical memory systems are analyzed from the 1960s through the present.  Based on these lessons, the Lunar Orbiter Laser Altimeter (LOLA) memory system was designed.  Additionally, the design of the LOLA flight software is described.

"Exploring the Planets: A Design Engineer's View and Travels"

October 8, 2006

   This talk will discuss several spacecraft and the instruments on them that either visited or are en route to Mercury, Venus, the Moon, Mars, Jupiter, Saturn, and Pluto. Along with images of these deep space bodies, there will be pictures of the spacecraft and some of the electronics which made them work. The discussion will lso show how technology has changed from the manned lunar program of the 1960s through today.
   This talk will be a look “under the hood” from the point of view of a design engineer participating in these missions. Along with the highlights and excitement, some of the challenges will be discussed.

Single Event Upset and Hardening in 0.15Ám Antifuse-Based FPGA

J.J. Wang, W. Wong, S. Wolday, B. Cronquist, J. McCollum, R. Katz, and I. Kleyner
Presented at IEEE NSREC 2003, Monterey, CA


The single event effects of a 0.15Ám antifuse-based field programmable gate array (FPGA) are investigated by heavy-ion beam test and computer simulation. Single event upsets of user flip-flop, clock, control logic, and embedded SRAM are identified and mitigation methods are proposed.

Programmed Logic Devices (PLDs) and Complex Electronic Hardware

Will Struck
FAA Transport Airplane Directorate
Transport Standards Staff


Objective is to present current policy and practices associated with the assurance of programmed logic devices (PLD), application specific integrated circuits (ASIC) and complex electronic hardware (CEH) used in aircraft applications.

Single Event Effects of a FLASH-based FPGA

J. J. Wang, Brian Cronquist, John McCollum - Actel Corporation
Rich Katz, Igor Kleyner (OSC) - NASA/GSFC
Rocky Koga - The Aerospace Corporation

Thirteenth Biennial Single Effects Symposium
Manhattan Beach, CA
April 23-25, 2002  (April 22, 2002)



  • Device and Technology
  • Architecture
  • Beam Tests and Results
  • Conclusions
    • ProASIC offers a high-density, re-programmable, and non-volatile programmable logic solution to high reliability market.
    • However, at this moment:
      • ProASIC is not suitable for space-flight application due to its SEL sensitivity at moderate LETTH.
      • But for avionics, the heavy ion and proton testing data show that it is immune to neutrons.

2003 MAPLD - Technical Program

September 9-11, 2003
Ronald Reagan Building and International Trade Center, Washington, DC

Session A: Applications: Military and Aerospace
Session B: Systems and Design Tools
Session C: Radiation and Mitigation Techniques
Session D: Processors: General Purpose and Arithmetic
Session E: Reconfigurable Computing, Evolvable Hardware, and Security
Session P: Poster Session


2002 MAPLD - Technical Program Presentations from the 2001 MAPLD International Conference are now on-line.  (September 19, 2001)
2001 MAPLD - Technical Program Presentations from the 2001 MAPLD International Conference are now on-line.  (September 19, 2001)
2000 MAPLD - Technical Program Presentations from the 2000 MAPLD International Conference are now on-line.  (May 15, 2001)
1999 MAPLD - Technical Program Presentations from the 1999 MAPLD International Conference are now on-line.
1998 MAPLD - Technical Program Presentations from the 1998 MAPLD International Conference are now on-line.
"An SEU-Hard Flip-Flop for Antifuse FPGAs"
Note that the .ppt file is much smaller and a faster download.

NSREC 2001


"Analog and Digital Single Event Effects Experiments in Space"
Note that these .ppt files are large.
"New Instrumentation, Patterns and Their Effects on TID Testing of Antifuse - Based FPGAs"
Note that the .ppt file is much smaller and a faster download.
FPGAs in Space Environment and Design Techniques
"Programmable Logic in the Space Environment and Advanced Design Techniques"
Presented June 25
th, 2001 @ NASA Goddard Space Flight Center

Short Courses

Reliable Design (MSFC)
"Advanced Design: Designing for Reliability, A Micro-Course"
Presented June 11
th, 2001 @ NASA Marshall Space Flight Center
"Fundamentals of Digital Engineering: Digital Logic, A Micro-Course"
Presented May 21st, 2001 @ NASA Goddard Space Flight Center
"Programmable Logic Devices and Architectures: A Nano-Course"
Presented March 5th, 2001 @ NASA Goddard Space Flight Center

"The Failure of a Small Satellite and the Loss of a Space Science Mission"


     On March 4, 1999, the Wide-Field Infrared Explorer (WIRE) was launched from Vandenberg Air Force Base on a Pegasus XL launch vehicle into a 540 km orbit with a planned mission duration of four months. WIRE was designed to conduct a deep infrared, extra galactic science survey 500 times more sensitive than the Infrared Astronomy Satellite (IRAS) Faint Source Catalog. The instrument consists of a cryogenically cooled, 30-centimeter telescope and all associated electronics designed to detect faint astronomical sources in two infrared wavelength bands.
     The WIRE launch was nominal. Shortly after launch, ground commands were transmitted to perform a planned secondary venting of the secondary hydrogen tank. The next pass showed that the spacecraft was tumbling at increasing rate, ultimately spinning up to 60 rpm. Within 36 hours of launch, the instrument's 4-month supply of cryogen was completely exhausted. The WIRE scientific mission was declared lost on March 8, 1999.
     The root cause of the WIRE mission loss is a digital logic design error in the instrument pyro electronics box, which inadvertently caused the cover to be ejected. The transient performance of components was not adequately considered in the box design resulting in the inadvertent pyrotechnic device firing during the initial pyro electronics box power-up. The results from the investigation into the failure mechanism will be discussed; that is, how did the mission fail.
     An equally important question is why did the mission fail. Spacecraft systems go through a variety of analyses, simulations, tests, and reviews. These will be discussed showing why the error resulted in a mishap on-orbit.
     A review of launcher and spacecraft performance and failures in the industry over the last decade will be reviewed. Trends will be presented and discussed.

"Single-Event-Transient in Clock Buffer Circuit Induced Soft Errors in Antifuse-Based FPGA" - NSREC 2000

Note: Two files.  One has the horizontally oriented charts; the other the vertically oriented ones. (Aug 1, 2000).

nsrec00_galileo_full.ppt "Analysis, Design, and Performance of Electronics In a Deep Space, High Radiation Environment" - NSREC 2000 (Aug 1, 2000)
"Recent Data on Programmable Devices and Related Technologies" - NSREC 2000
"New and Existing Microelectronics Technologies" - NEPP 2000.  Note that the .ppt file is smaller and will download faster.  (Aug 1, 2000).
"Logic Design Pathology and Space Flight Electronics" - MAPLD 1999
C0_Katz_S.ppt "FPGAs in Space Environment and Design Techniques" - MAPLD 1999
"System-on-Chip Data Processing and Handling Electronics" - MAPLD 1999
"Total Dose and SEE of Metal-To-Metal Antifuse FPGA" - MAPLD 1999
256k_eeprom_presentation.pdf 256K EEPROM Status, SMDC High Performance Microelectronics TIM, May 26, 1999.   Northrop-Grumman.
Effects_Poster_NSREC99.PDF The Effects of Architecture and Process on the Hardness of Programmable Technologies - Presented at IEEE NSREC, 1999.
Architecture and process, combined, significantly affect the hardness of programmable technologies. The effects of high energy ions, ferroelectric memory architectures, shallow trench isolation are investigated. A detailed latchup study has been performed.
SW_Poster.PDF The Impact of Software and CAE Tools on SEU in Field Programmable Gate Arrays - Presented at IEEE NSREC 1999
Field programmable gate array (FPGA) devices, heavily used in spacecraft electronics, have grown substantially in size over the past few years, causing designers to work at a higher conceptual level, with computer aided engineering (CAE) tools synthesizing and optimizing the logic from a description. It is shown that the use of commercial-off-the-shelf (COTS) CAE tools can produce unreliable circuit designs when the device is used in a radiation environment and a flip-flop is upset. At a lower level, software can be used to improve the SEU performance of a flip-flop, exploiting the configurable nature of FPGA technology and on-chip delay, parasitic resistive, and capacitive circuit elements.

A better quality version will be posted in a day or two.  rk

nsrec98_www.PDF IEEE NSREC '98 Presentation: "Current Radiation Issues for Programmable Elements and Devices."
         State of the art programmable devices are utilizing advanced processing technologies, non-standard circuit structures, and unique electrical elements in "commercial-off-the-shelf" (COTS)-based devices. The most recent technologies allow programmable devices to be used in more performance-driven applications by the spacecraft designer. This paper will show that the above factors, coupled with the systems application environment, have a strong interplay which affect the radiation hardness of programmable devices and have resultant system impacts.
          This paper will focus on three specific characteristics of COTS-based FPGAs in the radiation environment: reliability of the unprogrammed, biased antifuse for heavy ions (rupture) and the radiation-hardened, high-speed antifuse, logic upset manifesting itself as clock upset, and configuration upset. Additionally, general radiation characteristics of advanced technologies will be examined along with a discussion of future trends as commercial technology moves ahead. Testing and qualification issues concerning programmables will be discussed. Manufacturers’ modifications to their COTS-based and their impact on future programmable devices devices will be analyzed .
MPTB_COTS2_BW.pdf "STRV-1d SEE Flight Experiments : Digital Electronics and Optocouplers," Presented at the SEE Symposium, April, 1998.  This posting has the first part on the Digital Electronics and the Technologies Being Flown.  The presentation has been modified for monochrome printing. (.pdf 788 kbytes)
SEE98_BW_Final.pdf "Sub-micron FPGA/ASIC Evaluation and SEE Issues" Presented at the SEE Symposium, April, 1998.   The presentation has been modified for monochrome printing. (.pdf 1031 kbytes)
radecs97_poster.pdf "Antifuse FPGA for Space Applications," RADECS '97 (.pdf 218 kbytes)
nsrec97.pdf "Radiation Effects on Field Programmable Technologies," IEEE NSREC 1997. (.pdf 771 kbytes).
irps97onopaper.pdf "Characterization and Modeling of a Highly Reliable Metal-to-Metal Antifuse for High-Performance and High-Density Field-Programmable Gate Arrays," International Reliability Physics Symposium, 1997.
ieee94_presentation.pdf "SEU Hardening of FPGAs for Space Applications and Device Characterization," IEEE NSREC, 1994. (.pdf 1563 kbytes -) scanned).
SEU hardening techniques for FPGAs w/ circuit designs for Actel devices.  Discussion of antifuse rupture for ONO antifuses with heavy ions.  SEU, SEL, and TID characterizations for Act 1 and 2 devices.
JJ_see_sym_96.PDF Improved SEE Susceptibility of Radiation-Hardened ONO-Antifuse FPGA
Topics include: RH1280; Single Event Dielectric Rupture (SEDR); Single Event Latch-Up (SEL); Single Event Upset (SEU)     NASA/GSFC Radiation Effects Home Page

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