Conductive Coatings Protect Circuitry from EM/RF and ESD

With the trend toward smaller and smaller electronic devices, unintentional EMI/RFI interference has become more of an issue. Shielding of these interferences is critical and coatings can be successfully applied as protection on the materials used. In this paper, the different sources of interference are explored, as well as how coatings can play a critical role in protecting these sensitive components and boards.

Posted in: White Papers, Electronics & Computers, RF & Microwave Electronics

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Electric Field Quantitative Measurement System and Method

This technology could be used for medical imaging, security applications, weather prediction, and nondestructive evaluation of composites and insulators.NASA Langley Research Center’s Electric Field Imaging (EFI) system is the only noncontact method capable of quantitatively measuring the magnitude and direction of electrostatic fields in near- and far-field applications. Based on low-cost, commercially available components, the EFI system uses measurement of very-low-current, human-safe electric fields to construct a three-dimensional image of objects and people based on their dielectric properties. This platform technology, originally developed for measurement of the efficacy of electrical shielding around cables, could be optimized for a variety of applications, including medical imaging, security and detection, weather and natural disaster prediction, and nondestructive evaluation of composites and insulators. The EFI system has the potential to offer a lower-cost, portable, and safer alternative to the imaging systems currently used in these applications.

Posted in: Briefs, Electronics & Computers, Measurements, Electrical systems, Imaging and visualization, Surveillance, Weather and climate, Non-destructive tests

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Auto-Balancing Series-Stacked Input DC-DC Converter

This invention could enable practical, reliable, and efficient power conversion in high-voltage DC systems without power level limitation.ADC-DC converter that can operate from a high input voltage is needed for future high-power space applications. However, the selection of space-qualified, high-voltage transistors and filter capacitors for such a converter are very limited. The available high-voltage components have lower performance than lower-voltage components. One possible solution to this problem is connecting in series the inputs of multiple converters to lower the input voltage at the individual converter inputs. However, because of component tolerances, performance degradation, and transient events, this can result in an unbalanced voltage distribution throughout the various inputs. Excessive voltage on any of the stacked converters can damage components and cause a catastrophic failure. A circuit that could inherently balance the voltage between the inputs of multiple low-voltage DCDC converters would have better performance and reliability.

Posted in: Briefs, Board-Level Electronics, Electronics & Computers, Power Management, Capacitors, Integrated circuits, Switches, Transistors, Performance upgrades, Spacecraft

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Larger-Area Integrated Electrical Metallization Dielectric Structures with Stress-Managed Unit Cells for Extreme- Environment Semiconductor Electronics Chips

Electronic circuits that operate in high temperatures are used in automobiles, airplanes, oil drilling operations, and many other applications.The use of patterned multiple layers of thin films of metal and dielectric to form integrated circuit interconnections of transistors and/or form on-chip circuit capacitors is well known to those skilled in the art of semiconductor microelectronic fabrication. Because differing layers of thin film materials have different physical and thermal expansion properties, it is also well known that stress is inherently present in these multilayer film structures on a microelectronic chip. The amount of stress changes with temperature and as a function of lateral feature size/area across the chip. When stress anywhere within a patterned metal film feature becomes critically large (i.e., the “yield stress” is exceeded), the metal film can physically crack, buckle, or delaminate from other layers, which usually damages/fails the intended electrical operation of the microelectronic circuit.

Posted in: Briefs, Electronics & Computers, Failure modes and effects analysis, Capacitors, Integrated circuits, Fabrication, Semiconductors

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New Stamping Technique Enables Printable Electronics

The carbon nanotube stamp can print electronic inks onto rigid and flexible surfaces. (Sanha Kim and Dhanushkodi Mariappan) The next time you place your coffee order, imagine slapping onto your to-go cup a sticker that acts as an electronic decal, letting you know the precise temperature of your coffee. Engineers at MIT have invented a fast, precise printing process that may make such electronic surfaces an inexpensive reality. The stamp is made from forests of carbon nanotubes and can print electronic inks onto rigid and flexible surfaces. The stamping process should be able to print transistors small enough to control individual pixels in high-resolution displays and touchscreens. It could also offer a relatively cheap, fast way to manufacture electronic surfaces for as-yet-unknown applications.

Posted in: UpFront, Electronics

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Performance Characteristics of Digital Frequency Discriminators

Digital frequency discriminators are key components of instantaneous frequency measurement (IFM) receiver systems as well as many other complex electronic warfare (EW) systems. However, to obtain optimum results it is essential to match DFD performance levels to a specific application. DFDs are integral components of IFM receiver systems; they may also be imbedded into a wide range of military systems such as radar warning receivers (RWRs), electronic countermeasures (ECM) systems, and electronic support measures (ESM) platforms, where they help provide instantaneous frequency measurement capability.

Posted in: White Papers, White Papers, Electronics & Computers

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High-Speed Switched Serial Fabrics Improve System Design

Well into its third decade of widespread deployment, VME adopted the new VXS gigabit serial interface, clearly representing the most significant leap in backplane data transfer rates throughout its entire history. Because VXS delivered such a dramatic improvement in embedded system performance, the use of gigabit serial technology was extended to create VPX. The OpenVPX initiative followed shortly thereafter, as risk-averse government agencies mandated the need for industry-wide standards. The hallmark of any successful standard is that it continues to evolve with technology, and none offers a better example than VME’s evolution to VXS and VPX.

Posted in: White Papers, White Papers, Electronics & Computers

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High-Speed Real Time Recording Systems

In today’s world of high-speed A/D converters operating in the gigahertz range, real-time signal recording has become a challenging task that requires specialized hardware and intelligent application software. When designing a real-time recorder capable of streaming sustained data to disk at rates of up to 5 GB/sec and higher, the system developer has to consider the limitations presented by the recorder’s operating and file systems, the limitations of disk drive technology, the hardware interfaces, and the RAID controller technology.

Posted in: White Papers, White Papers, Electronics & Computers

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Putting FPGAs to Work in Software Radio Systems

FPGAs have become an increasingly important resource for software radio systems. Programmable logic technology now offers significant advantages for implementing software radio functions such as DDCs (Digital Downconverters). Over the past few years, the functions associated with DDCs have seen a shift from being delivered in ASICs (Application-Specific ICs) to operating as IP (Intellectual Property) in FPGAs.

Posted in: White Papers, White Papers, Electronics & Computers, Semiconductors & ICs

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Critical Techniques for High-Speed A/Ds In Real-Time Systems Handbook

To help define the meaning of “high-speed A/D” used in this handbook, we will be focusing primarily on A/D converters with sampling rates higher than 100 MHz. We will review sampling techniques, FPGA technology and we will present the latest Pentek high-speed A/D products and applications based on them.

Posted in: White Papers, White Papers, Electronics & Computers

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