EDN articles from September 2007

EDN archives from September 2007

Outputs don't swing rail to rail.
September 3, 2007... by Bonnie Baker Single-supply amplifiers do not truly swing rail to rail at the output. Near the rail, the amplifier is nonlinear. For linear operation, the output of single-supply amplifiers can come within only 50 to 300 mV of each rail...

TDR: taking the pulse of signal integrity.
September 3, 2007... by Paul Rako, Technical Editor Time-domain reflectometry will help you design and troubleshoot cables, connectors, fast PCB traces, and high-speed packages. With TDR instruments, you can ensure the signal integrity of fast digital signals...

The 802.11n standard: grown up at last.
September 3, 2007... by Ann R Thryft Contributing Technical Editor The 802.11n Wi-Fi standard promises much. After an especially angst-ridden development process, it's ready to go to work. Even for a wireless-communications standard, the 802.11n...

Nonvolatile digital potentiometer gates logic signal.
September 3, 2007... Reinhardt Wagner, Maxim Integrated Products, Ottobrunn, Germany Edited by Charles H Small and Fran Granville This Design Idea describes a simple alternative to a nonvolatile gating function you typically implement using PAL...

Soft-limiter circuit forms basis of simple AM modulator.
September 3, 2007... Herminio Martínez, Encarna García, and Juan Gámiz, Technical University of Catalonia, Barcelona, Spain Edited by Charles H Small and Fran Granville One of the most popular circuits for amplitude control in...

Circuits monitor and balance large lithium-ion batteries.
September 3, 2007... Daniel Gomez-Ibanez, Woods Hole Oceanographic Institution, Woods Hole, MA Edited by Charles H Small and Fran Granville When using rechargeable lithium-ion cells in large batteries, such as those in an electric vehicle, you encounter...

White-LED driver operates down to 1.2V supply voltage.
September 3, 2007... Dave Wuchinich, Modal Mechanics, Yonkers, NY Edited by Charles H Small and Fran Granville Many LED drivers, using both charge pumps and inductors, are available to boost the 1.2 to 2.4V available from single- and dual-cell NiMH...

Immaturity in 802.11n products guides a return to a wired LAN.
September 3, 2007... by Maury Wright, Editorial Director I recently bought a Draft-n-compliant wireless router but was extremely disappointed in the performance. The event revamped my thinking about the 'IT' infrastructure in my home. And it made me wonder how...

Apple's iPhone delivers more than just a dial tone.
September 3, 2007... by Brian Dipert, Senior Technical Editor By now, you're probably overwhelmed with hands-on analyses of the iPhone, which Apple and partner AT&T began selling on June 29. Few reviewers, though, have cracked open the device's case and peered...

TDR and S-parameter measurements: How much performance do you need?
September 3, 2007... by Dima Smolyansky, Tektronix Inc Time-domain techniques are challenging established frequency-domain measurements in the analysis of high-speed serial networks. To obtain meaningful results, the measurement equipment must have adequate...

FPGA-based design yields low-cost arbitrary-frequency generator.
September 3, 2007... by Eugene Palatnik, ITEC Engineering An FPGA-based design is perfect for producing an arbitrary-frequency generator with broad applications in biomedical devices and anywhere else that you need signals of highly accurate, precisely known...

Audio, video chips enhance handheld devices' features, shrink power needs.
September 3, 2007... by Margery Conner A handheld consumer device's display and audio are often the features that determine the product's success or failure. However, audio and video bells and whistles can also destroy a battery-operated device's power budget....

LabView V8.5 adds state charts, enhances multithreaded-application performance in multicore microprocessors, FPGAs.
September 3, 2007... by Dan Strassberg Amid the traditional annual fanfare of NIWeek in its home city of Austin, TX, National Instruments has announced Version 8.5 of LabView, the company's graphical system-design-software platform for test-, control-, and...

Software simplifies use of AWGs for digital-RF testing.
September 3, 2007... by Dan Strassberg Tektronix has announced RFXpress, a software package for creating and editing digitally modulated RF (radio-frequency)-, IF (intermediate-frequency)-, and IQ (in-phase/quadrature)-signal waveforms, which the company's...

CESI partners with Tektronix to establish research lab.
September 3, 2007... by Fran Granville Tektronix Inc has announced a partnership with the CESI (China Electronics Standardization Institution) to set up a joint lab for advanced research and assessment of digital-RF and DTV (digital-TV) standards in China. The...

Waveform filtering shapes motor-drive currents.(Brief article)
September 3, 2007... by Graham Prophet Epcos designed its SineFormer filter technology to improve the output waveforms from high-power frequency converters and motor drives. The unit simultaneously converts phase-to-phase voltages into a sinusoidal signal,...

Low-power dc/dc downconverters target portable designs.
September 3, 2007... by Graham Prophet Texas Instruments designed its TPS622xx series of 2.25-MHz-switching-frequency dc/dc step-down converters to power microcontrollers and DSPs in portable electronics. In three versions, the TPS62290, TPS62260, and TPS62240...

DragonFire reference design gets BSP.(Brief article)
September 3, 2007... by Graham Prophet EBV Elektronik and Domologic have announced a BSP (board-support package) for the Freescale (www.freescale.com )-microprocessor-based DragonFire reference design. The companies based this package on JControl technology;...

IBM's Jeffrey Taft: bringing intelligence to the power grid.
September 3, 2007... By Margery Conner Jeffrey Taft is chief intelligent-grid architect for IBM's Global Business Services. As such, his background in digital-signal processing is vital as he heads up IBM's effort to become the purveyor of the software that...

Scope.
September 3, 2007... Edited by Ron Wilson Looking Ahead To the ARM developers' conference The annual event for users of the ARM microprocessor architecture kicks off Oct 2 in Santa Clara, CA, and just looking at the subjects of the technical tracks...

How low can you go? A look at 45-nm-IC-design challenges.
September 13, 2007... by Michael Santarini, Senior Editor If you have tools for the 65-nm or even the 90-nm node, moving to the 45-nm node requires no retooling. but designers moving to this node must adopt some advanced design techniques and be aware of some...

Permanent-magnet motors boost efficiency and power density.
September 13, 2007... by Margery Conner, Technical Editor Sensorless versions of these highly efficient motors reduce cost and parts count, but the motors still require complex control algorithms. Match the right motor type and controller to your application...

CPLD's internal oscillator performs autocalibration.
September 13, 2007... Rafael Camarota, Altera Corp, San Jose, CA Edited By Charles H Small and Fran Granville The MAX II CPLD family from Altera (www.altera.com ) features an internal oscillator that dissipates much lower power than do external oscillators....

Swapping bits improves performance of FPGA-PWM counter.
September 13, 2007... Stefaan Vanheesbeke, Ledegem, Belgium Edited By Charles H Small and Fran Granville When you need some analog outputs and you have an FPGA in your system, you probably choose to use a PWM module and a simple lowpass filter such as those...

Relays eliminate high-voltage noise.
September 13, 2007... Jui-I Tsai, Woei-Wu Pai, Feng-Chang Hsu, Po-Jui Chen, Ching-Cheng Teng, and Tai-Shan Liao, National Applied Research Laboratories, Hsinchu, Taiwan Edited By Charles H Small and Fran Granville Most laboratories and industrial...

VHDL program enables PCI-bus-arbiter core.(VHSIC hardware description language)
September 13, 2007... Antonio Di Rocco, Selex Communications, Chieti, Italy Edited By Charles H Small and Fran Granville This Design Idea describes a VHDL implementation of a PCI 2.2-bus arbiter (Figure 1 ). Any PCI system may have one or more PCI-master...

PCB prototypes add value in the design process.
September 13, 2007... by Maury Wright, Editorial Director I spend a good portion of my time meeting with companies in the EOEM (electronics-original-equipment-manufacturing) market, and most of those meetings are with semiconductor vendors due to the vast number...

Jitter peaking and PLLs.(Phase locked loops)
September 13, 2007... by Gary Giust, PhD My audiophile brother prizes his tube transistors and vinyl-record collection. It doesn't bother him that every pass of the metal needle on vinyl creates friction that slowly degrades his records' fidelity. Engineers...

Distributed linear regulators increase output current and spread the heat.
September 13, 2007... by Robert Dobkin, Linear Technology Corp Parallel-board layout and heat spreading provide designers new ways to use linear regulators in all-surface-mount approaches. These techniques work well in today's high-performance, high-density...

USB-powered RF-power sensor combines most measurement functions.
September 13, 2007... by Dan Strassberg Agilent Technologies has announced the U2000 Series of USB-based 9-kHz to 24-GHz power sensors, which are smaller, lighter, and less expensive than typical power meters and similar power-sensing instrumentation. Because...

Video-codec cores offer programmability.
September 13, 2007... by Ron Wilson As more and more devices-from cell phones to surveillance cameras to robots-require video capture, video codecs are becoming almost standard building blocks for SOCs (systems on chips). Given the complexity of the computing...

Cadence and Mentor create free, open-source SystemVerilog methodology.
September 13, 2007... by Michael Santarini In an effort to make it easier for users to create interoperable SystemVerilog verification flows, Cadence Design Systems and Mentor Graphics have jointly created and are announcing that they will standardize on the...

Processor lowers the cost and power thresholds for HD video.
September 13, 2007... by Robert Cravotta The TMS320DM355 processor is the latest addition to Texas Instruments' DaVinci processor family. Unlike previous DaVinci devices, this processor does not include a software-programmable DSP. Rather, it couples an...

Module controls four network channels.(MEN Micro Inc.)(3U CompactPCI network controller)(Brief article)
September 13, 2007... by Warren Webb A new 3U CompactPCI network controller from MEN Micro offers four fast Ethernet ports for control of multiple network configurations, including firewalls, gateways, routers, and fieldbus-data concentrators. The single-slot...

Reference design prevents power theft.
September 13, 2007... by Margery Conner Some people respond to the high cost of energy by stealing it. To prove that fact, Metering.com recently published a report showing that, in some countries, tampering with meters accounts for 5% of illegally consumed...

Los Alamos lab makes major step in quantum-dot lasers.
September 13, 2007... by Ron Wilson Victor I Klimov, PhD, leads a team at Los Alamos National Laboratory that has been working for a number of years on turning NQDs (nanocrystal quantum dots) into lasers. Because the dots are so small, their size influences the...

Silicon nanocrystals promise 40% solar-cell efficiency.
September 13, 2007... by Ron Wilson A research team at the NREL (National Renewable Energy Laboratory) claims to have observed production of two to three electrons from a single photon in a silicon nanocrystal. The result is potentially highly significant for...

Nanostructures enable paperlike supercapacitors and batteries.
September 13, 2007... by Ron Wilson The carbon nanotube has made another appearance in the literature, this time giving researchers quite a charge. Researchers at Rensselaer Polytechnic Institute have reported the use of the structures in creating a family of...

Scope.(Javits Center held Audio Engineering Society conference)(Wooldridge Corp designed digital computer)
September 13, 2007... Edited by Ron Wilson Looking Ahead To the 123rd US AES Convention The Javits Center in New York hosts the 123rd US AES (Audio Engineering Society) Convention for all things audio from Oct 5 through 8. Technical sessions span the...

Start-up customers: diamonds in the rough.
September 13, 2007... Edited by Suzanne Deffree A diamond in the rough may be a hard find, but Avnet Electronics Marketing (Avnet EM, www.em.avnet.com ) believes it is worth the search. Avnet EM recently set out on such a search and came across Black Diamond...

Outsourcing by OEMs pushes EMS, ODM growth.
September 13, 2007... Edited by Suzanne Deffree Current dynamics in the electronics-contract-manufacturing market point to further outsourcing by OEMs (original-equipment manufacturers), and, as a result, both EMS (electronics-manufacturing-service) providers...

Norway POHS casts wide net.(prohibition on certain hazardous substances)(Brief article)
September 13, 2007... Edited by Suzanne Deffree Norway is casting a wide net with its latest environmental directive, a set of ROHS (restriction-of-hazardous-substances)-like rules that aim to restrict or ban 18 substances used in consumer goods. Norway's...

Reach out and touch.
September 27, 2007... by Bonnie Baker As the old AT&T slogan used to say, all you have to do is pick up a phone to 'reach out and touch someone.' Even for engineers, something as simple as this type of analog conversation can immediately clarify the most...

Electronics in auto racing: friend and foe.
September 27, 2007... by Warren Webb, Technical Editor Although embedded-system technology improves almost every aspect of motor sports, race officials often ban it during competition in the interest of fairness. Electronic systems have been major...

Solid-state storage: feasible plan or flash in the pan?
September 27, 2007... by Brian Dipert, Senior Technical Editor Flash memory's per-megabyte cost is plummeting, and its per-chip density is climbing. Your customers' demands for system performance, low power consumption, compact form factors, light weight,...

Single op amp achieves double-hysteresis-transfer characteristic.
September 27, 2007... Herminio Martínez, Encarna García, and Juan Gámiz, Technical University of Catalonia, Barcelona, Spain Edited by Charles H Small and Fran Granville In process-control applications requiring discontinuous...

Integrator ramps up/down, holds output level.
September 27, 2007... Glen Chenier, TeeterTotterTreeStuff, Allen, TX Edited by Charles H Small and Fran Granville Op-amp integrators can ramp to saturation, and a capacitor-discharge switch can reset them. Alternatively, you can input-switch them to ramp up...

Switcher adds programmable- PWM-duty-cycle clamp.
September 27, 2007... Michael O'Loughlin, Texas Instruments, Nashua, NH Edited by Charles H Small and Fran Granville Power-supply applications require the use of a duty-cycle clamp. Such applications include those using current-sense transformers and...

Circuit provides low-cost QAM mapping and translation.(quadrature-amplitude-modulation)(Brief article)
September 27, 2007... Pieter Demuytere, Cedric Melange, Elena Matei, Els De Backer, Johan Bauwelinck, and Jan Vandewege, Ghent University, Department of Information Technology, Ghent, Belgium Edited by Charles H Small and Fran Granville This Design Idea...

Reach is key to broadband-based innovation.
September 27, 2007... By Maury Wright, Editorial Director Watch the popular press, and you will constantly hear about how far behind the United States is when it comes to broadband deployment and the more recent move to 100-Mbps and faster data rates. The...

Video surveillance: It's all about computing power.
September 27, 2007... by Ron Wilson, Executive Editor Placing an area under video surveillance means setting up lots of cameras. But that's the easy part. The system must concentrate the signals from those cameras for transmission back to a central hub, using...

Transforming motion: field-oriented control of ac motors.(field-oriented control)
September 27, 2007... by Aengus Murray, International Rectifier FOC principles simplify the analysis of ac machines and allow good dynamic control of the machine flux and torque. Once the control method of choice only in high-performance industrial ac-servo...

Designing small, efficient ac/dc switching power supplies.
September 27, 2007... by Hiren Shah, XP Power Power supplies must perform to their specifications as well as meet international standards with respect to EMC performance, safety, and input protection. These tips involve saving space without compromising...

Low-power VME board sports dual processors.
September 27, 2007... by Warren Webb Targeting low-power, computationally intensive applications within the defense, industrial-control, and transportation markets, Concurrent Technologies recently announced a single-slot VME single-board computer, which...

Humble solder paste enables exotic heat-transfer devices.(Engineered Fluid Dispensing)(Brief article)
September 27, 2007... by Margery Conner EFD has introduced the nondrip SAC305 solder paste for gap filling and application on vertical surfaces in heat-transfer applications. Although news on this technology emphasizes the use of heat sinks, spreaders, and...

Economical RF-vector-signal analyzer achieves top measurement speed.
September 27, 2007... by Dan Strassberg Agilent Technologies has introduced its EXA RF-VSA (vector-signal analyzer), which the company says sets a new standard for value in its field. According to Agilent, the EXA is the industry's fastest economy-class signal...

PCIe Gen2 boosts lane rates to 500 Mbytes/sec.
September 27, 2007... by Maury Wright The second generation of PCIe (Peripheral Component Interconnect Express) technology is upon us with vendors planning new IC families and support chips. Meanwhile, PCIe 1.1 technology moves to enable embedded-system...

Handheld cable-and-antenna tester focuses on field engineers, technicians.
September 27, 2007... by Dan Strassberg Agilent Technologies has introduced the handheld, battery-operated N9330A cable-and-antenna tester, which provides basic performance and optimized usability for installation and maintenance of wireless and cabled...

Multicore processor features 64 programmable cores.(Tile64 processor)(Tilera corp)
September 27, 2007... by Robert Cravotta Tilera based its Tile64 processor on a mesh-multicore architecture that can scale to thousands of cores. The processor is the first silicon instantiation of the architecture, and it contains 64 programmable cores. Each...

Free Multisim SPICE tool eases ADI-based design.
September 27, 2007... by Maury Wright ADI (Analog Devices Inc) and National Instruments' Multisim group have teamed up to provide a free download of a special version of the Multisim SPICE tool that comes with models of ADI op amps and other linear components....

Mark Wecht: Embedding high-performance technology.
September 27, 2007... by Warren Webb Mark Wecht is founder and chief executive officer of ESD (Embedded Systems Design, www.embedded-sys.com ), where he and his engineering staff constantly push the technology envelope in high-performance...

Scope.(conference on hazardous materials )(Mathematical Analyzer Numerical Integrator and Computer )
September 27, 2007... Edited by Ron Wilson Looking Ahead To the Power Electronics Technology Conference Opening Oct 30 and running through Nov 1 in Dallas, the Power Electronics Technology Exhibition and Conference has retuned, its sponsors say, to...

Time bomb.(maintainance of transistors)(Viewpoint essay)
September 27, 2007... by Walter Lindenbach, Calgary Controls Ltd There is a failure mode that is worse than intermittent; no tests, measurements, or parts replacement will directly reveal the cause. You can test the circuit on the bench and in the field for...