Ferrite Out Better Core Materials For Your POL Design

Power architectures with nonisolated voltage regulation continue to evolve, and power inductor designs are fundamental to the success of the new product designs. The trend toward two-stage conversion with nonisolated point-of-load (POL) modules is fueling the demand for low-profile, high-power surface-mount inductors with current ratings up to 25 A. Power system design engineers have a wide variety of power inductors at 8 A and higher to choose from when working on a new design. This can be rather overwhelming for a new designer because datasheets can be confusing, and an experienced designer may not be aware of some of the newer core materials available such as powdered iron and ferrite materials. These materials can help reduce size, cost and power losses.


The Right Material for the Right Job

As power densities and current levels continue to increase and more competitors enter the market, product performance becomes critical for successful product sales. For the magnetics design engineer seeking to minimize power losses, the core material selection and physical package size are critical. The job becomes even more difficult as the size of the device decreases and the current increases.

The Right Material for the Right Job

The most common core materials are listed in Table 1. These materials have been around for a long time, but manufacturers are continuously developing new ones. The basic core material ingredient is iron, but it is the alloy blends or oxide formulations and the process controls that give materials their unique performance characteristics. Even though there are many categories, the majority of the materials are considered powdered irons. Categories 1 through 5 in Table 1 outline powdered irons.


Each material category occupies a niche where it is the best material for a given design application. If cost is the critical factor in the design application, then powdered iron is the traditional choice. Table 2 depicts a core material cost comparison using standard powdered iron as the benchmark.


The cost multiplier has been declining in recent years for the ferrite, powdered alloy and high flux materials, because more vendors are developing new materials and selling this type of product. The molypermalloy (MPP) material is cost-restrictive for most applications; however, it is often used for low-volume, height-restrictive applications where a toroidal shape is required. MPP manufacturers are starting to expand their MPP offerings into EIR core shapes, but this product will probably remain too expensive for most high-volume, high-current inductor designs.

Source:www.powerelectronics.com

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FDA Introduces New Technology to Improve Food Security

The Food and Drug Administration today announced further steps to use modern technology to provide new protections for America’s food supply. First, FDA announced that its new electronic registration system for food facilities, foreign and domestic, will be “live” today at 6 p.m. Eastern Daylight Time. This registration system, available online at http://www.cfsan.fda.gov/~furls/ovffreg.html and designed to bolster the safety and security of America's food supply, will help with quick identification and notification of food processors and other facilities involved in any deliberate or accidental contamination of food. Second, FDA issued a report to Congress on its progress toward developing more rapid, easier, and less costly tests to detect food contamination.

FDA’s registration system, one of the key provisions of the Public Health Security and Bioterrorism Preparedness and Response Act of 2002 (the Bioterrorism Act), is part of an interim final rule announced by Secretary of Health and Human Services Tommy G. Thompson October 9 and published on October 10 that requires domestic and foreign food facilities to register with the agency by December 12, 2003. As a result, FDA will have for the first time an official roster of foreign and domestic food facilities, allowing timely notification and response in the event of a food safety threat.

“FDA is committed to developing new, more efficient ways to enhance food security, and the new electronic registration system we are inaugurating today reflects that commitment,” said Mark B. McClellan, M.D., Ph.D., Commissioner of Food and Drugs. “Registering online will be fast and simple. Our site will be open 24 hours a day, seven days a week, available to anyone in the world with access to the internet. This new system will permit 400,000 facilities to register worldwide in 60 days, and will give FDA new capabilities to work with everyone involved in our food supply to keep it safe and secure.”

FDA is encouraging electronic registration because it is faster and more efficient than paper registration. Each firm registering online will instantly receive its unique registration number, which will be required for doing business in the U.S. beginning December 12. (Paper registration may be submitted via regular mail or fax.) Facilities will not be charged for registration, which is a one-time procedure.

In addition to the registration rule, FDA last week published a second interim final regulation to enhance the safety and security of the food supply. That rule requires that FDA be provided advance notice of shipments of human and animal food being imported or offered for import into the U.S, also effective as of December 12, 2003.

In arriving at the interim final rule, the FDA worked closely with the Bureau of Customs and Border Protection (CBP) to ensure the new regulations promote a coordinated strategy for border protection. FDA and CBP continue to collaborate intensely on making the new safeguard of prior notice as efficient and effective as possible.

For example, FDA and CBP have worked together so that most notices can come in through the existing CBP system. In addition, FDA and CPB have signed a Memorandum of Understanding to commission CBP employees to serve on FDA’s behalf at ports where FDA may not currently have staff or to augment FDA staff in the enforcement of FDA’s prior notice regulation. FDA plans to co-locate its Prior Notice Review Center and staff at CBP’s National Targeting Center. This will ensure that the agencies maximize their joint assets and provide consistent enforcement. It further engenders a common bond, so that the two agencies most responsible for protecting the nation’s imported food supply can interact in person.

FDA and CBP are also working together to develop enhanced information systems and programs to keep food imports secure without imposing unnecessary costs or delays. FDA and other federal agencies continue to contribute to the development of CBP’s state-of-the-art automated commercial environment system to screen products and to support FDA’s public health mission.

“Not only have FDA and the Bureau of Customs and Border Protection forged a stronger working relationship, but we have also listened carefully to stakeholders across the board to provide an unprecedented level of food security as efficiently as possible,” said Dr. McClellan. "We will continue to work with all affected parties to help them understand how to do their part in assuring food safety at the lowest possible cost.”

FDA has already begun an extensive domestic and international outreach and education about the new rules. In the coming weeks, FDA will conduct national and international meetings and other programs to provide a comprehensive picture of the rules. As part of this effort, FDA also will hold a satellite downlink public meeting on Oct. 28 to discuss the two regulations. Information about this meeting, including domestic and international viewing opportunities and registration, is available at http://www.fda.gov/oc/bioterrorism/bioact.html.

In another step to improve the technologies available to keep the nation’s food supply safe and secure, FDA today sent to Congress a report detailing progress it has made in research to develop rapid tests and sampling methods to improve the agency’s ability to identify contamination of food.

The report, entitled “Testing For Rapid Detection of Adulteration Of Food,” responds to provisions in Section 302(d) of the Bioterrorism Act. That section charged FDA with developing faster methods to detect adulterated foods and animal feed at U.S. ports of entry so as not to delay unduly the flow of food to domestic markets. This is the first annual report to Congress as required under the Bioterrorism Act.

“Improving FDA’s inspection, detection and monitoring capabilities of food imports is a top priority,” said Dr. McClellan. “With our research partners in private industry, other government agencies, academia, trade associations, and others, FDA is conducting a considerable amount of research intended to develop new test methods and innovative test kits. Our goal is to make them faster, more economical, and more accurate, so that we can be better prepared at a lower cost.”

According to the report, FDA currently has over 90 different active research projects involving test and sampling methodology development. This is an FDA-wide effort and involves many FDA scientific experts and partners in academia and consortia to achieve this important and strategic research goal. Some of the research highlights are provided below:

Center for Food Safety and Applied Nutrition

Developing and validating effectiveness of rapid testing technology and methods for detecting potential biological, chemical and radiological threat agents in foods
Developing and assessing processing technologies and systems that may mitigate or eliminate potential biological and chemical threats to the food supply
Center for Veterinary Medicine

Successfully validated an analytical method using polymerase chain reaction (PCR) tests to detect bovine-derived materials in animal feeds to ensure compliance with FDA’s regulation designed to protect the U.S. against bovine spongiform encephalopathy (BSE, or “mad cow disease)
Worked to expand the number of species that the current PCR method is capable of detecting from bovine to include other ruminant species.
Office of Regulatory Affairs

Developed an immunoassay method for detection of botulism toxin in food.
Developed a mass spectrometry-based method for detecting a wide variety of chemical toxins in food.
National Center for Toxicological Research

Developed a novel approach to rapidly identify biomarkers of toxicity using a mass spectrometry-based method for detecting microorganisms that could be introduced into otherwise harmless organisms to cause intentional adulteration.
“The one-time allocation of $5 million provided last July by the Office of Management and Budget is allowing FDA to strengthen this research program,” said Dr. McClellan. “Because testing select agents in food represents a new field of scientific inquiry, the research needs are quite substantial and will need to be sustained over several years.”

Source:www.fda.gov

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Cheap, Superefficient Solar

Technologies collectively known as concentrating photovoltaics are starting to enjoy their day in the sun, thanks to advances in solar cells, which absorb light and convert it into electricity, and the mirror- or lens-based concentrator systems that focus light on them. The technology could soon make solar power as cheap as electricity from the grid.


The idea of concentrating sunlight to reduce the size of solar cells--and therefore to cut costs--has been around for decades. But interest in the technology has picked up in the past year. Last month, Japanese electronics giant Sharp Corporation showed off its new system for focusing sunlight with a fresnel lens (like the one used in lighthouses) onto superefficient solar cells, which are about twice as efficient as conventional silicon cells. Other companies, such as SolFocus, based in Palo Alto, CA, and Energy Innovations, based in Pasadena, CA, are rolling out new concentrators. And the company that supplied the long-lived photovoltaic cells for the Mars rovers, Boeing subsidiary Spectrolab, based in Sylmar, CA, is supplying more than a million cells for concentrator projects, including one in Australia that will generate enough power for 3,500 homes.


The thinking behind concentrated solar power is simple. Because energy from the sun, although abundant, is diffuse, generating one gigawatt of power (the size of a typical utility-scale plant) using traditional photovoltaics requires a four-square-mile area of silicon, says Jerry Olson, a research scientist at the National Renewable Energy Laboratory, in Golden, CO. A concentrator system, he says, would replace most of the silicon with plastic or glass lenses or metal reflectors, requiring only as much semiconductor material as it would take to cover an area the size of a typical backyard. And because decreasing the amount of semiconductor needed makes it affordable to use much more efficient types of solar cells, the total footprint of the plant, including the reflectors or lenses, would be only two to two-and-a-half square miles. (This approach is distinct from concentrated thermal solar power, which concentrates the heat from the sun to power turbines or sterling engines.)


"I'd much rather make a few square miles of plastic lenses--it would cost me less--than a few square miles of silicon solar cells," Olson says. Today solar power is still more expensive than electricity from the grid, but concentrator technology has the potential to change this. Indeed, if manufacturers can meet the challenges of ramping up production and selling, distributing, and installing the systems, their prices could easily meet prices for electricity from the grid, says solar-industry analyst Michael Rogol, managing director of Photon Consulting, in Aachen, Germany.


But the approach has been difficult to implement. "It has not delivered on the promise, mostly because of the complexity of the systems," Rogol says. The goal is to engineer a concentrating system that focuses sunlight, that tracks the movement of the sun to keep the light on the small solar cell, and that can accommodate the high heat caused by concentrating the sun's power by 500 to700 times--and to make such a system easy to manufacture.

Source:www.technologyreview.com

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Cognitive Radio

Growing numbers of people are making a habit of toting their laptops into Starbuck's, ordering half-caf skim lattes, and plunking down in chairs to surf the Web wirelessly. That means more people are also getting used to being kicked off the Net as computers competing for bandwidth interfere with one another. It's a local effect -- within 30 to 60 meters of a transceiver -- but there's just no more space in the part of the radio spectrum designated for Wi-Fi.

Imagine, then, what happens as more devices go wireless -- not just laptops, or cell phones and BlackBerrys, but sensor networks that monitor everything from temperature in office buildings to moisture in cornfields, radio frequency ID tags that track merchandise at the local Wal-Mart, devices that monitor nursing-home patients. All these gadgets have to share a finite -- and increasingly crowded -- amount of radio spectrum.

Heather Zheng, an assistant professor of computer science at the University of California, Santa Barbara, is working on ways to allow wireless devices to more efficiently share the airwaves. The problem, she says, is not a dearth of radio spectrum; it's the way that spectrum is used.

The Federal Communications Commission in the United States, and its counterparts around the world, allocate the radio spectrum in swaths of frequency of varying widths. One band covers AM radio, another VHF television, still others cell phones, citizen's-band radio, pagers, and so on; now, just as wireless devices have begun proliferating, there's little left over to dole out.

But as anyone who has twirled a radio dial knows, not every channel in every band is always in use. In fact, the FCC has determined that, in some locations or at some times of day, 70 percent of the allocated spectrum may be sitting idle, even though it's officially spoken for.

Zheng thinks the solution lies with cognitive radios, devices that figure out which frequencies are quiet and pick one or more over which to transmit and receive data. Without careful planning, however, certain bands could still end up jammed. Zheng's answer is to teach cognitive radios to negotiate with other devices in their vicinity. In Zheng's scheme, the FCC-designated owner of the spectrum gets priority, but other devices can divvy up unused spectrum among themselves.

But negotiation between devices uses bandwidth in itself, so Zheng simplified the process. She selected a set of rules based on "game theory" -- a type of mathematical modeling often used to find the optimal solutions to economics problems -- and designed software that made the devices follow those rules. Instead of each radio's having to tell its neighbor what it's doing, it simply observes its neighbors to see if they are transmitting and makes its own decisions.

Source:www.techreview.com

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Electricity from Sugar Water

A new way to make hydrogen directly from biomass, such as soy oil, reported in the current issue of Science, could cut the cost of electricity production using various cheap fuels.


Researchers at the University of Minnesota have developed a catalytic method for producing hydrogen from fuels such soy oil and even a mixture of glucose and water. The hydrogen could be used in solid-oxide fuel cells, which now run on hydrogen obtained from fossil-fuel sources such as natural gas, to generate electricity. Further, by adjusting the amount of oxygen injected along with the soy oil or sugar water, the method can be adapted to make synthesis gas, a combination of carbon monoxide and hydrogen that can be burned as fuel or converted into synthetic gasoline. The method can also produce chemical feedstocks, such as olefins, which can be made into plastics.


Although the results are preliminary, the new catalysis process represents a fundamentally new way to directly use soy oil and other cheap biomass as fuels; such biomass now needs to be converted into biodiesel or ethanol in order to be used as fuels. "Generally, people have steered clear of nonvolatile liquids--materials that you cannot vaporize," since these typically produce a carbon residue that stops the process of producing hydrogen, says Ted Krause, head of the basic and applied research department at Argonne National Laboratory, in Argonne, IL. By eliminating the need to process soy oil and sugar water to make volatile fuels such as ethanol, the new method "opens up the number of available biomaterial feedstocks," he says.


The process begins when the researchers spray fine droplets of soy oil or sugar water onto a super-hot catalyst made of small amounts of cerium and rhodium. The rapid heating combined with catalyst-assisted reactions prevents the formation of carbon sludge that would otherwise deactivate the catalyst. And the reactions produce heat, keeping the catalyst hot enough to continue the reaction. As a result, although fossil fuels are used initially to bring the catalysts up to the 800 °C working temperature, no fossil fuels are needed to continue the process. "One of the virtues of our process is it requires no external process heat--it drives itself," says chemical-engineering and materials-science professor Lanny Schmidt, who led the research.

Source:www.technologyreview.com

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Super-vivid, super-efficient displays

Your next MP3 player may sport more-vivid color displays and longer-lasting batteries. That's because a major manufacturing effort by South Korea's Samsung SDI could help bring a display technology called organic light-emitting diodes, or OLEDs, into the mainstream. Until now, OLED displays have not been manufactured in high volumes, and applications have generally been limited to Asian markets.


OLEDs are based on a light-emitting conductive organic molecules that consumes one-half to one-fifth of the power of liquid-crystal displays (LCDs). Displays using OLEDs present more-vivid colors and allow for clearer videos, thanks to a faster "refresh rate." As the technology matures and cheapens, it could ultimately replace current computer-monitor and television technologies.


While other electronics companies are in the planning stages for ramping up manufacture and adoption of OLEDs, Samsung is spending $500 million to build an OLED factory that will begin production next year. Samsung hopes to churn out between one million and two million displays per month, initially for cell phones and other mobile devices that would move beyond Asian markets, says Barry Young, an industry analyst.


The Samsung effort (see Samsung's technology explainer here) includes technology from Universal Display, of Princeton, NJ, which pioneered an OLED variant that uses phosphorescent molecules to produce the reds, blues, and greens necessary for a color display with very high efficiency.


Stephen Forrest, vice president of research at the University of Michigan, whose research group (originally at Princeton University) licensed its OLED technology exclusively to Universal Display, believes the Samsung factory is a huge milestone. "We are at a very critical frontier," he says. "This is a good technology, and people know it, so now it's a matter of getting more companies committed to entering into manufacturing. To make a better, cheaper, more efficient display is a very important part of our everyday life."

Source:www.technologyreview.com

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LED Driver Supports Multi-Mode Operation

Catalyst Semiconductor’s high-power, 500-mA inductive boost LED driver is designed for Movie/Flash mode applications. The CAT4134 offers a fully integrated Movie/Flash switching function, which allows designers to set the exact Flash and Movie modes required via a single resistor, minimizing the need for external circuitry. Capable of driving up to six white/color LEDs, the CAT4134 is ideal for increasing efficiency and simplifying the design of video lighting applications.


The new Catalyst inductive boost LED driver offers dual channel outputs, which provide matched LED currents of up to 250 mA per channel. Output current levels are controlled by one of two resistors, RSET or RFLASH. When the flash input pin is low (Movie mode), RSET controls the LED current. When the flash input pin is high (Flash mode), the resistor RFLASH controls the LED current. Each channel drives two or three white LEDs in series and provides a regulated current to control LED brightness. Input supply down to 3 V is supported, making the device ideal for Li-Ion battery applications.


High frequency, low noise operation allows the CAT4134 to be used with small external inductors and ceramic capacitors while retaining up to 85% efficiency. When disabled the device can be placed into a “Zero” quiescent mode via a shutdown pin, eliminating battery drain when not in use.


The CAT4134 is available in a 3-mm x 3-mm, 12-pin TDFN RoHS-compliant package. Pricing for 10,000-piece quantities is $0.88 each. Samples and evaluation kits are now available.

Source:www.powerelectronics.com

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Thermal Solutions Provider Licenses Heat Transfer Technologies

Celsia Technologies has entered a multi-year agreement with Taiwan-based Yeh-Chiang Technology (YCTC), a manufacturer of heat pipes. Under the terms of the agreement, YCTC will manufacture Celsia’s thermal management products in China. YCTC will also license Celsia’s patented thermofluidic technology to offer to its key OEM customers.


“Celsia’s technology is exactly what the market needs today,” said John Yang, founder of YCTC. “With Celsia’s new vapor chamber technology and its thin, flat form factors, customers can have greater flexibility and simplicity in their electronic designs and assemblies. We believe this technology is the next step for electronics heat transfer, and it will provide great differentiation to our customers.”


“We are building partnerships across the electronics supply chain so that in addition to our strong technical position, Celsia is equally strong in its distribution and supply network,” said George Meyer, Celsia’s chief marketing officer and general manager of the Americas and Europe. “YCTC is an excellent heat pipe manufacturer with a laser focus on manufacturing two phase heat transfer products. The combination of Celsia technology and YCTC manufacturing will be a formidable force in the market.

Source:powerelectronics.com

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Rerouting Brain Circuits with Implanted Chips

New, implantable and wireless brain chip can create artificial connections between different parts of the brain, paving the way for devices that could reconnect damaged neural circuits. Scientists say the chip sheds light on the brain's innate ability to rewire itself, and it could help explain our capacity to learn and remember new information.


"We have a chance of manipulating and repairing [specific] regions of the brain that might be damaged," says Joseph Pancrazio, director of the neural-engineering program at the National Institute of Neurological Disorders and Stroke in Bethesda, MD. "To be able to repair these kinds of lesions on a neuron-by-neuron basis is extraordinary."


In stroke and spinal-cord injuries, neural circuits may be damaged, leaving patients with profound problems in movement or speech. In recent years, scientists have begun developing brain-cognitive interfaces, which record neural signals and transmit them either to a computer, to another part of the brain, or to another body part in effort to get around the neural blockade.


In the new study, researchers from the University of Washington, in Seattle, showed for the first time in live animals that an implantable device could record signals from one part of the brain and transmit that information to another part, reshaping neural connections in the process. "We essentially set up an artificial-feedback loop between two different parts of the cortex," says Eberhard Fetz, the scientist who led the study.


The device, built entirely of off-the-shelf parts, consists of tiny wire electrodes surgically implanted into a monkey's motor cortex. (Neurons in this area are active when an animal makes a voluntary movement.) The wires record activity from these cells and send the signals to a tiny printed circuit board, which amplifies and processes the signal. That information is then sent to a neighboring circuit board and electrode, which uses the signal to stimulate cells in another part of the motor cortex. The entire apparatus is encased in titanium and attached to the monkey's head, allowing the animal to go about its normal daily activities.


According to research published online in Nature, the device was able to reshape the neural circuits that control muscle movement. At the start of the experiment, neurons at the recording sites triggered movement of the wrist in a different direction than when neurons at the stimulating site were activated. After running the record-stimulate sequence for 24 hours in freely behaving monkeys, researchers found that underlying neural circuits had changed: the wrist movement associated with neurons at the stimulating site more closely resembled the movement associated with neurons at the recording area, indicating that the neural connections between these two areas had strengthened.

The findings support a long-held theory in neuroscience: that activating different brain cells at the same time strengthens connections between those cells. Scientists believe this concept underlies our ability to both learn new information and recover some motor and cognitive function after strokes and other brain injuries. "The findings show that the current conception of long-term strengthening is very much on the right track," says Krishna Shenoy, a neuroscientist at Stanford who is also developing neural implants

Source:www.technologyreview.com

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TPS40140 Synchronous PWM Controller

Although new technologies based on digital power control promise to be disruptive technologies in the long run, mainstream analog control technology can still have a significant and immediate impact on power system designs. Such can be said for this year's Power Electronics Technology Product of the Year award winner. The TPS40140 synchronous PWM controller from Texas Instruments (TI) is, at heart, an analog controller. However, because of its clever design techniques, the chip simplifies the potentially complex task of paralleling voltage sources to create scalable point-of-load (POL) power designs.

The TPS40140 features a unique characteristic that the vendor calls “stackability.” That term describes the way multiple controller ICs can be combined in a single design either to scale current levels on a given output or to add additional voltages. A single TPS40140 can be configured to generate two independent outputs or configured as a 2-phase controller with a single output. Then, by stacking or paralleling controller chips, designers can increase current output on a given voltage rail. The controller supports up to 16 phases of interleaved operation for up to 320 A of output.

The resulting design can be a mix of single- and multi-phase outputs (see the figure). Interleaved operation not only permits the scaling of current levels, but also reduces ripple current and requirements for input and output capacitance.

Although existing multiphase controllers can be cascaded to scale the number of phases, they typically employ an analog interface to control phasing of the different outputs. In contrast, the TPS40140 employs a unique digital interface to control phasing, which makes the designs less sensitive to noise and eases pc-board layout.

In a multicontroller, multiphase design, one channel generates a master clock (CLKIO). This clock is distributed to the slave channels, which use it to generate their PWM clocks. The master clock runs at eight times the frequency of the slave PWM clock. In other words, within each master clock signal there are eight frames (seven clock pulses plus a missing pulse for synchronization), and each PWM slave clock will trigger on a different frame depending on the phase number assigned to that PWM channel. That phase number is programmed using a simple voltage divider connected to the phase select pin on each channel.

In designing this part, TI overcame several design challenges. According to Stefan W. Wiktor, dc-dc controller design manager at TI, one of the most difficult was achieving good current balance among phases when the phases are generated across multiple controller chips. This is because of the difficulty in matching PWM ramp signals from chip to chip. TI addressed this problem using a frequency-to-current converter that makes the PWM ramp signal independent of semiconductor process-related parameters, except for reference voltage, which is very controllable.

Though just introduced in August 2006, the TPS40140 has already experienced design wins at two major power-supply companies, a large server manufacturer and a test equipment manufacturer. However, Tim Goodrow, product marketing manager for dc-dc modules at TI, observes that customers are adopting the TPS40140 because of the ease with which this controller implements multiphase control, more so than for its flexibility in generating multiple voltages.

Source:www.powerelectronics.com

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Rectifier IC boosts

Increasing system efficiency by 1% over discrete solutions, the IR1166 SmartRectifier IC simplifies the design of mid-power secondary synchronous rectification (SR) circuits of resonant half-bridge converters and flyback converters designed for 50 to 150-W discontinuous conduction mode, critical conduction mode, and continuous conduction mode. The part uses a technique for precise, direct sensing of voltage thresholds across the SR MOSFETs.

Specifications include a VCC of 20 V, a VFET of 200 V, a maximum switching frequency of 500 kHz, a gate drive of 1/–3.5 A, a VGATE clamp voltage of 10.7 V, and a maximum sleep current of 200 µA. The part is housed in an SO-8 package and will soon be in a DIP-8 package. The IRAC116-100W flyback reference design is also available. ($0.70 ea/10,000—available now.)

Source:www.electronicproducts.com

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Automotive Applications

Product development services for a range of automotive applications, including mobile satellite communications and automotive cruise control radars.

For satellite communications applications, ERA has pioneered the use of unique low cost, very low profile scanning antennas. Designed initially for reception of satellite TV services in Ku-Band, the technology is being used on recreational vehicles, sports utility vehicles, buses, coaches and trains. The technology can readily be extended to higher frequency bands, for example to serve future interactive services in Ka-Band.
Low profile satcom antenna designed by ERA in collaboration with Winegard
ERA has applied its novel twist reflector antenna technology to Automotive Cruise Control Radar systems which operates in the 77GHz band. Using its unique manufacturing processes, ERA has been able to incorporate a total of eight high performance antennas into a single housing.

This housing is also used to accommodate the RF electronics and to provide heat sinking for the high power components. De-icing of the radome is also possible. Production costs are compatible with application of the sensor system across a wide range of automotive platforms.

Source:www.era.co.uk

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Single-chip receiver for mobiles handles TV and radio

Start-up Mirics Semiconductor describes its new MS1001 RF-tuner IC (Picture) as a "polyband" device for mobile digital-broadcast reception. Although several companies have recently made announcements that focus on the mobile-TV sector, Mirics says that its chip has much wider applicability, covering multiple broadcast standards. The chip covers broadcast bands ranging from 100 kHz to 1.9 GHz.

The primary target market is the mobile phone. The company forecasts that, by 2009, some 20% of all phones will have mobile TV, but a much higher proportion will have radio capability, and the fraction that does have TV will encompass numerous standards. Mirics aims to provide the receiver function for TV and radio at the same cost and power level as FM radio alone. All the chip's signal processing is analog, and the chip reconfigures and reconnects its on-chip functional blocks in response to external commands, depending on the band and signal type. This reconfiguration extends to the basic architecture of the receiver function. In some cases, the receiver uses a direct-conversion, zero-IF layout; in others, it uses a conventional heterodyne architecture. The MS1001 has five RF inputs with individual on-chip low-noise amplifiers. It yields quadrature output signals, and you use a three-wire serial digital port to control the device's configuration, which you can change dynamically. As well as providing a single receiver chip for all bands, Mirics asserts that its product is the cheapest and lowest power device available, at $3.50 (10,000). Mirics aims to further reduce the cost to make the device competitive with chips that provide the FM function alone and to exploit mixed-signal capability to add a flexible on-chip digital demodulation capability

Source:www.edn.com

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SOG LCD modules

Targeting high-resolution portable products such as PDAs and GPS units, a family of 2.7- and 3.5-in. system-on-glass (SOG) LTPS LCD modules delivers a resolution of up to 640 x 480 pixels. Available in both transflective and transmissive configurations, the 70%color gamut switching VGA/QVGA devices include a touch panel and can display up to 16.19 million colors using a built-in step interpolation circuit.

The transmissive 3.5-in. 229-ppi LCD has a luminance of 250 nits and a contrast of 400:1, and the 2.7-in. 302-ppi LCD 200 nits at 400:1 contrast. The transflective versions offer a brightness of 200 nits with the 3.5-in. screen, and 180 nits at 2.7 in. (Call for pricing—available Feb. 2007.)

Source:www.electronicproducts.com

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14-Channel Clock ICs Boast Low Phase

The AD9516 series of clock ICs features low-phase-noise clock generation with 14-channel clock distribution at jitter levels below 1 ps. The devices integrate an integer-N synthesizer, two reference inputs, a voltage-controlled oscillator (VCO), programmable dividers, adjustable delay lines, and 14 clock drivers, including LVPECL, LVDS, and CMOS. This high level of integration eliminates several discrete components, reducing board space and costs by more than 50%, according to Analog Devices. Also, integrating the VCO on-chip greatly reduces the risks associated with the failure of discrete oscillators, improving system reliability.

The clock ICs come in five versions, each supporting a specific frequency range. The AD9516-0 includes a VCO that tunes from 2.60 to 2.95 GHz. The other parts cover lower frequencies, down to the AD9516-4's range of 1.50 to 1.90 GHz. The devices can also be used with an external VCO up to 2.4 GHz. Each unit includes six LVPECL outputs that can operate up to the VCO's maximum rate, as well as four/eight outputs that can be programmed to either LVDS (four outputs max) or CMOS (eight outputs max) levels. In LVDS mode, the outputs operate to 1 GHz, and in CMOS mode they operate to 250 MHz. The devices come in 9- by 9-mm, 64-lead lead-frame chip-scale packages.

Source:www.elecdesign.com

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Digital Signal Controllers Expand Options for Power Conversion and Motor Control

Texas Instruments has expanded its TMS320C2000 family of digital signal controllers by adding new options for on-chip memory and more PWM peripherals. The new controllers include the TMS320F2809 and TMS320F2802 flash-based controllers and custom ROM-based TMS320C2801 and TMS320C2802, which are fully hardware- and software- compatible with the three existing TMS320F280x controllers. With the wider mix of memory options, the new controllers make it easier for system designers to tradeoff memory and cost (see the table). That flexibility will aid designers as they apply these ICs in applications such as motor control, digital power conversion, intelligent sensor control and other applications in industrial, appliance, automotive, medical and consumer products.

The TMS320F2809 offers 256 kbytes of on-chip flash, double the size of the previously introduced ‘F2808. It also increases the number of PWM channels with 150-ps resolution from four to six. In addition, this flagship member of the TMS320C2000 family doubles the sampling speed on the 12-bit pipelined A-D converter to 12.5 Msamples/s. In contrast, most embedded A-D converters are typically limited to sampling rates in the single megahertz range. Furthermore, the F2809’s A-D converter boasts an effective number of bits (ENOB) of 10.9 and is valid across the full -40 to +125° C temperature range. As with other members of the TMS320C2000 family, the ‘F2809 features a 100-MIPS CPU.

The controllers’ high resolution PWMs provide 16 bits of accuracy in a 100-kHz control loop and 12 bits at 1.5 MHz. According to Texas Instruments, competing processors limit accuracy to less than 10 bits at 100 kHz and less than 6 bits at 1.5 MHz. In digital power applications, the higher resolution PWM results in a faster transient response with a smaller ripple amplitude. The high resolution PWM also eliminates ‘limit cycle’ issues, which means power supply designers are able to use digital control in high-switching frequency supplies.

Furthermore, the new combinations of performance, memory, and peripherals offered by the C28x and F28x benefit advanced motor control applications. For example, one TI customer—Self-Guided Systems—recently integrated F280x controllers into the brushless dc motors used to guide the company’s Hybrid Z self-stabilizing, autonomous lawnmower. The mower’s cutting blades triangulate their position based upon mower position and reflector location. The Hybrid Z then navigates itself and cuts grass to a pre-set length without any human intervention.

All C280x and F280x devices feature a 32-bit wide data path for superior performance and mixed 16-/32-bit instruction set for improved code density. These chips provide complete control system capabilities from signal input through the on-chip A-D converter, quadrature encoder pulse (QEP), and timer captures and compares through signal output with up to 16 independent PWM channels. Besides the 150-ps PWMs, there are as many as 10 PWM outputs with 10-ns resolution. For communications, the TMS320C2000 family offers a range of interface options including multiple CAN, I2C, UART and SPI ports.

Source:www.powerelectronics.com

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Nanotube Computing Breakthrough

The use of carbon nanotubes in ultrafast computers and other electronic devices has been stymied because batches of the material contain nanotubes with varying electronic properties. One nanotube is semiconducting, while the next is conducting. Now Northwestern University researchers have developed a reliable and potentially practical way to sort through this mess, segregating nanotubes into precisely the types needed for high-performance electronics. The advance could speed progress toward nanotube computers and has many nearer-term applications, including high-definition displays, devices for nanotoxicity testing, and solar cells.


The new process separates metallic and semiconducting nanotubes. It also segregates them by diameter (another important parameter for reliable computer chips) and eliminates contaminants, such as other forms of carbon. While the researchers expected to be able to sort nanotubes by diameter, the sorting by electronic type came as a surprise, says Mark Hersam, materials-science and engineering professor and one of the Northwestern researchers. "We didn't believe it at first," he says.


Carbon nanotubes are appealing candidates for eventually replacing silicon-based computing because of their small size and excellent electronic properties: some are semiconductors--perfect for transistors--and others are metallic conductors and could be useful as wires for connecting transistors. But getting the right electronic type "makes a big, big difference," says Mildred Dresselhaus, professor of physics and electrical engineering at MIT. Placing metallic nanotubes where there should be semiconducting nanotubes would cause the chip to fail.


So although researchers have been able to painstakingly create logic circuits using carbon nanotubes (see "Carbon Nanotube Computers"), the methods employed to sort them are "all pretty tedious," Dresselhaus says, and not something that could be scaled up for manufacturing chips with the millions of transistors needed to compete with today's computers. In addition, past methods have failed to completely separate semiconducting and metallic nanotubes, says Richard Martel, chemistry professor at the University of Montreal. Martel calls the Northwestern researchers' new approach, described this month in the new journal Nature Nanotechnology, "a breakthrough in the field."


The researchers begin by adding surfactants to a batch of nanotubes. The surfactants latch on to the nanotubes, but differences in the nanotubes' size and electronic properties cause the surfactants to assemble in different concentrations and arrangements, which in turn lead to measurable differences in density. These distinct densities can be sorted out using a well-known process called ultra-centrifugation, which involves spinning the materials at ultrafast speeds--up to 64,000 revolutions per minute

Source:www.technologyreview.com

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Wireless GroundLink® System (WGL)

Teledyne Controls’ Wireless GroundLink® System (WGL) enables aircraft operators to fully automate the recording and transmission of their flight data, therefore eliminating all risk of data loss involved with traditional manual procedures. Offering unprecedented reliability, the GroundLink solution is a unique patented system that records and wirelessly transfers flight data from the aircraft to the ground, without any media handling and human intervention.

Using a Teledyne proprietary protocol, the raw data recorded during flight is compressed, encrypted and then transmitted via cellular technology and the Internet to the airline's or Teledyne's ground-based data center for processing and analysis. With the Teledyne Wireless GroundLink solution, airlines can significantly reduce data delivery delays (the data is typically available within 10-15 minutes after an aircraft has landed, versus several days or weeks with manual data retrieval). Additional operational benefits are realized since human resources, equipment costs and data-loss associated with manual retrieval methods are virtually eliminated.

Key Features of Teledyne's Wireless GroundLink® System

A fast, reliable and cost effective solution to move data on and off the aircraft

QAR data retrieval from aircraft without human involvement

Upload software and databases into on-board aircraft systems

Data accumulated during the flight is compressed and encrypted for security

Simultaneous use of up to eight full duplex radios

Multi-band radios for world wide operation

Upgradable to support emerging cellular data standards

Multiple radio transmission reduces data transfer time

Data delivered world wide, over the Internet

No investment in the infrastructure –Uses existing infrastructure maintained by service providers

Operates in controlled frequency spectrum world wide, protected from interference

End-to-end automation on aircraft data retrieval and analysis when used in conjunction with the AirFASE® flight data analysis tool.

Source:www.teledyne-controls.com

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Instrument Ethernet links get standardized

With local area networks (LANs) becoming an enterprise necessity, virtually every desktop and rack-mounted test instrument has a LAN port for remote connectivity. The trouble is, the way test engineers must use that port varies from instrument to instrument. Now, an industry consortium is on the verge of releasing a new standard for controlling test instrumentation over LANs that will simplify the development of automated test software.

The utility of tying bench instruments together to automate test and measurement has long been proven. The venerable GPIB (general purpose instrumentation bus) has been used for more than 30 years. The interface is showing its age, however, and is being challenged by the industry's need for increasing bandwidth, faster data rates, and lower cost in its small- and medium-sized systems.

A number of potential replacements have come forward, including USB, FireWire, and the CANbus, but none has gained widespread support in the industry. This has left a void that Agilent Technologies and VXI Technology sought to fill by creating both the LXI (LAN extensions for instrumentation) standard and the LXI Consortium (www.lxistandard.org) to administer it. Many major instrument companies, including Keithley Instruments and Measurement Computing Corp., have joined the consortium since its creation in September 2004.

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Transmitted-reference methods

TR modulation technique has the advantage of sending the same pulse twice through an unknown channel where both pulses experience the same type of channel distortion and detection becomes easier with a correlation receiver. Therefore, instead of correlating the distorted received pulse with a “clean” template pulse as in PPM, both the data pulse and so called template ("reference pulse") are distorted and show high correlation at the TR receiver. Therefore, there is no need for channel estimation in TR receivers.

Furthermore, a TR receiver is self-synchronized and eliminates the need for individual pulse synchronization with locally generated templates that exists in PPM scheme. The reason is that each "reference pulse" acts as a preamble for its "data pulse" and has the advantage of providing rapid synchronization. Moreover, synchronization in TR receivers occurs after correlation between the "data pulses" and "reference pulses," thus the sampling requirements are relaxed to baseband signals. This way, the need for synchronization of the received short duration RF pulses and very fast ADCs are eliminated.

Another advantage of TR modulation to the other UWB modulation schemes is its high performance in multipath environments. TR receivers exploit multipath phenomenon to improve their performance in dense multipath and indoor channels. This is because the reference and data pulses are correlated with each other, and the multipath channel introduces a longer duration in the signal component of the received signal, thus increasing the overall signal energy at detection stage

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Samsung Electronics Develops Highly-Integrated System-on-Chip for HDTV and Digital Set-Top-Boxes

The S5H2200 is a single-chip solution that incorporates dual HD MPEG-2 decoders, which can simultaneously provide high-quality audio and video for digital broadcasts to the sub-screen as well as to the main screen, an ARM920T-based 330MHz CPU, and the company's proprietary picture improvement function, DNIe (Digital Natural Image Engine).

The S5H2200 supports various display modes such as multiple picture-in-picture (PIP) and picture-in-graphics (PIG), providing an added convenience for digital TV viewers.

It also includes 24-bit digital signal processor (DSP) for high fidelity sound, and supports multiple-input Transport Stream Decoder (TSD)for Personal Video Recorder (PVR) application. Interfaces for various peripherals such as Memory Stick, ATAPI, IEEE1394 and USB make it compatible with external inputs from other digital devices such as digital STB, DVD, game console, and digital camcorder.

Especially, "Platform-base design technology is newly applied so that each function block(CPU, A/V Decoder, DNIe, and DSP) can be independently designed and then integrated with the others. This technology helps designers to upgrade and add new features at each individual IP level without touching the entire design. It is expected that this “platform-based design” greatly reduces time, cost and overall design risk for developing derivative products, as well as providing the framework for responding quickly to future technologies and changing market requirements."

"Our newest SOC device for the digital TV market stands shoulder to shoulder with industry leaders in every core technology from picture quality, performance, data processing, speed, and specialized design architecture,” said Don H. Lee, vice president of Samsung ElectronicsSOC R&D Center. "As the adoption of digital broadcasting increases, HDTV is quickly emerging as a key product in the next-generation digital video segment.”

The US Federal Communications Commission has a determining effect on both regulations governing both American and global broadcasting and communications. The FCC has ruled that 50% of all TVs with screens 36" and larger must be equipped with tuners for digital broadcasting this year. That stipulation will be extended to all TVs with screens of 13” or larger in 2007. Currently, US broadcasters are at least 99% ready to begin digital TV broadcasts.

In 2004, France and Italy are scheduled to begin digital broadcasting, and China will join the group next year. Consumer purchases of stand-alone and built-in-HDTVs are soaring, and demand for fusion products such as the PVR is growing steadily.

Market research firm, iSuppli, puts the average annual growth rate in the digital TV at 66%, and predicts the shipment of digital TV will be increased from 17 million units in 2004 to 77 million units in 2008.

Source:www.physorg.com

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Analog - Low-power data conversion technology enhances portability

Designed to increase the portability of patient and industrial monitors and improve the performance and throughput of automated test equipment (ATE) and data acquisition systems, Analog Devices' AD7980 1-MSPS (mega-sample per second) 16-bit ADC consumes 80 percent less power and board space than the closest competing 16-bit ADC in its class.

"Power consumption is one of the dimensions of data converter performance that receives a lot of attention at ADI," said Dick Meaney, vice president of Precision Signal Processing, Analog Devices. "Offering five times lower power per conversion, combined with outstanding AC and DC linearity, the AD7980 will afford remarkable benefits to end users across many varied applications."

Increasing Patient Comfort - The small package size and reduced power consumption of the AD7980 lends it to the design of lightweight, wearable electrocardiograms (EKGs), blood pressure monitors, oxygen sensors and other medical instruments that wirelessly transmit patient information to a data centre or nurses' station. Such mobility increases patient comfort by allowing them to wear PDA-sized monitors and eliminating the need to push bulky medical equipment when moving around the hospital.

Faster and More Accurate Industrial Instruments - In industrial equipment, the fast sampling rate and low power consumption of the AD7980 allow designers to place critical components closer together to improve system performance and speed. In today's ATE systems, for example, hundreds of measurement pins are used to test each semiconductor wafer, with each pin requiring an individual ADC to reduce costly test time. The wires, switches and multiplexers used to connect the measurement pin to the measurement unit add cost, increase the risk of measurement errors and slow system response time. Also, the resulting heat dissipation is so great that data conversion must be moved from the test head to a separate mainframe. The exponentially lower power of the AD7980, relative to existing ADCs, allows designers to place the new devices adjacent to each measurement pin, simplifying the design and increasing overall system accuracy and throughput. This, in turn, reduces test time, which is a major cost component for users of ATE systems.

Improving Sensor Performance - Unlike competing devices, the power and size advantages of the AD7980 allow designers to incorporate the new ADC and a digital interface into analog sensor packages. This new breed of highly integrated 'smart sensors' eliminates the parasitic effects, signalling errors and delayed response time caused when the ADC is physically separated from the sensor using signal cables. In industrial sensing applications, this allows equipment operators to more easily and accurately measure changes in vibration, pressure and temperature that can degrade system operation.

"At National Instruments, we use ADI's PulSAR converters on a number of our core measurement and industrial I/O products," said Kurt Mandeville, principal hardware engineer at National Instruments Inc. "We see the AD7980 introduction extending PulSAR to a new level of combined high speed, low power, and small size, while preserving the performance we've come to expect from the PulSAR architecture."

The AD7980 PulSAR ADC features 7.5 mW power consumption at 1 MSPS and 75 microwatts at 10kSPS-the lowest power of any 16-bit ADC at any sample rate. Other performance enhancements include 2-LSB maximum INL and 91.5-dB signal-to-noise ratio (SNR) at 20 kHz. The AD7980 is available in LFCSP/QFN (lead-frame chip-scale package/quad flat no-lead) and MSOP (mini small-outline plastic) packages that, respectively, are five and three times smaller than any competing ADC packages. The AD7980 is pin-compatible with the AD768x MSOP family of 16-bit PulSAR ADCs, for designers looking to upgrade to a 1MSPS sample rate, and is compatible with Analog Devices' ADA4841 driver and buffer op-amps and ADR42x, ADR43x and ADR44x voltage references.

Source:www.electropages.com

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Transparent Intgrated Circuits

"This is a quantum leap in moving transparent electronics from the laboratory toward working commercial applications," said John Wager, a professor of electrical engineering at OSU. "It's proof that transparent transistors can be used to create an integrated circuit, tells us quite a bit about the speeds we may be able to achieve, and shows we can make transparent circuits with conventional photolithography techniques, the basic patterning methods used to create electronics all over the world."

Collaborators on the work at OSU include Wager; Doug Keszler, professor and head of the OSU Department of Chemistry; Janet Tate, a professor of physics; and Rick Presley, who as a master's candidate in electrical engineering at OSU has been at the cutting edge of a new electronics industry.

Transparent electronics, scientists say, may hold the key to new industries, employment opportunities, and new, more effective or less costly consumer products. Uses could range from transparent displays in the windshield of an automobile to cell phones, televisions, copiers, "smart" glass or game and toy applications. More efficient solar cells or better liquid crystal displays are possible.

Recently, OSU announced the creation of a transparent transistor based on zinc-tin-oxide. The new transparent integrated circuit is made from indium gallium oxide. Both of these compounds, which are amorphous heavy-metal cation multi-component oxides, share some virtues - they have high electron mobility, chemical stability, physical durability and ease of manufacture at low temperatures.

source:www.gizmag.com

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