[Engineering Feature] Turn Down The Heat, Please!
First, you've got ICs and power semiconductors operating at higher-than-ever power rates. Now add in the rising power densities of their associated systems and power-management devices generating more heat to support higher power loads. What you wind up with is heat dissipation reaching stratospheric levels. To keep pace, thermal management must work harder to cool these systems and maintain an operating temperature that optimizes reliability—in other words, the lower...
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Sam Davis
[Technology Report] PFC And Efficiency Mandates Inspire New Power Discretes
A common element among new developments in discrete semiconductor power devices involves PFC, or power factor correction (see "Power Factor Basics," below). About 30% of the world's markets—including Europe, China, Japan, and several states in India—now require PFC in switching supplies for computing gear. Though PFC hasn't been mandated yet in the U.S., the IEEE is at work drafting standards. Stephen Oliver, who manages International Rectifier's...
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Don Tuite
[Leapfrog: First Look] MEMS: A New Power Source For Portables
Fuel cells and power generators are the newest and hottest applications for microelectromechanical-systems (MEMS) technology. Their aim is to run future portable electronic devices like CD players, digital cameras, and PDAs. The point was driven home at last month's IEEE 2005 Conference in Miami Beach, Fla., where power developments stood out among the more than 200 technical presentations. MEMS continues its progress on all fronts, refusing to rest on its steady stream...
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Roger Allan
[Design View / Design Solution] Improve Your Card Power System's Reliability
Over the last few years, the voltages in typical equipment cards have dropped dramatically—in many cases down to 1 V or lower—while the total card power continues to soar. An increase in different rail voltages also has added complexity to the power system in the form of sequencing and tracking between rails. Meanwhile, expectations for reliability and availability are rising due to the ongoing drive to reduce equipment downtime. There are several ways to meet the...
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David Cooper
[Ideas For Design] Measure Relative Humidity With A PIC MCU
A relative humidity meter can be built using a sensor with a capacitive response and a PIC microcontroller (MCU), as shown in the figure. The capacitance range of the sensor, the HS1101 from Humirel (www.humirel.com), varies from 162 to 202 pF. Functioning as an oscillator, a TLC555 CMOS timer performs the conversion from capacitance to frequency. The timer's frequency equation is given by: F = 1.44/(RA +...
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Claudia A. Angulo
, et al.
[Ideas For Design] Confidently Calculate Rectifier Input Capacitors
A rectifier input capacitor's size is often considered nebulous. Therefore, common practice is to pick a large size, and if the ripple voltage is low enough, all is okay (see the figure, a). If not, it can be increased in size. Other attempts sometimes calculate percent ripple, which I consider a largely useless term because we tend to visualize the waveform as an oscilloscope sees it—a sawtooth waveform with the limit being the...
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Jim Keith
[Ideas For Design] Derive Auxiliary Supplies From A Positive Buck DC-DC Converter
Many systems require a low-power supply in addition to the main supply. A typical example is when an analog front-end amplifier needs ±5 V, while the main digital circuitry requires +5 V only. For reasons of cost, inventory management, electromagnetic compatibility, and so on, a separate —5-V converter may not be appropriate. So, some means must be found to provide extra power rails from the main supply. Implementing a step-down IC converter's switching action may...
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Andy Fewster
[Editorial] Power Design Allows You To Act Locally, Think Globally
Welcome to a Special Issue of Electronic Design focused on power. Why? For starters, power is a universal topic for all electronic design. Beyond that, on a global scale, power is at the top of environmental and political agendas due to growing demand in the developing world. Concerns about energy consumption, global warming, and greenhouse emissions are spotlighting energy efficiency, alternative energy sources, and smart power management. Efficient public transportation and...
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Mark David
[POV: Point Of View] Making The Right MOSFET Moves
Hybrid technologies usually work well, providing they make the best of both the bipolar and MOSFET worlds, rather than magnify the worst. With this in mind, STMicroelectronics has developed a hybrid emitter-switched-bipolar transistor that the company says combines the strengths and eliminates the disadvantages of both technologies. Power bipolar technology typically is used in switching applications at frequencies below 70 kHz. Its low collector-emitter saturation...
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Paul Whytock
[POV: Point Of View] POE+: Which Road Leads To High Power Over Ethernet?
Almost as soon as the IEEE 802.3af Power-over-Ethernet standard was released, users started clamoring for more power. Thirteen watts is adequate for basic IP phones, but motorized cameras, multiradio access points, and devices with large color screens are seriously constrained. The fact that (under ideal conditions) typical CAT-5 cabling tolerates much higher current levels than the standard allows has led adventurous manufacturers to develop ad-hoc techniques to deliver extra power...
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Dave Dwelley
[Pease Porridge] What's All This Power Stuff, Anyhow?
Sometimes a lot of power is just right. Sometimes 200 hp in a car is a lot better than 100. Sometimes even 1 hp gets a bicycle up the hill quite fast. Yet a bicycle can cruise along at 6 or 8 mph with less than 0.1 hp. That's part of the elegance of the bicycle, as an extremely efficient mode of transportation. Yet by using external sources of power, I can go uphill much faster than I can by pedaling my bike. The dollars per mile can drop way down, if I count my time...
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Bob Pease
[TechView: The Industry] What Are Digital Power Supplies Worth?
The future of power supplies was one of the hot topics at the Applied Power Electronics Conference, March 6-10 in Austin, Texas. One rap session and two professional education seminars tackled the subject. While nobody offered a clear picture of what this future would be like, though, some reasonable conclusions could be drawn. For years, power supplies have been designed using analog circuit design techniques. "Digital" power supplies have been designed over the last...
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Sam Davis
[TechView: The Industry] If You Need A Formula, Just Check Your Watch
No longer do you need to fuss with looking for formulas when you're in the middle of a project and your hands are full. Instead, take a look at your wrist. TechNote Time Watch Co. offers a series of timepieces that feature key equations based on Ohm's Law. These watches and clocks come with sets of formulas printed on their faces. Two formula sets are available: one style for alternating current, and another for direct current. TechNote Time Watch recommends the ac style...
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Richard Gawel
[TechView: Analog & Power] Innovations Stack Up In Rugged Linear Motors
Linear motors, in which "forcers" propel themselves back and forth along straight guides or tracks, have a long history. Yet the ServoTube line of linear motors from Copley Controls breaks away from that history with several innovations that improve reliability and maintainability. Instead of the optical encoders most linear motors use, the ServoTube motors employ a Hall-effect position sensor, which is more rugged and doesn't require calibration. With the Hall sensor, the...
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Don Tuite
[TechView: Analog & Power] PoE Plus Study Group Sets Its Sights On 30 W
Higher limits on Power over Ethernet (PoE) are coming closer. The IEEE PoE Plus Study Group has met twice since it was formed last November to develop ways to increase the maximum power that can be transmitted via IEEE 802.3af PoE from power-source equipment (PSE) to powered devices (PDs). Currently, 802.3.af limits that to approximately 13 W at the PD. The group set a number of objectives at its first plenary session in January. It determined that the PoE Plus target...
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Don Tuite
[TechView: Analog & Power] Low-Jitter Clock Chip Puts Out 35.328 MHz
The MAX9476 generates six identical, buffered, low-voltage TTL outputs at 35.328 MHz, all synchronized with an 8-kHz input clock. Designed by Maxim Integrated Products, this clock chip targets ADSL/VDSL central-office linecards and telecom network systems. It can track the input reference within ±100 ppm. An additional low-jitter, 8-kHz clock output can be used as a reference clock for other parts of the system. This output also can automatically detect the absence of the 8-kHz...
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Don Tuite
[TechView: Communications] Multiport Ethernet Switch Embraces Full Security, IPv6 Routing, And WLAN
INCREASING DATA RATES. More VoIP phones. More wireless access point connections. These factors are putting ever-more pressure on Ethernet local-area networks (LANs). Now, Broadcom's 500 series super switch chip will enable future Ethernet switches to handle the convergence of voice, video, and data. The Broadcom StrataXGS III family's five latest members feature different port counts and functionality. The series flagship, the BCM56504,...
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Louis E. Frenzel
[TechView: Communications] Codec And SLIC Merged Into Single-Chip VoIP Solution
Voice over Internet Protocol (VoIP) is finding homes everywhere. The Le88111, a single-channel VoIP codec from Legerity, supports these applications. Yet this codec also incorporates the complete subscriber line interface circuits (SLICs) on the same chip (see the figure). As a result, it implements all BORSCHT functions associated with a common plain-old-telephone-service phone. These functions—which include battery...
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Louis E. Frenzel
[TechView: Embedded] Digital Signal Controllers Take On Power, Programming Jobs
Digital signal controllers (DSCs) are making a splash in more than one area. They're available from a number of vendors, including Analog Devices, Microchip, and Texas Instruments. They look like a mix between a digital signal processor (DSP) and a RISC processor, plus a host of microcontroller peripherals. DSCs are a hit in motor control, soft modems, multimedia support, power-supply control, and other applications. This covers a lot of ground, but embedded developers...
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William Wong
[TechView: Embedded] Development System Leads VME Line
The PowerMP4-LAB from Thales Computers combines PowerPC and Xeon processors in a small-form-factor VME rack. It supports up to four 2eSST-compatible boards. Three slots are filled with boards that handle up to four G4 1-GHz 7457 PowerPC processors. The boards also include a five-port Ethernet switch. A Fibre Channel interconnect is optional. Operating-system support includes Red Hat Linux, LynxOS, and VxWorks. The system is ready to run all software and development...
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William Wong
[TechView: Embedded] InfiniBand Invades The VME VXS Realm
SBS Technologies' 2eSST-based VXS1 VITA 41 single-board computer features a Freescale MPC7447A G4 PowerPC processor with a 4× InfiniBand host adapter and dual Gigabit Ethernet ports. The IB4X-V41 is a 24-port, VITA 41-compliant, 4× InfiniBand switch that uses a single Mellanox InfiniScale III switch chip with a 480-Gbit/s aggregate bandwidth. The IB4X-V41-AC and VXS1IB110C cost $7500 and $5800, respectively. Both are available in conduction- and convection-cooled...
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William Wong
[TechView: Embedded] VME Single-Board Computer Handles Industrial Chores
Developed by the Motorola Embedded Communications Group, the MVME3100 single-board computer (SBC) is built around Freescale's MPC8540 PowerPC MCU, which features dual Gigabit Ethernet interfaces. The board supports 320-Mbyte/s transfer via 2eSST. The Tsi148 PCI-X-to-VME bridge provides access for the dual 64-bit PMC sites. Also, the SBC can handle up to 512 Mbytes of double-data-rate error-correction-code SDRAM and 128 Mbytes of flash. Peripherals include USB 2.0, Serial ATA, and four...
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William Wong
[TechView: Embedded] Virtualize The Operating System
Need to run more than one operating system at a time? Doing so can be very handy for supporting backward compatibility. It's also a useful way to isolate new platforms while running an existing platform on the same hardware. Two approaches are available for running multiple operating systems. The first is the virtual machine manager (VMM). The second is the user-mode operating system. It's possible to mix and match these approaches, though the typical installation is much...
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William Wong
[TechView: Digital] Programmable Multicore Processor Takes On Multimedia's "Multi" Tasks
DSP applications have a new weapon in the CT3616 programmable multiprocessor engine. Developed by Cradle Technologies, it delivers an aggregate computational throughput of 24 GMACs/s for simultaneous encoding of 16 real-time MPEG-4 video channels (480 frames/s) at SIF resolution and 16 G.711 voice channels. The CT3616 also can concurrently perform complete IP packet encapsulation (RTP/UDP) thanks to an integrated 10/ 100-Mbit/s Ethernet media access controller...
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Dave Bursky
[TechView: Digital] Audio/Video Encoder Replaces Multichip Systems
Set-top boxes, personal video recorders, and surveillance systems are just some of the applications earmarked for the Cypher 7008, which boasts a complete audio and video signal-processing subsystem. Developed by WISchip International, this single chip can encode audio and video streams into most popular standard formats. Dual 166-MHz MIPS processor cores, specialized image-processing logic, and a suite of system interfaces enable the encoder to replace multiple chips in previous designs....
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Dave Bursky
[TechView: EDA] Tool Suite Paves The Path To Network-On-Chip SoCs
As system-on-a-chip (SoC) designs begin migrating down to smaller process geometries, chip sizes stay roughly the same, but their complexity increases tremendously. Signal delays due to wires predominate over gate delays. An on-chip communication crisis calls for new approaches to how IP blocks pass signals between each other. Last year, Arteris announced its plans for a network-on-chip (NoC) technology based on a globally asynchronous, locally synchronous (GALS) paradigm....
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David Maliniak
[TechView: EDA] Graphics Suite Accelerates Documentation
Document creation is key to bringing technical products to market. The design process and end users both depend on it. Now, designers can use Corel's Designer Technical Suite 12 to quickly create technical documentation and instruction and maintenance reference manuals. The suite includes key tools as well as industry-standard file compatibility. Corel Designer 12 provides new projected drawing modes to speed document creation. Corel Photo-Paint 12 is a complete...
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David Maliniak
[TechView: EDA] EDA Roundup
Support for Openaccess v2.2 has been added to Verific's HDL parsers for Verilog, SystemVerilog, and VHDL. The Open-Access interface offers a link to the Verific parsers, offering fast netlist import, along with full RTL support to the OpenAccess 2.2 database. OpenAccess is a community effort to provide interoperability among IC design tools through an open-standard applications programming interface and reference database. Verific's parsers are a key element of a path...
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David Maliniak
[TechScope] Offshore Power Generation Making Waves
It's an axiom as consistent as the ocean tides—as technology progresses, demand for power rises. Fortunately, two companies are looking at those tides to provide that power. Specifically, they're converting the mechanical energy of waves into electricity. The PowerBuoy from Ocean Power Technologies is at work off the coasts of Hawaii, New Jersey, and Spain. Measuring 5 m in diameter and 15 m long, it's submerged a meter below the ocean's surface. As it rises and falls...
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Richard Gawel
[Quick Facts] Ultracaps Kick Apps In The Pants Sponsored by: MAXWELL TECHNOLOGIES
An Electronic Power Bar Ultracapacitors, from postage-stamp-size units of a few Farads to multithousand-Farad cylinders the size of a large soda bottle, achieved affordable price points only a few years ago. Since then, they've been penetrating a range of markets in applications where batteries aren't enough. They're used wherever a quick burst of energy is needed. They also store surplus energy. Ultracaps on Circuit...
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Don Tuite
