1124 results found, displaying items 361 - 380

Well, I never owned a toaster, but I have owned several kinds of toaster ovens. A long time ago, I had a good GE one. But then Black & Decker took over GE, and while the toaster ovens performed okay, they showed me poor reliability after a while. They would fail shortly after the warranty ran out, and I'd buy another. I soon got tired of this. They would either quit open-circuit, or the heating element would go gablooey. (That's a technical term.) Either way, they were...

Barely a year ago, most intermediate-bus architecture (IBA) implementations distributed power to point-of-load converters (POLs) at 12 V. There was some talk of using lower intermediate-bus voltages because load voltages had been shrinking, and POL switching losses increase when their output voltage is significantly less than their input voltage. Still, most IBA implementations ran at 12 V. The picture began to change six to eight months ago, and power-supply makers...

Applications subject to dirt, dust, and moisture in harsh environments can take refuge with the PSAQC60 series of 60-W power supplies. Designed by Wall Industries, these board-mounted, dual front-end devices accept input voltages from 90 to 264 V ac or 120 to 370 V dc. Output options include 5, 12, 15, or 24 V dc. Encapsulated in glass fiber, these supplies measure 4.25 by 2.24 by 1.42 in., and they're UL/cUL, TUV, CE, and CB approved. They cost $45 in OEM quantities. ...

Double-data-rate, single-data random access memory (DDR-SDRAM) has become popular in desktop and portable computing. The reason is its superior performance, low power dissipation, and competitive cost compared to other memory technologies.1 DDR initially had a 266-Mbyte/s data rate versus a 133-Mbyte/s data rate for plain SDRAM. Subsequently, the DDR data rate has increased to 400 Mbytes/s. A second-generation DDR, or DDR2, debuted at the beginning of 2004....

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It took 52 hours, 59 minutes, and 43 seconds. But the University of Michigan triumphed in the 2005 North American Solar Challenge as Momentum, its solar car, crossed the finish line last month. The course of the 10-day race took competitors on a 2500-mile route along U.S. Route 75 and the Trans-Canada Highway from Austin, Texas, to Calgary through open highways and city traffic alike. Cars from 20 university teams set out on this grueling journey, powered only by the sun....

Four dc-dc converter intellectual-property (IP) cores from LTRIM Technologies with precisely trimmed voltage references made their debut at June's Design Automation Conference in Anaheim. Previously, the company had introduced cores for three charge pumps, two low-dropout regulators, and a current regulator. In both old and new products, the laser-trimmed voltage reference is the key differentiator. To achieve resistor and transistor matching in the reference without...

Too often, designers tackle the power supply last. When that happens, the UF224 U-frame installation kit from V-Infinity makes it simple to use single-output, 2- by 2-in. board-mount dc-dc converters. There is no need to procure pc-board, metal frame, mounting hardware, and filtering and protection components. Screw terminals for input and output connections further increase the ease of installation. With the optional mounting adapter, designers can DIN rail-mount the...

What are typical charge pump applications? Charge pumps have come far in the past decade, from unregulated single-output ICs to regulated ICs with multiple output voltages. Output power and efficiency also have improved, so the charge pump can now deliver up to 250 mA at 75% efficiency (average). Most applications are in battery-based systems like cell phones, pagers, Bluetooth systems, and portable electronics. Major applications include powering white LEDs for...

In the semiconductor industry, the use of radiation-hardened power MOS devices to avoid latchup is less common than hardening logic and memories to avoid single-event upsets. Going the less-traveled path, IR introduced logic-level drive, rad-hard, n- and p-channel MOSFETs with vastly lower switching and conduction losses than bipolar power transistors, which have been the mainstay of satellite switching power supplies. Generally, spacecraft power-supply designers were stuck...

We're so used to thinking of technology migrating from military applications to the civilian world that it's surprising to find an opposite migration. Satellite communication, spread-spectrum modulation, and fly-by-wire come immediately to mind as examples of the traditional military-to-commercial pathway (see "The Latest Mil-Aero Developments," p. 52). Hence, it's a little startling to hear about chip sets expressly designed to control washing-machine motors mutating...

Decades of development and high-volume production generated mature amplifier technologies that satisfy the requirements of many market segments. Class A designs address more demanding high-end applications, while Class B and AB amplifiers serve the consumer market with cost, power, and performance tradeoffs. Class D technology, however, has changed the balance. With Class D, the power efficiency of audio amplifiers-once constrained to a range roughly between 30% and 50%-has...

Fuel Cells For The Data Center APC showed off its new Integrated Fuel Cells, which integrate into modular rack InfraStruXure data center system (Fig. 1). Between one and three of the 10-kW modules, which incorporate polymer electrolyte membrane fuel cells, can be stacked into the rack and located next to the IT equipment. Hydrogen tanks are stored outside the building. A water drain needs to be installed to...

A strong personal vision drives many of you EEs to "find a better way" to do things. When there's a market opportunity to realize that vision, you can make a huge impact. I can find no better example than Neil Rasmussen, EE and one of the founders of American Power Conversion (APC). A recent APC press day offered Rasmussen a platform for his "powerful" vision. It also showcased some great new APC technology, including fuel cells for data centers and a mobile data center in a...

What is a digital potentiometer? A conventional potentiometer or "pot" is an analog device used to vary, or control, the amount of current that flows through an electronic circuit. It's a mechanical device with a wiper that's used to select the value of the variable resistance desired. A digital potentiometer is either a volatile or nonvolatile device. The former consists of resistors or resistor arrays. It also has other electronic circuit elements like switches, logic...

Robots are already performing real work, but look for more new technologies to add more robustness. Robots conjure up images of science-fiction wonders and horrors. Though they have yet to reach the pinnacle of self-awareness and understanding, robots have been performing tasks for many years, from moving products around warehouses to vacuuming floors. Robots are practical tools today, though emerging technologies likely will move them from the backroom to the forefront. Problems...

Back when I was an executive of two major technology corporations, I was always fascinated by the strategic planning process. That's where we attempted to predict which future technologies would make an impact on us and what our new products would be two, five, and 10 years out. In the two-year timeframe, our predictions were pretty good—most big trends are relatively easy to spot. The tough part was reacting fast enough to get a piece of the action before the...

The future car is going more electric for better fuel efficiency, economy, safety, convenience, and entertainment as well as for a smoother ride. The challenge auto designers face is how to store and manage all of this electricity. Just go back 20 years to see the difference. Then, electronics primarily worked the radio, the windows, and maybe the seats—and that was it. Today, electronics have turned the car into a highly intelligent entity. Electronics...

As more biomedical equipment devices exploit ultra-low-power mixed-signal design innovations, the variety of medical semiconductor applications continues to expand. The ability to combine analog and digital signals in very close proximity alongside wireless communications has led to the development of new implantable medical devices. Implantable devices have a number of fundamental design requirements. They must feature a long and relatively maintenance-free life due to the cost...

Already playing a leading role, MEMS, nanotechnology, and robotics are rapidly marching toward more effective medical diagnostics, drug delivery, organ replacements, patient monitoring, and prosthetics. There's no question that science is destined to improve and extend the human life experience. Microelectromechanical systems (MEMS), microfluidics, nanotechnology, lab-on-a-chip devices, DSPs, implantable genetic chips, and robotics are all combining to ensure our health. The...

• Build A Smart Battery Charger Using A Single-Transistor Circuit
• Efficient DC-To-AC Inverters Charge Equipment Racks
• DC-AC inverter targets electroluminescent applications
• Easy-To-Build AC Power Meter
• Voltage-To-Current Converter Works From A Single-Supply Rail