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ELECTRONICS
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 | Electronics: Digital Multitasking (June 2008)
Appliance technology has evolved significantly over the years, and two trends are merging to fuel the next round of appliance evolution — digital motor control and digital sensor processing. Digital Signal Controllers (DSCs) are at the confluence of these trends, and they enable digital sensor processing, digital motor control and power factor correction to be implemented on a single chip.
by Steve Marsh
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 | Power: Active Efficiency (March 2008)
While most domestic appliances and office
equipment items are plugged directly into wall outlets and powered from
high-voltage alternating current (AC), nearly all of their internal circuitry
requires a low-voltage direct current (DC). Accordingly, power supplies are
required to convert AC voltage to low DC voltage. According to the research by
Ecos Consulting, roughly 3 billion AC/DC power supplies are currently used in
the U.S. and about 10 billion are used globally [1, 2].
by Hang-Seok Choi
Young-Bae Park
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 | Power: Taming the Li-ion (March 2008)
In the past, high-voltage, battery-operated
products depended upon large, heavy lead-acid type batteries to deliver the
necessary power. The size and weight of lead-acid battery packs often limited
the range of battery-operated products that could be developed. Thanks to
advances in battery technology, high-voltage battery packs can now be found in
cordless power tools, cordless home appliances, mobile medical equipment,
electric bicycles and more.
by Michael L. Coletta
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 | Power: Combined Protection (March 2008)
Metal Oxide Varistors (MOVs) are typically used
for transient over-voltage suppression in AC line voltage applications.
Lightning, inductive load switching, or capacitor bank switching may cause
transient over-voltage conditions. In these applications, there also exists the
potential for a sustained abnormal over-voltage/limited-current condition that
may cause the MOV to go into thermal runaway, resulting in overheating,
out-gassing and possibly fire.
by Philippe Di Fulvio
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 | Electronics: Memory for Micros (Jan. 2008)
Today’s 8-bit, 16-bit, and 32-bit
microcontrollers (MCUs) integrate on-chip memory such as flash memory, SRAM
(including cache), mask ROM, one-time-programmable (OTP) EPROM and electrically
erasable PROM (EEPROM) in memory sizes ranging from a few hundred bytes to several
megabytes (MB).
by Lance Zheng
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 | Electronics: The Connected Home (Jan. 2008)
In today’s highly connected world, both
businesses and consumers are coming to expect connectivity anytime, anywhere,
and on any electronic device. As a result, Ethernet connectivity is rapidly
becoming a competitive advantage, if not an absolute requirement, on a wide
variety of applications, including remote control networking, mobile
point-of-sales terminals, vending machines, security systems and medical
instrumentation, as well as networked industrial and automotive applications.
by Michelle Leyden-Li
Steve Pope
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 | Motors: Extending Efficiency (Oct. 2007)
Advanced motor-control techniques are a practical
necessity because they enable more efficient and quieter appliances. In the
past, these advanced control techniques were only available as proprietary
solutions, and hence were limited in scope to a few high-end appliances. Given
the drive toward efficient appliances running on “green” power, which is
mandated by regulations and customer preferences, these motor-control
algorithms are now being sought by designers of all classes of appliances.
Thanks to the new generation of digital-signal-controllers (DSCs), the
cost-effective implementation of advanced motor-control algorithms has become a
reality.
by Jorge Zambada
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 | Motors: Double Duty (Oct. 2007)
Advances in power and
digital control silicon technology over the past few decades have enabled a
continuous improvement in motor-drive technology. When permanent-magnet,
brushless-motor drives were first introduced to the market more than 20 years
ago, the control algorithms were implemented using a combination of analog
amplifiers and logic components. Today, highly integrated, mixed-signal
controllers enable the implementation of complex control algorithms that
maximize the efficiency of permanent-magnet AC motors.
by Aengus Murray
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 | Electronics: ZigBee Zings (Oct. 2007)
Ever since the first Internet toaster was demonstrated
at the 1990 Interop conference in San Jose, the concept of the fully connected
home — where all the major home systems and appliances talk seamlessly with
each other — has been met with a mix of amazement and amusement. While
consumers are personally more connected than ever, the various systems and
appliances in our homes remain blissful islands unto themselves, with no
effective means — or apparent need — to communicate. However, the need for
appliances to communicate is rapidly emerging, and fortunately, so are the
means with the advent of ZigBee low-cost wireless platforms.
by Bob Gohn
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 | Electronics: Using USB (Oct. 2007)
Most
everyone is familiar with USB, the Universal Serial Bus; it is an incredibly successful
technology for providing communication between personal computers and
peripherals, and there are millions of nodes in service around the world. USB
was originally designed to provide the end user with an extremely simple method
for plugging peripherals to a host, such as adding a printer to a PC. USB is
now a family of standards managed by the USB Implementers Forum. (See www.usb.org.)
by Fred Dart
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 | Electronics: Safe Charging (June 2007)
Recent
breakthroughs in nanotechnology have improved the power density and
charge/discharge rates for lithium-ion cells, thus opening up applications
requiring high power density and high charge/discharge rates. This is, of
course, in addition to the traditional battery capacities used in portable
entertainment and portable computing applications. The high-power cells are
ideal for use in power tools and other motor-driving applications, and deliver
the lithium-ion advantages and the low environmental impact (most types qualify
for disposal in the regular refuse stream).
by Alfredo H. Saab
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 | Electronics: Embedded Linux (June 2007)
By
the Spring of this year, about 20 million Linux-based mobile phone handsets had
been delivered to the market worldwide. This striking achievement occurred
despite many experts all around constantly dismissing the idea that embedded
Linux could play such a role in the market. “Linux is too big, it’s too slow
and it certainly isn’t real-time, so it can’t possibly be a realistic
solution,” they all said. But the fact is, through the efforts of the open
source Linux community and commercial Linux suppliers such as MontaVista, Linux
took the market by storm.
by Jim Ready
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 | Motors: Single-Chip Solutions (April 2007)
Electric
motors are by far the biggest consumers of energy produced in the world.
According to the Department of Energy, of the total energy produced in the
U.S., about 60 percent to 65 percent is consumed by electric motors. Among the
largest components of this are home and commercial refrigeration appliances and
HVAC systems. It is estimated that by building more efficient drives, the U.S.
can save about 25 percent in home refrigeration costs, 80 percent in HVAC costs
and about 60 percent in pump and fan control costs.
by John Pocs
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 | Motors: Efficiency Controller (April 2007)
Many
appliance motors operate inefficiently. Single-phase AC induction motors,
particularly in the fractional horsepower range, are naturally inefficient.
Furthermore, most manufacturing techniques used to improve natural motor
efficiency (iron reduction, improved lubrication to reduce friction, etc.) are
either not applicable or prohibitively expensive for these motors. For these
reasons, most of the effort in improving appliance efficiency has centered on
other areas of the system. For example, most refrigerators are able to achieve
energy reduction (and thus the coveted Energy Star rating) by improving the
seals, insulation, and airflow paths. Until very recently, little effort has
been expended on improving the efficiency of the compressor motor itself. The
same holds true for most appliances using an AC induction motor.
by John Hurst
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 | Electronics: Remote Monitoring (January 2007)
On their weekend off, a group of coworkers went to a gaming arcade to unwind. They were prepared to feed cash into a kiosk that dispensed gaming credits. Unfortunately, the machine refused to take their money. It was broken and did not have an “out-of-order” sign posted on it.
by Howard Henry Schlunder
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 | Motors: Controlling Cooling (January 2007)
Power conversion is being used in many everyday appliance products, including microwave ovens, washing machines, air conditioners and refrigerators. With many more sophisticated applications arising in conjunction with energy saving and cost reduction, more advanced control technologies like field-orientated control or load-adaptive control for motors have been developed. Performance for these advanced controls are generally unattainable via standard 8-bit microcontrollers due to lack of either signal-processing capabilities or suitable peripherals. Recently, however, this situation has changed dramatically through utilization of DSP-based controllers. The architecture of a Digital Signal Controller (DSC), which includes both digital signal processor (DSP) and microcontroller (MCU) functions with sophisticated on-chip peripherals, was designed to reduce component usage and system cost as well as advance processing power.
by Charlie Wu
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 | Motors: Driving Progress (October 2006)
Motor drives in household appliances are becoming increasingly sophisticated to meet the challenges of higher efficiency, increased reliability, and lower cost. Recent developments in the motor drives and the power components that they contain are helping to fuel this trend.
by V. Sukumar
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 | Motors: Compact Control (October 2006)
The transfer molded DIP-IPM (Dual-in-Line Intelligent Power Module) was first introduced by Mitsubishi Electric in 1998 to address the growing demand for cost-effective motor control in consumer-appliance applications.
by Eric R. Motto
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 | Electronics: Water Watcher (October 2006)
With the price of oil soaring and a worldwide debate raging over how to address the issue, it can be easy to forget that the conservation of another precious resource — water — should be top-of-mind as well.
by Juan Alvarez and Brian Reel
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 | New & Notable: Wireless Power
In the development of household devices, designers today are expected to bring new levels of convenience and flexibility to consumers. Some design limitations on achieving those goals can include traditional assumptions for connecting power and establishing communications.
by David Baarman
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 | Electronics: Sharing Solution (June 2006)
Universal Serial Bus, widely known as USB, has revolutionized PC connectivity with its hot plug-and-play simplicity. Not only has USB greatly reduced the complexity of adding peripherals to a PC, it has also fulfilled the need for a high-speed expansion port for many data-rich applications.
by Mark Fu
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 | Electronics: Protecting Parts (June 2006)
Cars, refrigerators, portable video games and submarines all have two things in common. One: Each contains electrical and electronic devices that are essential to keeping it working properly. Two: Each is exposed to a wide variety of environmental rigors that can disturb this essential, intricate electrical configuration, causing inconvenient and dangerous problems to arise.
by Kevin Brinker
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 | Electronics: Neater Networking (June 2006)
Beginning in 1990, control networks began the transformation of automation systems from direct digital controls to true networks. Unlike data networks that connect our PCs and servers, control networks connect machines (or devices) to other machines, forming automation systems for our homes, buildings and factories.
by Steve Nguyen
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 | Motors: Managing by Module (April 2006)
Today's engineers must learn to prosper in an environment that emphasizes a plug-and-play design strategy. Most major appliance manufacturers, for example, have adopted the practice of considering even critical electronic subsystems (such as a motor controller) simply as a component.
by Jeffrey Reichard and Andrew Soukup
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 | Electronics: Cool tips Hot Chips (January 2006)
Thermoelectric, graphite foam technologies target microprocessor heat.
The battle against heat in electronics is not new. IBM began using water-cooling technologies in its systems as early as the 1970s. But as semiconductor manufacturers continue to produce increasingly smaller microprocessors with greater density, both the heat and the battle against it have become more intense, demanding innovative cooling solutions. Two new technologies that are available today seek to alleviate these problems.
by Mary Lowe
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 | Electronics: Innovation with Integration (January 2006)
Putting power chips in single package simplifies design.
Integrating discrete power semiconductors, drivers, and controllers into a single package allows appliance manufacturers to simplify the design process, while ensuring a solid power electronics foundation for their products.
by Jonathan Harper
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