Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New analog circuits could impact consumer electronics

19.02.2007
Advances in digital electronic circuits have prompted the boost in functions and ever- smaller size of such popular consumer goods as digital cameras, MP3 players and digital televisions.

But the same cannot be said of the older analog circuits in the same devices, which process natural sights and sounds in the real world. Because analog circuits haven't enjoyed a similar rate of progress, they are draining power and causing other bottlenecks in improved consumer electronic devices.

Now MIT engineers have devised new analog circuits they hope will change that. Their work was discussed this week at the International Solid State Circuits Conference (ISSCC) in San Francisco Feb. 11-15.

"During the past several decades engineers have focused on allowing signals to be processed and stored in digital forms," said Hae-Seung Lee, a professor in MIT's Microsystems Technology Laboratories (MTL) and the Department of Electrical Engineering and Computer Science (EECS). "But most real-world signals are analog signals, so analog circuits are an essential part of most electronic systems."

Analog circuits are used to amplify, process and filter analog signals and convert them to digital signals, or vice versa, so the real world and electronic devices can talk to each other. Analog signals are continuous and they vary in size, whereas digital signals have specific or discrete values.

The reason the two different types of electronic signal circuits did not advance at the same pace, Lee said, is because they are very different. Digital circuits can be decreased in size more easily, for example, by using the popular complementary metal oxide semiconductor (CMOS) technology. And much of the design and performance enhancement can actually be done by computer software rather than by a human. That's not the case with analog circuits, which Lee said require clever designs by humans to be improved because of their variable nature.

"There is a lot of room for innovation in the human design," he said. "The importance of analog circuits is growing in light of the digital improvements, so engineers can make a difference in products by working on them." Currently, analog circuits are rather expensive and they consume a disproportionate amount of power compared with digital circuits.

Another blow to analog circuits is that the advancements in fabrication (manufacturing) technology to improve digital circuits have had a negative impact on them. Traditionally, many conventional analog circuits have relied upon devices known as operational amplifiers. Two negative side effects that advanced fabrication technologies have had on operational amplifier-based analog circuits are that when used in consumer or other devices, they have reduced the range of the analog signal and decreased the device's gain. To compensate for these shortcomings, analog circuits must consume much more power, thus draining precious energy from batteries.

In addition, it still is not clear whether traditional operational amplifier-based circuits can be applied to emerging technologies such as carbon nanotube/nanowire devices and molecular devices.

Lee's research group, in collaboration with Professor Charles Sodini's group in MIT's MTL and EECS, recently demonstrated a new class of analog circuits that Lee said eliminates operational amplifiers while maintaining virtually all benefits of operational amplifier-based circuits. These new comparator-based switched capacitor (CBSC) circuits handle voltage differently than conventional analog ones, resulting in greater power efficiency.

"The new work coming out of MIT offers the intriguing possibility of eliminating operational amplifiers by proposing an architecture that relies on circuit blocks that are much more readily implemented on supply voltages of 1 volt or less," said Dave Robertson, high-speed converter product line director at Analog Devices Inc. in Norwood, Mass., and data converter subcommittee chair at ISSCC.

Lee said CBSC may enable high-performance analog circuits in emerging technologies because it would be easier to implement comparators than operational amplifiers in these technologies.

The first prototype MIT CBSC was demonstrated in an analog-to-digital converter and presented at 2006 ISSCC. The second prototype, an 8-bit, 200 MHz analog-to-digital converter, was presented at the conference this week.

Other key members of the research team are EECS graduate students John Fiorenza and Todd Sepke, who were involved in the work presented in 2006; EECS graduate student Lane Brooks, who worked on the current prototype; and Peter Holloway of National Semiconductor Corp.

The research leading to the 2006 ISSCC paper was funded by Microelectronics Advanced Research Corp. The research leading to the paper presented this week was funded by the MIT Center for Integrated Circuits and Systems and a National Defense Science and Engineering Graduate Fellowship.

Elizabeth A. Thomson | MIT News Office
Further information:
http://www.mit.edu

More articles from Power and Electrical Engineering:

nachricht Energy hybrid: Battery meets super capacitor
01.12.2016 | Technische Universität Graz

nachricht Tailor-Made Membranes for the Environment
30.11.2016 | Forschungszentrum Jülich

All articles from Power and Electrical Engineering >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

Im Focus: Molecules change shape when wet

Broadband rotational spectroscopy unravels structural reshaping of isolated molecules in the gas phase to accommodate water

In two recent publications in the Journal of Chemical Physics and in the Journal of Physical Chemistry Letters, researchers around Melanie Schnell from the Max...

Im Focus: Fraunhofer ISE Develops Highly Compact, High Frequency DC/DC Converter for Aviation

The efficiency of power electronic systems is not solely dependent on electrical efficiency but also on weight, for example, in mobile systems. When the weight of relevant components and devices in airplanes, for instance, is reduced, fuel savings can be achieved and correspondingly greenhouse gas emissions decreased. New materials and components based on gallium nitride (GaN) can help to reduce weight and increase the efficiency. With these new materials, power electronic switches can be operated at higher switching frequency, resulting in higher power density and lower material costs.

Researchers at the Fraunhofer Institute for Solar Energy Systems ISE together with partners have investigated how these materials can be used to make power...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

UTSA study describes new minimally invasive device to treat cancer and other illnesses

02.12.2016 | Medical Engineering

Plasma-zapping process could yield trans fat-free soybean oil product

02.12.2016 | Agricultural and Forestry Science

What do Netflix, Google and planetary systems have in common?

02.12.2016 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>