featured product: Tektronix Handheld Real-Time

featured product: Tektronix Handheld Real-Time

Spectrum Analyzer

consumer electronics: Reducing EMI in Digital Systems wireless communications: RF Receiver Front-End Topologies for Software Radios

MRAM

The Future of Non-Volatile Memory?

portable power: Digital Power in Portable Applications/Smart Battery Management

July 2008

www.portabledesign.com

An RTC Group Publication

CEO Interview: Steve Sanghi, Microchip

contents

departments

editorial letter dave’s two cents industry news analysts’ pages product feature design idea products for designers

cover feature

MTJ Storage Element

S

N

Magnetic Layer 1 (free layer)

David Bondurant, Brad Engel and Jon Slaughter, OSC EverSpin Technologies, Inc.

wireless communications CCC/PLL

S

5 6 8 10 40 41 42

N

Magnetic Layer 2 (fixed layer)

Low Resistance

Jeffrey H. Reed, Virginia Tech

consumer electronics

Reducing EMI in Digital Systems through 28 Spread Spectrum Clock Generators

Travis Linton, Cypress Semiconductor Corp.

High Resistance

Bank 0

Bank 1

BPF

22 wireless communications

portable power

The Role of Digital Power in 32 Portable Applications

Dave Freeman, Texas Instruments

Smart Battery Management Considerations CCC 36

for Portable Applications

Ravi Pragasam, Actel Corporation

ceo interview

Steve Sanghi 48

Microchip

ADC

AGC

LNA

RX Filter

ISP AES Decryption

N

16 cover feature

RF Receiver Front-End Topologies for 22 Software Radios

S

Bank 4

N

Tunnel Barrier

MRAM—The Future of Non-Volatile Memory? 16

S

User Nonvolatile FlashROM

36 portable power

Flash Memory Blocks

Analog Quad

Analog Quad

Analog Quad

Analog Quad

ADC

Analog Quad

Analog Quad

Charge Pumps

Flash Memory Blocks

Analog Quad

Analog Quad

Bank 3

42 products for designers

JULY 2008

3

Analog Quad

Anal Qua

team editorial team

Editorial Director Editor-in-Chief Managing Editor Copy Editor

Creative Director Art Director Graphic Designer Director of Web Development Web Developer

Intern

Warren Andrews, warrena@rtcgroup.com John Donovan, johnd@rtcgroup.com Marina Tringali, marinat@rtcgroup.com Rochelle Cohn

art and media team Jason Van Dorn, jasonv@rtcgroup.com Kirsten T. Wyatt, kirstenw@rtcgroup.com Christopher Saucier, chriss@rtcgroup.com Marke Hallowell, markeh@rtcgroup.com James Wagner, jamesw@rtcgroup.com Andrew Fuller, andrewf@rtcgroup.com

management team

Associate Publisher Product Marketing Manager Western Advertising Manager Western Advertising Manager Eastern Advertising Manager Eastern Advertising Manager

Circulation

Marina Tringali, marinat@rtcgroup.com Aaron Foellmi, aaronf@rtcgroup.com Stacy Gandre, stacyg@rtcgroup.com Lauren Trudeau, laurent@rtcgroup.com Nancy Vanderslice, nancyv@rtcgroup.com Todd Milroy, toddm@rtcgroup.com Shannon McNichols, shannonm@rtcgroup.com

executive management

Chief Executive Officer Vice President Vice President of Finance Director of Corporate Marketing Director of Art and Media

John Reardon, johnr@rtcgroup.com Cindy Hickson, cindyh@rtcgroup.com Cindy Muir, cindym@rtcgroup.com Aaron Foellmi, aaronf@rtcgroup.com Jason Van Dorn, jasonv@rtcgroup.com

portable design advisory council Ravi Ambatipudi, National Semiconductor Dave Heacock, Texas Instruments Kazuyoshi Yamada, NEC America

corporate office The RTC Group 905 Calle Amanecer, Suite 250 San Clemente, CA 92673 Phone 949.226.2000 Fax 949.226.2050 www.rtcgroup.com

For reprints contact: Marina Tringali, marinat@rtcgroup.com.

Published by the RTC Group. Copyright 2008, the RTC Group. Printed in the United States. All rights reserved. All related graphics are trademarks of the RTC Group.

All other brand and product names are the property of their holders. Periodicals postage at San Clemente, CA 92673 and at additional mailing offices. Postmaster: send changes of address to: Portable Design, 905 Calle Amanecer, Suite 250, San Clemente, CA 92673. Portable Design(ISSN 1086-1300) is published monthly by RTC Group 905 Calle Amanecer, Suite 250, San Clemente, CA 92673. Telephone 949-226-2000; 949-226-2050; Web Address www.rtcgroup.com.

4

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Austin_01.indd 1

6/3/08 4:59:02 PM

editorial letter

Y

You know you’re a true tech geek when you play at what they pay you to do at work—or in my case, write about.

In Portable Design we spend a lot of time covering low-power wireless issues—from exploring evolving air interfaces to explaining how to design them into your next portable gadget. In my spare time I design and build low-power wireless transceivers that operate in the amateur radio (‘ham’) bands. Working exclusively below 30 MHz, I don’t worry whether my 5 GHz UWB signal can reach from my living room to my bedroom TV. I’m more concerned about whether Serge can hear my 5W 14 MHz signal in Tahiti or Joao in Brazil. Since local deed restrictions relegate me to using an attic dipole, that’s a neat trick.

“Daddy listens to static.” What’s that about?

In an age when cell phones have made people blasé about international wireless communications, ham radio seems like a relic—and in some ways it is. Why would you spend time analyzing sunspot cycles, atmospheric ionization and the maximum usable frequency (MUF) for wireless communication between your home and Brazil, when you can just pick up your phone can call someone there?

Cell phones are fine for point-to-point communications when you know who you’re calling.

Ham radio is fun precisely because you never know who you’ll wind up meeting. It’s a mixture of science and serendipity—like sailing. Sure, you could fire up an engine and get somewhere faster and more predictably. But as in sailing, you’re harnessing a force of nature—in this case the ionosphere—and working with it for the sheer joy of the adventure. The Germans refer to ham radio as “radio sport,” which seems a fitting term.

Still, there is a lot of science involved, and not just in analyzing propagation. Hams have long experimented with different data communications modes, inventing more than a few. I was only able to contact Serge and Joao with my tiny transmitter because I was using PSK31, a type of binary phase shift keying invented by Pete Martinez, G3PLX. PSK31 transmits 31.25 bits per second, using a binary code whose length varies with the popularity of the letter (‘e’ is two bits, ‘z’ is nine). This makes for a very efficient modulation protocol, well suited to low-power stations.

If band conditions permit, you can switch to QPSK31—quaternary phase shift keying— which adds a second BPSK carrier that is 90 degrees out of phase with the first. The second channel carries redundant bits, so QPSK adds a convolutional encoder to generate one of four

different phase shifts that correspond to patterns of five consecutive data bits. On the receiving end a Viterbi decoder sorts it all out. All of this magic is done using your computer’s sound card and Pete’s software. Plug your computer into a 5W transmitter, add a decent antenna, and you can get a lot farther than the nearest cell tower.

Hams have invented and are using a number of other interesting air interfaces. Whereas PSK31 uses anywhere from 2-12 symbols per text character, MFSK (multi-tone frequency shift keying) uses only one—but modulates an RF carrier with as many as 16 different tones; while slower than PSK31, MFSK signals are less affected by mul-

Radio Sport

john donovan, editor-in-chief tipath errors. MT-63 uses 64 different tones, plus forward error correction; MT-63 is robust against selective fading. Olivia uses a two-layer code and Walsh Functions, making it readable even when the signal is 10 dB below the noise floor (“Can you hear me now?”). JT65 is a digital protocol optimized for the extremely weak signals found in earth-moon-earth (EME) communications on the VHF bands. When not bouncing signals off the moon, hams can communicate via one of several satellites—called OSCARs (Orbiting Satellite Carrying Amateur Radio)—that support VHF and UHF communications.

Ham radio has come a long way since I got started. I got my novice license just after my 11th birthday. I got on the air using a WWII surplus BC-654 transceiver (AM and CW) that ran off a battery and dynamotor. One of my first contacts was the postmistress of Vladivostok.

I ran out and bought a world map and started sticking colored pushpins into places I worked, reading up about them in the encyclopedia at the local library. Ham radio really opened up the world for me. Now my kids can read all about Vladivostok on Wikipedia and call there on their cell phones. Still, all the instant information available on the Internet doesn’t begin to substitute for the thrill of the hunt and the unplanned meeting with a stranger.

While I enjoy experimenting with digital RF designs, I’m basically into ham radio for one reason—because it’s fun.

John Donovan, K6YLG, has been a licensed amateur radio operator for over 50 years.

When not writing for Portable Design or skulking about trade shows, he can often be found on the digital portions of the 20-, 30and 40-meter ham bands. He’s also active in the Amateur Radio Emergency Services (ARES).

JULY 2008

5

dave’s two cents

I

It is said that “Necessity is the mother of invention.” That is pretty much true as moms try to take care of their children’s needs. I think there should be another saying such as “Aggravation is the father of invention.”

For example, a friend of mine has a huge dog that appears to be a cross between a St. Bernard and a Great Dane. When this dog barks, it seems he could rattle windows down the block. As you might guess, this dog is not popular with the neighbors. After several complaints, my friend put a bark control collar on the dog. After a couple of weeks, I visited him and the dog was actually bark-

dave’s two cents on...

Hearing is Not Understanding ing quietly from behind the backyard fence. It sounded like the dog was attempting to whisper. A couple of weeks later, my friend said his neighbors were complaining again when he and his family returned from a weekend trip. The dog had figured out how to remove his collar, and after doing so chewed it into very small pieces. Apparently, the invention solved one type of aggravation only to be destroyed by another.

Recently, I was at the airport when I needed to join a conference call. I found a completely unoccupied gate and called into the conference.

About five minutes into the call, I was joined by another cell phone user. He probably needed the comfort of being close to someone. He must have thought that yelling into his phone would help the party on the other side understand him better. About three minutes later, we were joined by another cell phone user. I don’t know why in an empty gate with at least 2,000 sq ft that three callers had to be within six feet of one another. More cell phone users eventually joined us. I must have missed the sign that 6

PORTABLE DESIGN

designated this gate as a cell phone user area. I finally put my phone on mute because the other conversations interfered with the conversation on my conference call.

This aggravation started me thinking about sound processing in the cell phone. The majority of aggravating cell phone users uses wireless headsets. With a microphone on the headset and phone there should be a better way to eliminate background noise. There is certainly the in-phone processing ability. Another idea is to train users to speak quieter. From my experience, when someone has a problem understanding the other party, he speaks louder.

This may work well in the middle of nowhere, but not when you are surrounded by other phone users. It just seems to make everyone talk louder! Monk, et al, did a study on why cell phone conversations were distracting to others [1]. They found that a phone conversation at the same audio volume was much more distracting to others than a face-to-face conversation. I think it would be very interesting to do the evaluation with a room full of cell phone users.

Technology should be able to come to the aid of this aggravation. In Japan, they just do not allow cell phones to be used in confined public places. Yes, that works—and to some degree so does texting. As for my two cents, like the old dog that was taught to bark quietly, maybe humans can learn a new behavior when using a phone. With so much technology packed into a cell phone, we should be able to father an invention that provides an adaptive training program for the phone user to minimize aggravation. In the end, I guess the confusion comes from the same behavior that causes a speaker to ask, “Can you hear me?” when they really mean, “Can you understand me?” By the way, for most people your right ear is better for conversation and the left ear is better for music. So whenever I do not want to hear a complaint, I just turn my left ear to the speaker. That might even work at home.

[1] “Why are mobile phones annoying?” Monk, A.F., Carroll, J., Parker, S., Blythe, M. (2004) Behaviour and Information Technology, 23, 33-41.

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news Carbon Design Systems Acquires SoC Designer from ARM

ARM and Carbon Design Systems today announced an agreement under which Carbon will take over future development, support and sale of the SoC Designer tool.

Key members of the ARM SoC Designer development team will join Carbon Design Systems and form a new Carbon development office located in Irvine, Calif. Carbon will also gain access to ARM intellectual property (IP) in order to optimize its tools to generate cycleaccurate models of ARM processors, PrimeCell peripherals and fabric IP. This will enable ARM Partners to create cycle-accurate models of ARM IP, and provide a seamless transition for users of the SoC Designer tool to a new environment based upon models generated directly from ARM register transfer level (RTL) code.

“The ability to optimize the Carbon tool nd chain to work seamlessly with ARM’s intellectual property is a natural extension of Carbon’s er exploration ether your goal model-focused strategy,” said Rick Lucier, speak directly CEO of Carbon in a statement. “The majority ical page, the ght resource. of our customers are already using ARM IP in technology, their system-on-chip (SoC) designs. This agreees and products ment will enable Carbon to deliver a complete ed cycle-accurate tools solution to our customers, including the SoC Designer tool, enabling the generation of highly accurate models derived directly from the IP RTL code.”

Portable Design asked Bill Neifert, Carbon’s CTO and founder, why ARM would turn companies providing solutions now SoC Designer over Carbon when it’s such exploration into products, technologies and companies. Whether your goal is to research the latest datasheet fromto a company, mp to a company's technical page, the goal of Get Connected is to put you in toucha with right resource. Whichever keythedevelopment tool forlevel theof company. Acgy, Get Connected will help you connect with the companies and products you arecording searching for. to Neifert, “The number one probonnected lem that ARM faced when they sold this tool themselves was the number one problem that Carbon solves. ARM increasingly found that as they developed more and more complex processors, generating models that represented the behavior of these processors grew increasingly difficult and increasingly expensive to the point where they didn’t see themselves being able to do it profitably going forward. Carbon has the technology to generate these models directly from the RTL, so we solve the biggest problem Get Connected with companies mentioned in this article. that they had in this space. It’s just natural that www.portabledesign.com/getconnected Carbon would be a home for them.”

End of Article

8

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Get Connected with companies mentioned in this article.

ARM executives definitely see a fit. “As the leading company for system model creation, Carbon is a natural partner for the continuing support of our customers using SoC Designer and cycle-accurate models of ARM IP,” said John Cornish, vice president and general manager, ARM System Design Division. “The agreement between ARM and Carbon will ensure customers have access to a fast, cycleaccurate design environment in which they can architect and validate advanced SoC designs based on ARM IP.”

Neifert pointed out that Carbon is already installed in approximately 30% of the SoC Designer accounts that are out there right now, so they have a large mutual account base. Carbon also supports these designs and is able to generate models for them, so he predicts the transition will be smooth.

With ARM outsourcing some prime software development to an EDA company, will other EDA vendors be left out in the cold?

“The other people in the market who need these cycle-accurate models—CoWare is one example, Mentor another—they’re currently using a model from ARM,” said Neifert. “ARM will no longer supply them, so we’re working our partnership angle there in order to make sure that this modeling technology is available to them as well.”

ARM will certainly become a major focus for Carbon. Portable Design asked Neifert whether other processor vendors might start feeling neglected. Neifert declared, “Carbon is not suddenly going to become a platform company that also builds models; we will remain a modeling company that also sells the platform. And the models that we generate will

work simultaneously on every platform that we support.”

by John Donovan – Editor-in-Chief Carbon Design Systems, Acton, MA. (978) 2647300. [www.carbondesignsystems.com].

ARM Inc., Sunnyvale, CA. (408) 734-5600. [www.arm.com].

AMD Stream Processor First to Break 1 Teraflop Barrier

While you’re fine-tuning the power budget in your next portable design in MIPS/Milliwatt, it might be fun to glance upstream at what you could do if you had the firepower and a big enough battery.

At the International Supercomputing Conference, AMD introduced its next-generation stream processor, the AMD FireStream 9250, specifically designed to accelerate critical algorithms in high-performance computing (HPC), mainstream and consumer applications. The AMD FireStream 9250 breaks the one teraflop

barrier for single-precision performance. With power consumption of less than 150 watts, the AMD FireStream 9250 delivers an unprecedented rate of performance per watt efficiency with up to eight gigaflops per watt.

The AMD FireStream 9250 stream processor includes a second-generation double-precision floating point hardware implementation delivering more than 200 gigaflops, building on

the capabilities of the earlier AMD FireStream 9170, the industry’s first GP-GPU with doubleprecision floating point support.

AMD plans to deliver the FireStream 9250 and the supporting SDK in Q3 2008 at an MSRP of $999. AMD FireStream 9170, the industry’s first double-precision floating point stream processor, is currently available for purchase and is competitively priced at $1,999.

AMD, Sunnyvale, CA (408) 749-4000. [www.amd.com].

“You’re a Self-Destructive Doomsday Machine!!”

The 80s had Chainsaw Al Dunlap; the Naughties have Carl Icahn. In either case, Rule #1 is: “Try not to get their attention!” If you do, Rule #2 is: “Do not piss them off!”

That’s exactly what Yahoo’s Jerry Yang and the Yahoo board have deliberately done. Carl, of course, is a major Yahoo stockholder famous for—unlike his predecessor Chainsaw Al— taking over corporate boards at underperforming companies, firing the CEO and turning the firm around (Al preferred dismemberment).

Yahoo certainly qualifies as “underperforming,” unless you’re willing to spot them points for “doing as well as they can” against the Google juggernaut.

A lot of ink has been spilled about Microsoft’s bid for Yahoo—which Icahn strongly backs—and their subsequent rebuff(s). According to the recently unsealed complaint in a shareholder suit filed against Yahoo, when Microsoft refused to go away, Yang created a “poison pill” to ward off further Microsoft incursions, “an ingenious defense creating huge incentives for a massive employee walkout in the aftermath of a change in control. The plan gives each of Yahoo’s 14,000 full-time employees the right to quit his or her job and pocket generous termination benefits at any time during the two years following a takeover, by claiming a ‘substantive adverse alteration’ in job duties or responsibilities.”

Now that really pissed Carl off. In a letter to the SEC this week, Icahn pointed out that in its latest offer, Microsoft “had earmarked

$1.5 billion of retention incentives (representing over $100,000 per employee) meant to allay any employee concerns.” Icahn’s best line: “Until now I naively believed that self-destructive doomsday machines were fictional devices found only in James Bond movies. I never believed that anyone would actually create and activate one in real life. I guess I never knew about Yang and the Yahoo Board.”

Icahn will clearly mount a major proxy fight to take over the Yahoo board, oust Yang and cut a deal with Ballmer. That loud thud was the gauntlet hitting the floor.

by John Donovan – Editor-in-Chief

WiMAX Forum Supports European Commission Decision on Harmonization of the 2.6 GHz Frequency Band

The WiMAX Forum has announced its support of the European Commission’s regulation relating to the 2.6 GHz (2500-2690 MHz) frequency band. The 2.3, 2.6 and 3.5 GHz frequencies are key bands for Mobile WiMAX technology and will contribute to providing suitable spectrum for WiMAX consumer and business services around the world.

The 2.6 GHz decision was unanimously supported in the European Commission’s Radio Spectrum Committee, and it affords European Union administrations to make decisions in relation to the technology, services and usage that can be deployed within the band.

It also offers administrations flexibility over the balance of paired (FDD) and unpaired (TDD) spectrum that can be awarded to operators, and provides the essential technical framework. The intention is that the market can decide which technology to deploy in this band, determine the most appropriate use of this spectrum, and create significant opportunities through opening the spectrum, which will benefit all consumers.

This decision was made in addition to the recently published European Commission Decision 2008/411/EC harmonizing the 3.5 GHz band for electronic communications services and represents a key milestone in the JULY 2008

9

news portable WiMAX devices to access broadband Internet services. Currently there are more than 305 deployments of WiMAX services in 118 countries worldwide.

WiMAX Forum, Beaverton, OR. (503) 924-2922. [www.wimaxforum.org].

IEEE Approves Standard for Mobile Broadband Wireless Access

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er exploration ether your goal speak directly ical page, the ght resource. technology, es and products

drive to advance new liberalized approaches to spectrum management within the European Commission WAPECS (Wireless Access Policy for Electronic Communications Services) initiative.

With the 2.6 GHz regulations now in place, companies providing solutions now EU proceed with spectrum exploration into products, technologies and companies. Whether your goal is to research theadministrations latest datasheet fromcan a company, mp to a company's technical page, the goal of Get Connected is to put you in touchawards with the for rightthis resource.

Whichever level ofof priority. band as a matter gy, Get Connected will help you connect with the companies and products you are searching for.

The WiMAX Forum Subscriber and User onnected Forecast Study projects that growth within the region is expected to be strong, especially in Eastern Europe where cable and fixed broadband Internet is less prevalent. Europe had the second highest WiMAX user penetration by the end of 2007 and is anticipated to have the largest number of operators, followed by Asia Pacific, Af¬rica/Middle East, Americas and North America.

According to the same report, by 2012 there will be more than 133 million WiMAX users Get Connected with companies mentioned in this article. globally, and approximately 70 percent of forewww.portabledesign.com/getconnected casted WiMAX users will utilize mobile and

ed

End of Article

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Get Connected with companies mentioned in this article.

IEEE has approved a new standard for mobile broadband wireless access. IEEE Std 802.20, “Standard for Local and Metropolitan Area Networks - Standard Air Interface for Mobile Broadband Wireless Access Systems Supporting Vehicular Mobility - Physical and Media Access Control Layer Specification,” will enable the worldwide deployment of cost-effective, spectrum-efficient, ubiquitous, always-on and interoperable multi-vendor mobile broadband wireless access networks.

The standard specifies physical and medium access control layers of an air interface for interoperable mobile broadband wireless access systems, operating in licensed bands below 3.5 GHz, optimized for IP-data transport, with peak data rates per user in excess of 1 Mbit/s. It supports various vehicular mobility classes up to 250 Km/h in a Metropolitan Area Network (MAN) environment and targets spectral efficiencies, sustained user data rates and numbers of active users that are all significantly higher than achieved by existing mobile systems.

IEEE 802.20 was developed by the Mobile Broadband Wireless Access (MBWA) Working Group and sponsored by the IEEE 802 Local and Metropolitan Area Networks Standards Committee.

IEEE, New York, NY. (212) 419-7900. [www.ieee.org].

Cypress Sells MEMS Division, Retains Laser Sensor Technology

Cypress Semiconductor and Dainippon Screen Manufacturing Co. Ltd. (DNS) have announced that DNS has acquired Silicon

Light Machines (SLM), a Cypress subsidiary. The acquisition will make Silicon Light Machines a wholly owned subsidiary of DNS. Financial terms of the acquisition were not disclosed.

DNS is Silicon Light Machines’ largest Grating Light Valve (GLV) customer. GLV technology, SLM’s flagship product, consists

Untitled-4 1

of a series of microscopic ribbons suspended above a silicon substrate that can be precisely tuned to diffract laser light in different ways. The Micro-Electro-Mechanical System (MEMS) solution is ideal for computer-toplate (CTP) commercial printing and other imaging applications.

Acquired by Cypress in August 2000, SLM also developed a high-performance laser optical navigation sensor technology marketed under the name OvationONS, which has become popular in high-end gaming, and other markets.

The OvationONS product line is being integrated into Cypress’s core business.

“This transaction reflects our desire to divest businesses that are not optimally aligned with our mission to become a global programmable solutions leader,” said Cypress’s president and CEO, T.J. Rodgers in a statement.

“The divestiture of SLM’s GLV business—the

seventh such transaction in two years—will bring greater focus to our core business, while the integration of SLM’s optical laser navigation technology will enable us to expand our suite of programmable solutions serving the keyboard/mouse market.”

Cypress Semiconductor, San Jose, CA. (408) 943-2600. [www.cypress.com].

6/24/08 11:38:47 AM

JULY 2008

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analysts’ pages Mobile TV and Video to Exceed $15 Billion in Worldwide Revenue by 2012

Consumers are demanding more personalization and entertainment content on their mobile phones, driving mobile video revenue to exceed $3.5 billion in 2008, according to recent research by MultiMedia Intelligence. By 2012, the mobile video and mobile TV market will exceed $15 billion, including direct pay and advertising.

Mobile video, which relies on the mobile operator’s 3G network for delivery, has the advantage of an established network, making it the stronger of the two categories in today’s market. However, mobile TV infrastructure deployments and mobile TV handsets are rolling out aggressively, making mobile TV the dominant category in 2012.

“The mobile phone is inherently an inferior entertainment platform compared to other media devices like TVs,” according to Frank Dickson, chief research officer for MultiMedia Intelligence. “However, the mobile handset is

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er exploration ether your goal speak directly ical page, the ght resource. technology, es and products

ed

• Mobile TV ARPUs are much higher in North America and Europe than Asia due to the lack of free-to-air alternatives.

• Total Mobile TV and Video advertising revenue, including “Call to Action” advertising, will exceed $1 billion by 2012 • With the combination of a large wireless subscriber base and free-to-air alternatives, Asia has the vast majority of mobile TV subscribers. By 2012, Asia will have two thirds of all mobile TV subscribers.

Multimedia Intelligence, Phoenix, AZ. (480) 3080902. [www.multimediaintelligence.com].

WiMAX’s Appeal Threatens Both Fixed and Mobile Broadband Operators

Wireless broadband in all its forms (fixed, portable and mobile) gives operators a way to grow revenues as voice revenue growth slows, reports In-Stat. Based on survey data collected by the high-tech market research firm, WiMAX provides the right mix of features and pricing to appeal to consumers. Business users on the other hand will provide more of a challenge to WiMAX operators, primarily based on the business users need for ubiquitous coverage.

companies providing solutions now

exploration into products, technologies and companies. Whether your goal is to research the latest datasheet from a company, mp to a company's technical page, the goal of Get Connected is to put you in touch with the right resource. Whichever level of gy, Get Connected will help you connect with the companies and products you are searching for.

onnected

End of Article Get Connected

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12

inherently a superior portable communications platform. It allows for TV advertising outside the home as well as enabling new forms of advertising, including “call to action” advertising.

Call to action leverages the handset’s built-in return channel to deliver advertising beyond the capabilities of the living room TV experience.”

MultiMedia Intelligence also found that:

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Get Connected with companies mentioned in this article.

“While early WiMAX network coverage will not be as large as 3G cellular, it will be adequate to appeal to consumers,” says Daryl Schoolar, In-Stat analyst. “When respondents were presented with service examples and picked the one they most preferred, the one representing WiMAX was picked more than two-to-one over the one representing 3G cellular data. Service descriptions include informa-

tion on coverage, network performance, pricing and usage limitations.”

Recent research by In-Stat found the following: • Respondents are very interested in a wireless broadband service that will allow them to connect multiple devices under a single service plan.

• Respondents want a service that can meet both their at home and away Internet needs.

• Fixed broadband operators are vulnerable to losing subscribers to WiMAX. • Survey respondents reported increased usage of public wireless broadband between 2006 and 2007, with expectations for further increases in 2008.

In-Stat, Scottsdale, AZ. (480) 483-4440. [www.in-stat.com].

Steady Growth Seen in Worldwide 3G Mobile TV Services

3G mobile TV services may complement or compete with mobile TV broadcasting, depending on the intentions of the mobile operator, reports In-Stat. While mobile operators can rely on their own network and offer more channels via 3G mobile TV streaming services, the video quality may not be as consistent as with other forms of mobile TV technology, the hightech market research firm says.

“The 3G mobile TV service is only available to those with 3G handsets and plans, so 3G mobile TV services cannot be offered to the entire subscriber base, unlike a mobile TV broadcast service,” says Michelle Abraham.

“So, uptake in 3G mobile TV is dependent on an increase in the number of 3G subscribers.

Today 3G penetration is far less than 50% for most operators, with 3G mobile TV penetration of 3G subscribers below 10% for many mobile operators. Steady growth is expected, however, in both 3G penetration and 3G mobile TV subscriptions.”

Recent research by In-Stat found the following: • Worldwide 3G mobile TV subscribers are forecast to reach 42 million in 2012.

• 3G mobile TV subscribers grew to 6 million worldwide in 2007.

• In 2012, In-Stat expects worldwide 3G mobile TV revenues to reach $5 billion.

In-Stat, Scottsdale, AZ. (480) 483-4440. [www.in-stat.com].

The Birth of a Mobile-Handset Powerhouse

Epcos AG’s recent acquisition of NXP Semiconductor’s Radio-Frequency Microelectromechanical Systems (RF MEMS) business establishes the company as the leader in a technology that promises to expand the capabilities and cut the costs and power consumption of mobile handsets, according to iSuppli Corp.

Munich-based Epcos this year said it would take over Netherlands-based NXP’s RF MEMS business with the anticipation that it will develop into a product line worth nearly 1 billion euros. Terms of the deal were not disclosed.

RF MEMS technology can be applied to the radio-frequency front ends of mobile phones, including the antenna and the power amplifier.

Using RF MEMS, these components can be made to be tunable, meaning they can support multiple wireless interfaces—including 3G, Wi-Fi and WiMAX—and can operate over a variety of frequency bands. Such capabilities are expected to become increasingly important as mobile handsets add new features while striving to maintain small form factors, low costs and efficient power consumption.

“To support such a wide range of interfaces and bandwidths, mobile-handset makers now are employing designs that use a multitude of components for the RF front end—as many as 100 parts in some cases,” said Jérémie Bouchaud, director and principal analyst, MEMS, for iSuppli. “This represents an expensive, space-hogging and inefficient approach to RF design. Alternatively, RF MEMS can cut the component count dramatically, producing front ends that are half the cost and size and are far less complex to design. This translates into a 10 percent increase in battery time for feature-rich phones. It also provides other benefits, including superior performance, fewer dropped calls and faster data rates.”

The most promising potential use for RF MEMS switches and switched capacitors in mobile handsets is in impedance matching networks for antenna matching and matching of Power Amplifiers (PAs). The main advantage of RF MEMS switches is their capability to be integrated with other passives, combined with their high performance, especially in the areas of linearity and low insertion loss.

A Nascent Market

“While RF-MEMS hold a great deal of promise, the market remains in a developmental stage, with NXP never having commenced commercial production of such parts,” Bouchaud said. “Furthermore, Epcos presently is not a significant player in the market for mobile-handset semiconductors, although it does supply passives for wireless phones. Barriers to entry for new suppliers of components in this market are very high due to intense competition, and the large size, extensive resources and established customer relations of the established players.”

However, due to the strong promise of the technology, Epcos still is likely to find success in this area, iSuppli believes. Epcos’ strategy calls for it to eventually become a provider of complete RF subsystems, rather than a seller of discrete MEMS components. Offering more complete solutions will be key to success for Epcos.

Competing with the Wireless SemiGiants

“In the wireless-semiconductor market, demand for components increasingly is being concentrated among the Top-5 mobile-handset OEMs,” said Francis Sideco, senior analyst for wireless communications at iSuppli. “These Top-5 OEMs are purchasing platform reference designs from the semi suppliers and not discrete chips.”

While these platforms typically require expertise in both the digital and analog portions of the handset architecture, there are still some top chipset suppliers that need third-party help on the analog portion of the RF subsystem— i.e. everything in between the Power Amplifier (PA) and the antenna.

“If Epcos can field a product portfolio that JULY 2008

13

analysts’ pages iSuppli believes that within the next few years, Epcos is likely to become a leading supplier to the mobile-handset industry. iSuppli Corporation, El Segundo, CA. (310) 524-4000. [www.isuppli.com].

Semiconductor R&D Spending to Reach $49.2 Billion in 2008 differentiates it from the incumbents in the RF segment, then it will have an opportunity to partner with a baseband chipset supplier to get on its reference design,” Sideco added.

MEMS Motives?

The NXP deal represents just one step Epcos has taken on the path to MEMS leadership, iSuppli believes. Epcos has stated that MEMS

technology offers attractive growth opportunities in applications besides RF, including microphones and pressure, acceleration and rotation-rate sensors.

Epcos in February 2007 acquired Aktiv Sensor, a German MEMS pressure sensor manufacturer. Epcos also started serial production of FBAR filters in 2006, parts that belong to the RF MEMS family of devices.

Worldwide spending on semiconductor research and development grew 12% in the first quarter of 2008 to $11.1 billion compared to $10.0 billion in R&D expenditures during 1Q07, according to a new analysis of data from IC Insights’ Strategic Reviews Online database of integrated circuit suppliers. R&D spending as a percent of semiconductor market sales stood at 17.5% in 1Q08 compared to 16.4% in the same quarter last year.

In 2007, integrated device manufacturers (IDMs), fabless semiconductor companies, and

R&D Spending Among IDM, Fabless and Foundry Leaders 2007 Rank

Company

Business Model

Region

2006 R&D ($M)

2007 R&D ($M)

2007 R&D as % of Sales

% of Industry R&D in 2007

1 Intel

IDM

U.S.

5,873

5,755

35,021

16.4%

12.6%

2 Samsung

IDM

Korea

3,395

4,263

19,951

21.4%

9.3%

3 TI

IDM

U.S.

2,195

2,155

13,309

16.2%

4.7%

4 Toshiba

IDM

Japan

1,755

2,020

11,850

17.0%

4.4%

5 AMD

IDM

U.S.

1,205

1,847

6,013

30.7%

4.0%

6 STMicroelectronics

IDM

Europe

1,533

1,802

9,966

18.1%

3.9%

7 Renesas

IDM

Japan

1,350

1,360

8,001

17.0%

3.0%

8 Broadcom

Fabless

U.S.

1,117

1,349

3,754

35.9%

3.0%

9 NXP

IDM

Europe

1,248

1,344

6,026

22.3%

2.9%

Fabless

U.S.

1,220

1,215

5,619

21.6%

2.7%

11 Freescale

IDM

U.S.

1,204

1,139

5,447

20.9%

2.5%

12 Infineon**

IDM

Europe

1,011

1,067

5,772

18.5%

2.3%

13 NEC

IDM

Japan

1,138

1,043

5,593

18.6%

2.3%

14 Marvell

Fabless

U.S.

658

989

2,895

34.2%

2.2%

1 TSMC

Foundry

Taiwan

494

546

9,813

5.6%

1.2%

2 UMC

Foundry

Taiwan

284

289

3,247

8.9%

0.6%

3 Chartered

Foundry

Singapore

153

160

1,458

11.0%

0.4%

4 SMIC

Foundry

China

94

97

1,550

6.3%

0.2%

10 Qualcomm

* Semiconductor sales ** Excludes Qimonda, which was spun out of Infineon as an independent memory IC supplier.

Source: IC Insights’ Strategic Reviews Online database

14

2007 Sales* ($M)

PORTABLE DESIGN

IC Insights, Inc., Scottsdale, AZ. (480) 348-1133. [www.icinsights.com].

Flexible Display Market to Expand by Factor of 35 from 2007 to 2013

Flexible displays are playing an increasingly important role in the global high-tech industry, serving as the crucial enabling technology for a new generation of portable devices that are designed to combine mobility with compelling user interfaces.

Due to the arrival of Polymer Vision’s Readius pocket-sized e-reader and other such products, iSuppli Corp. forecasts the total flexible display market will reach $2.8 billion by 2013, a 35-times expansion from about $80 million in 2007. Rising shipments of flexible displays are being enabled by the establishment of several batch and roll-toroll manufacturing facilities. The attached figure presents iSuppli’s forecast for flexible display revenue for the period of 2007 through 2013.

“Flexible displays are intuitively appealing to end users and product designers because of their ruggedness, thinness, light weight and novelty,” said Jennifer Colegrove, Ph.D. senior analyst for emerging displays at iSuppli. “Such displays also offer manufacturers the potential for inexpensive fabrication because they can be made using new printing methods or roll-to-roll processing. Furthermore, flexible displays have the advantage of easy and relatively inexpensive shipping and safety handling compared to conventional rigid screens. When flexible displays break, they don’t have any sharp edges that can cause injuries or further damage.”

Flexible on Display at SID

Because of these attributes, flexible displays were on center stage at the Society for Information Display (SID) 2008 International Symposium, Seminar and Exhibition, held in May in Los Angeles.

South Korean manufacturer LG Display Co. Ltd. and its U.S. partner Universal Display Corp. demonstrated their 4-inch flexible Active-Matrix Organic Light-Emitting Diode (AM-OLED) at the show. The display features QVGA (320 by 240) resolution, with a metal foil backplane substrate.

E Ink showcased a variety of flexible electrophoretic bi-stable displays, from simple direct drive screens for wristwatches, to beautifully designed mobile-phone cover displays, to active matrix highresolution displays for e-book/mobile phones, such as those used in Polymer Vision’s Readius.

Polymer Vision demonstrated its soon-to-bein-the-market Readius, which features a foldable 5-inch monochrome electrophoretic display. The company also announced the color version prototype at 65k color and 127 ppi resolution.

Prime View International (PVI) demonstrated its Flexi-e, an active matrix electrophoretic

display on polyimide substrate. SiPix, Kent Displays and Bridgestone also showed a number of flexible displays.

At the SID event there also were more than a dozen presentations on flexible displays, including from Flexible Display Center at Arizona State University, Hewlett Packard, Dai Nippon Printing, Nippon Steel Corp and Honeywell.

Flex Your Power

Flexible displays are being used for a multitude of products, including e-readers/e-paper, electronic display cards, electronic shelf labels, automotive applications, clothing/wearable displays, removable storage devices and point-ofpurchase/ public signage and advertisements.

Flexible displays already entered consumers’ daily lives long before the Readius, with products like Motorola Inc.’s display for its Motofone handset, electronic card displays and t-

Global Flexible Display Revenue Forecast (in Millions of U.S. Dollars) Revenue in Millions of U.S. Dollars

pure-play wafer foundries spent a total of $45.7 billion on R&D and related engineering activities for new IC products, according to data complied by IC Insights. Industry-wide R&D expenditures grew 8% in 2007 from $42.5 billion in 2006. R&D and engineering expenditures as a percent of semiconductor sales rose to 17.9% in 2007 from 17.2% in 2006. In contrast, R&D expenditures as a percent of semiconductor revenues averaged 14.9% between 1990 and 2007.

With next-generation IC processes becoming more expensive to develop and IC design costs exploding, R&D and engineering budgets have increased at a faster rate than the industry’s sales growth since the early 1990s. R&D and engineering expenditures increased at a compound average growth rate (CAGR) of 12.7% between 1990 and 2007, while semiconductor sales grew at a CAGR of 9.9% in the 17-year period. Overall, IC Insights expects this trend to continue into the next decade, but R&D expenditures in 2008 are forecast to rise by just 8% to $49.2 billion as some IC makers attempt to curb spending and transfer some development activities to third-party foundries. Historically, pure-play foundries have invested far less of their sales in R&D as can be seen in the table.

In 1Q08, IDMs collectively spent 17.9% of revenues on R&D and related engineering activities, while fabless semiconductor suppliers averaged 25.1% of sales on R&D and engineering costs in the first quarter of 2008, according to IC Insights’ analysis. Meanwhile, pure-play silicon foundries spent only 7.1% of total sales on R&D and engineering expenditures in 1Q08, based on data from the Strategic Reviews Online database.

3000 2500 2000 1500 1000 500 0

2007 2008 2009 2010 2011 2012 2013

shirt displays. However, all the flexible displays in the market before 2008 were direct-drive or passive-matrix types. Before this year, there were no Active Matrix (AM) flexible displays that could provide the kind of image quality that users expect from their LCD-TVs and PC monitors. Because of this, 2008 represents “Year One” for the AM flexible display market.

There now are more than a dozen display technologies that can be made into flexible screens, including traditional LCD, bi-stable LCD, OLED, electrophoretic, electrochromic and Electroluminescent (EL). iSuppli Corporation, El Segundo, CA. (310) 524-4000. [www.isuppli.com].

JULY 2008

15

cover feature non-volatile memory

MRAM—The Future of NonVolatile Memory?

Does your portable wireless design need the speed of SRAM, the high density of DRAM and the non-volatility of flash in a single low-power memory? It’s time to look into MRAM.

by David Bondurant, Brad Engel and Jon Slaughter, EverSpin Technologies, Inc.

T

Today’s portable electronics have become computationally intensive devices as the user interface has migrated to a fully multimedia experience. To provide the performance required for these applications, the portable electronics designer uses multiple types of memories: a medium-speed random access memory for continuously changing data, a high-speed memory for caching instructions to the CPU, and a slower, nonvolatile memory for long-term information storage when the power is removed.

Combining all of these memory types into a single memory has been a long-standing goal of the semiconductor industry.

In the mid-1990s, research on a new type of memory based on magnetic tunnel junction (MTJ) devices began worldwide. The new memory, MRAM (Magnetoresistive Random Access Memory) used sub-micron MTJ devices integrated with standard CMOS circuitry to form a high-speed, non-volatile memory.

16

PORTABLE DESIGN

Because the data is stored as a magnetic state, MRAM is inherently nonvolatile as well as having unlimited endurance and fast operation.

The only company to date to successfully commercialize MRAM is EverSpin Technologies (recently spun-out of parent Freescale Semiconductor). MRAM has now been on the market for over two years and has proven to be a highly reliable, high-speed non-volatile memory. Unlike other non-volatile memories, MRAM has infinite cycling endurance with no programming-induced damage or wear-out. As a result of this unique property, MRAM has found wide acceptance in the battery-backed SRAM replacement market where continuous writing and long-term data retention are required and valued. Another unique property of MRAM is its ability to maintain its high performance and reliability over an extended temperature range. Current EverSpin MRAM products are available for extended temperature

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cover feature operation from -40° to 105°C and have MTJ Storage Element been demonstrated to achieve military and Magnetic Layer 1 (free layer) automotive specs from -55° to 150°C. Tunnel Barrier MRAM’s non-volMagnetic Layer 2 atility combined with (fixed layer) its high programming Low Resistance High Resistance speed and low write energy per bit proThe MTJ device has high and low resistance states corresponding to the two vides portable applistable magnetic states. cations with a unique single memory solution. Because data can be stored very quickly and is always nonvolatile, the memory can be frequently updated and then powered down, allowing the designer to optimize the balance between high performance and battery life. In addition, the MRAM process integration is compatible with standard CMOS, allowing MRAM to be easily embedded in System-on-Chip applications. This capability provides additional flexibility to the portable electronics designer.

figure 1

S

N

S

N

S

N

S

N

How MRAM Works

The heart of an MRAM memory cell is the magnetic tunnel junction (MTJ), a small device having two ferromagnetic layers separated by

figure 2 1 - Transistor, 1 - MTJ Memory Cell Free Layer i Bit line Magnetic field

Tunnel Barrier Fixed Layer

a thin dielectric layer as shown in Figure 1. It is designed to have two stable magnetic states, one with the layers polarized in the same direction and one having their magnetization directions antiparallel. The resistance of the MTJ is low if they are parallel and high if they are antiparallel. Reading an MRAM bit is very simple: a sense circuit passes a small current through the MTJ to measure if it is in the high or low resistance state.

The two major types of MRAM are different in the way they write the magnetic state.

Toggle MRAM uses magnetic fields to write while Spin-Torque MRAM uses a current pulse directly through the MTJ. The MRAM in production today is Toggle MRAM, after the robust “toggle” method of writing the bits. SpinTorque MRAM is currently in the development phase and is expected to offer improvements in density and power.

The write operation for a Toggle MRAM is accomplished by passing currents through adjacent copper lines, as shown in Figure 2, to generate the specific magnetic field pulses needed to reverse the magnetization state. Only bits at the cross-point of two write lines will receive the correct pulses to be written while other bits in the array will not change state. This write scheme is non-destructive and allows random access of any address in the array.

In Spin-Torque MRAM, the magnetic state is switched by passing a current directly through the MTJ as shown in Figure 3, rather than through the influence of magnetic fields. The spin-torque effect switches the device to the parallel state when the current is passed in one direction, and to the anti-parallel state when the current is reversed. This type of switching eliminates one of the current carrying lines, enabling a more dense architecture with a cell size comparable to DRAM.

i

MRAM Characteristics

Flux concentrating cladding layer Inlaid copper interconnects

A Toggle MRAM cell during the write operation.

18

PORTABLE DESIGN

Isolation transistor ‘off’

MRAM has a unique set of attributes, summarized in Figure 4, that allows it to replace multiple memory types in many applications.

The first three MRAM attributes result from the fundamentals of data stored as a magnetic polarization. Non-volatility is inherent because magnetization does not leak away with time like electric charge and because these small

cover feature figure 3 Spin-Torque MRAM

Since magnetic devices have a natural frequency response in the

I

GigaHertz range, fast writes are no problem and MRAM read speeds below 10 ns have been demonstrated.

magnetic devices cannot be demagnetized like large magnets. Since magnetic devices have a natural frequency response in the GigaHertz range, fast writes are no problem and MRAM read speeds below 10 ns have been demonstrated. And finally, write cycles are unlimited because there is no known wear-out mechanism related to switching a magnetic polarization.

No matter how many times the magnetic polarization is reversed it always alternates between the same two stable states.

Modular integration describes the ability to add an MRAM memory module to a technology platform without the need for any changes in standard devices or process steps for that platform. MRAM technology is modular because the magnetic devices are inserted between the metal layers of standard CMOS foundry processes with only four added mask layers. The easy integration combined with its unique attributes makes MRAM an ideal embedded memory for many advanced applications. The MRAM module can replace RAM, ROM and NVM with a single memory type that can be partitioned as needed by the application software.

The MRAM that EverSpin has in production today has proven to be the most reliable nonvolatile memory ever produced with intrinsic reliability suitable for the most demanding applications and demonstrated operation over the extended temperature range of -40ยบ to 150ยบC. This robustness is the result of the magnetic properties described previously as well as the

MTJ

Pass inherent stability of Transistor the oxide layer used in the devices.

While Toggle MRAM will continue to improve and scale to Spin Torque MRAM Cell uses current through the MTJ to switch the higher densities, Spinmagnetization direction of the free layer.

Torque MRAM is in the R&D phase with the goal of providing a significant increase in density, lower cost, and lower power. The spin-torque effect begins to be practical for dimensions below 100 nm, and the required current decreases as the area of the bit decreases. This and other factors make 65 nm the approximate entry point for SpinTorque MRAM with smaller technology nodes becoming increasingly attractive.

Operating Spin-Torque MRAM arrays and reliable spin-torque switching have already been demonstrated. For example, EverSpin has demonstrated 65 nm-scale bits cycled to an equivalent of over 1012 cycles without degradation of the bit parameters (Figure 5). While a number of challenges remain to be overcome before this type of MRAM will be ready for production, the results to date indicate that this technology could challenge all memory types at future lithography nodes.

Advantages for Portable Applications

The current EverSpin 1, 2 and 4 Mbit MRAM products have been designed for high JULY 2008

19

cover feature

figure 4

Nonvolatile

Data Retention - ≥ 20 years

Fast

Symmetrical Read/Write - 35ns

Unlimited Cycling

Unlimited Endurance - ≥ 1016

Modular Integration

Easily Integrates in Back End Compatible with Embedded Designs

Extended Temperatures

-40 °C < T < 150 °C Operation Demonstrated

Highly Reliable

Intrinsic Reliability Exceeds 20 Year Lifetime at 150 °C Continuous Use

MRAM has a unique set of memory characteristics that allow it to replace multiple memory types.

table 1

MRAM (180 nm)

MRAM (65nm)

SpinTorque MRAM (65 nm)

Cell Size (um2)

1.25

0.16

0.04

Read Time

35 ns

10 ns

10 ns

10 - 50 ns

10 ns

1 ns

Flash (65 nm)

DRAM (65 nm)

SRAM (65 nm)

0.04

0.03

0.3

Program Time

5 ns

5 ns

10 ns

0.1-100 ms

10 ns

1 ns

Program Energy/bit

150 pJ

100 pJ

1 pJ

10,000 pJ

5 pJ

5 pJ

Endurance

> 1015

> 1015

>1015

105 write

>1015

>1015

Non-volatility

YES

YES

YES

YES

NO

NO

Comparison of Advanced Memories

20

PORTABLE DESIGN

performance with 35 ns read/write cycle time and SRAM interface timing. Typical linepowered applications include computer storage systems & servers, industrial automation & robotic, energy management, transportation and military/avionics systems. However, a number of applications take advantage of MRAM’s ability to rapidly cycle power to provide zero power standby current. One current MRAM wireless application is a wireless battery-powered sensor that is periodically powered up to take measurements and then powered down into an ultra-low standby current state with MRAM powered-off. Other examples are contactless RFID tag devices for factory automation and transportation that are powered from an RF field with the MRAM off between transactions.

We expect MRAM applications in batterypowered and wireless applications to increase significantly as the first serial SPI MRAM products reach the market next year. The products are compatible with industry standard serial EEPROM, flash and FRAM products, but offer sleep mode standby currents as low as 3 uA, high serial clock rates, no write delays, unlimited endurance and superior high-temperature data retention. These products will be directly compatible with most ultra-low-power MCU products.

The modular nature of MRAM makes it easily embedded for replacement of both embedded flash and SRAM with a single memory type. It integrates with CMOS logic processes with much less process complexity than either embedded flash or DRAM, and is added at the end of the process to minimize impact on underlying mixed signal circuits.

Looking farther into the future, successful development of Spin-Torque MRAM technology would enable density and price points comparable to NOR flash and low-power DRAM. Portable systems would benefit by the ability of Spin-Torque MRAM to provide DRAM read/write speed, unlimited endurance, low active current and standby current, and the zero power down current, while operating at a native 1.2-volt power supply level without charge pumps. Such a stand-alone memory would reduce system chip count while increasing software flexibility to parti-

cover feature figure 5

Wireless and portable applications will 1200

fast speed of SRAM, high density of DRAM and the non-volatility of flash in a single lowpower memory.

Resistance (Ω)

benefit from a memory that combines the

1100 1000 900 800

tion memory as either data or program storage dynamically. Embedded Spin-Torque MRAM would improve system operation by reducing leakage currents, simplifying block power down, and improving system flexibility to partition programs and data dynamically.

Competitive Landscape and Outlook

Today’s low-power DRAM, NOR flash and flash technologies are encountering increasingly difficult challenges as processes are scaled to 45 nm and below. A number of new memory technologies are competing to replace the incumbent commodity memory technologies.

Ferroelectric RAM and Phase Change Memory technologies have been proposed as the replacements for wireless applications, but have faced limitations in read/write speed, write endurance and long-term data retention. Because of the proven manufacturability and high-reliability of MRAM, Spin-Torque MRAM has emerged as a more attractive alternative for advanced nodes. Spin-Torque MRAM has the potential to provide the superior speed, unlimited endurance and long-term data retention that the market needs, along with high density, low cost and low power. It is competitive with both DRAM and NOR flash cell size at 65 nm while providing lower write power than DRAM or SRAM.

101

102

103

104

105

speed of SRAM, high Pulse number density of DRAM and the non-volatility of ST MRAM Endurance not degraded by cycling. flash in a single lowpower memory that could simplify both chipset and stand-alone memory hierarchies.

A number of technologies are competing to fill this need. With MRAM in production and Spin-Torque MRAM in development, this integrated magnetic technology is one of the leading candidates to replace DRAM and flash in wireless systems.

Current MRAM products demonstrate a uniquely useful set of attributes—fast read/ write speed, unlimited endurance, long-term data retention without power, and zero power standby current with power off. MRAM is currently being used in select wireless applications, and the first chips with embedded MRAM are expected to enter the market soon.

Intensive R&D efforts are focused on SpinTorque MRAM with the goal of achieving density comparable to DRAM and NOR flash but with lower write power and all the other advantages of MRAM.

106

EverSpin Technologies, Inc., Chandler, AZ. (719) 661-7889. [www.everspin.com].

Conclusions

Wireless and portable applications will benefit from a memory that combines the fast JULY 2008

21

wireless communications software radio

RF Receiver FrontEnd Topologies for Software Radios A number of different RF front-end topologies are appropriate for software radios, each with its own advantages and disadvantages. This article explores the trade-offs involved with each approach.

by Jeffrey H. Reed, Virginia Tech

T

The most common types of RF front-ends for software radios are dual conversion, single conversion and tuned radio frequency receivers. The suitability of a particular receiver topology depends on a number of parameters that may include the following: • Sensitivity defines the weakest signal level that a receiver can detect and is usually determined by the various noise sources in the receiver.

• Selectivity represents the ability of the receiver to detect the desired signal and reject all others.

• Stability indicates the lack of change in the receiver gain and operating frequency with temperature, time, voltage, etc.

• Dynamic range is the difference in power between the weakest signal that the receiver can detect and the strongest signal that can be supported (either in-band or out-of- band) on the receiver without detrimental effects.

22

PORTABLE DESIGN

• Spurious response is a receiver’s freedom from interference due to internally generated spurious signals or to their interaction with external signals.

Topologies Tuned RF The tuned radio frequency (TRF) receiver, shown in Figure 1, consists of an antenna connected to an RF bandpass filter (BPF). The BPF selects the signal and the LNA with the automatic gain control (AGC) raises the signal level for compatibility with the ADC. This BPF bandwidth relative to the carrier frequency can be quite narrow, while in absolute bandwidth, it may be quite broad. For example, a second-order inductor and capacitor filter would require a filter quality factor of 107 to extract a 30 kHz signal at 900 MHz with 60 dB of attenuation for a channel 60 kHz away, which is highly impractical.

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The primary difficulty in creating a practical TRF receiver is the limitation of the ADC, which must handle high-frequency signals. In addition, given the bandwidth and roll-off limitations of the RF filter, the sampling rate of the ADC must be very high to avoid significant aliasing. High power consumption is inevitable with high sampling rate conversion. The ADC must accommodate multiple signals over the wide bandwidth of the RF filter (potentially tens of megahertz or more) with high dynamic figure 1 range of approximately 100 dB. Achieving this sampling characteristic is difficult, Binary expensive and powerOutput intensive, and extreme ADC AGC BPF LNA demands are made of the tunable RF filter RX Filter to remove interference signals that consume the dynamic range of TRF Digital Signal Processing Receiver the ADC. Non-idealities of the ADC, such figure 2 as jitter and finite aperture size, lead to dis(a) tortion of the signal.

Baseband In practice, the RF Digital Output filter can select only a AGC BPF BPF ADC LNA LPF general band of interRX Filter RX Filter est: subsequent filtering within the DSP LO is required to extract the desired chanÂŹnel.

The AGC adjusts its (b) gain to accommodate I varying signal levels LPF ADC to utilize the full range of the ADC without LO overloading it. HowBaseband BPF BPF AGC ever, the especially LNA Digital 900 Output high gain required for RX Filter RX Filter a single-stage AGC in this application may LPF ADC be difficult to conQ trol. Nevertheless, the advantage of this ap(a) Single-conversion receiver for binary phase-shift keying (BFSK) and proach is the minimal amplitude modulation (AM); (b) single-conversion for frequency- and phasenumber of analog parts modulated signals. required.

24

PORTABLE DESIGN

Single Conversion A very popular topology for low-power application is the single conversion receiver (also known as homodyne, direct conversion, or zeroIF receiver), which uses a single mixing stage to convert the signal to baseband or near baseband.

This receiver architecture, shown in Figure 2, has one stage of downconversion. In the case of a phase or frequency-modulated signal, I&Q downconversion is required since the upper and lower sidebands of these signals contain different information and the sidebands would overlap for a real downconversion. Mixers tend to have high power consumption, and since only one mixer stage (possibly I&Q) is used in the single conversion receiver, the receiver potentially offers good power consumption characteristics.

Typically, improved power consumption at the mixer can be traded for dynamic range.

LO leakage has the potential of creating leakage across input ports, causing the mixer to downconvert a received version of itself (selfmixing), which may result in a large DC bias at the mixer output. Isolation between the LO and input to the mixer or other components is very desirable but difficult to achieve. An alternating current (AC) coupling capacitor helps but may remove important DC information in the signal. A more effective though more costly approach is to track the DC error after digitization and feed back a correcting bias signal using a DAC and subtracter.

A non-ideal I&Q downconversion may result if the phase and amplitude of the branches are not matched and cause a warping of the received signal constellation diagram, as shown in Figure 3, for the case of a quadrature phaseshift keying (QPSK) signal. Furthermore, the phase stability on the local oscillator is extreme given the high and precise frequency needed to convert the signal to baseband since phase noise falls within the baseband. Good circuit design with digital signal processing based compensation can help mitigate these problems. Note that these problems are absent when using the TRF receiver.

Dual Conversion In some cases, rather than directly downconverting the signal to baseband, it may be more convenient to downconvert to some low

wireless communications

intermediate frequency at which the signal may be digitized and downconverted by subsequent digital signal processing operations. A more complex LPF with better roll-off characteristics can help reduce out-of-band interfer¬ence and thus lessen the dynamic range requirement of the ADC, but it could also allow more noise to enter the system (less sensitivity) resulting in non-linear distortion products from the filter.

The most common RF front-end for radios is the heterodyne receiver. This receiver, shown in Figure 4a, is commonly used in analog radios. A heterodyne receiver works by frequency translating the incoming signal to an IF that is fixed and independent of the de¬sired signal’s center frequency. When this IF frequency is lower than the center frequency of the received signal’s carrier frequency and higher than the bandwidth of the desired signal, the receiver is called a superheterodyne receiver. The desired signal that is now frequency translated to a fixed IF can be more easily filtered, amplified and demodulated.

Plenty of good quality RF components are available for standard IF frequencies.

Often a superheterodyne receiver involves using two stages of downconversion. Such a dual con¬version receiver has the advantage of relaxed filtering requirements. Because the filtering occurs in stages, the filtering requirements at each stage can be more relaxed than in a sin¬gle conversion receiver. That is, by lowering the center frequency of the signal using the first stage of downconversion, the filter quality factor can also be relaxed because the ratio of center frequency to filter bandwidth is reduced.

Gain can also be achieved in stages, reducing the LO power on the mixers and relaxing the isolation needed between the LOs and the mixer inputs. The distribution of this gain throughout the front-end impacts the overall dynamic range. DC offset is of no concern in this architecture since the LO frequency ωlo is not equal to the center frequency of the desired signal at the input of the mixer. The additional mixer and LO result in higher power consumption and a larger circuit than that of a single conversion receiver, and often the second filter can be expensive and may exist off-chip. The characteristics of the I&Q mixers need to be matched to prevent distortion like that shown in Figure 3. Phase noise also impacts overall

performance by causing unintended modulation on the desired signal because of the timevarying frequency of the non-ideal LO. At each mixer stage, not only is the signal downconverted, but also a portion of the band at ωI, the image frequency, is upconverted, which places it on top of the frequency translated desired signal. For instance, a 68 MHz LO (ωlo) will downconvert the desired signal by 68 MHz, but the adjacent band, located 136 MHz below the desired signal, will be upconverted to the same frequency range (ωIF, the interfigure 3 mediate frequency) in which the desired Symbol states without noise signal now lies. This Symbol states problem is illustrated with noise in Figure 5.

Q Q To mitigate this selfinduced interference, an image filter precedes the mixer to suppress the low-frequency band that might interfere I with the desired signal after the mixing operation. A consider¬ation in choosing the LO frequency is ensuring standard filters can be (b). DC Bias due to Self-Mixing. (a). Ideal QPSK Constellation DC is present in both I&Q. utilized after the mixer.

Designing the image filQ Q ter becomes especially challenging if the band of potential interference is heavily occupied with high-power signals. In general, trade-offs exist I in the selection of the IF frequency, the image filter and the post-mixer filter. In some situations, it makes sense to (c). Gain Mismatch. (d). Phase Mismatch. use an LO frequency Q is amplified more than I. The phase between I&Q that is higher than that branches is not 90°, and amplitude is distorted. of the desired signal to up-convert the negative frequency image of the Impact on constellation due to imperfect mixing process. (Note that with desired signal to a posinoise and distortion, a symbol is more likely to lie in the wrong quadrant, tive IF frequency if this leading to a bit error.) reduces interference JULY 2008

25

I

I

wireless communications

nd

from the image. Other approaches to mitigating the image problem are using I&Q downconversion, such as the Weaver or Hartley mixing process, and using mixer structures that use I&Q conversion and phasing to reject the image.

figure 4 (a) IF Binary Output BPF

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receiver, except for the use of a BPF after the first mixer.) (b) Dual-conversion er exploration superheterodyne receiver. ether your goal speak directly ical page, the ght resource. figure 5 technology, es and products

Which Is Best?

The designer needs to weigh the multitude of combinations before arriving at the optimal design, and, generally, a trade-off occurs between sensitivity and selectivity.

Higher-order conversion receivers (with multiple downconversion stages) may be the best solution in some situ¬ations, but more mixers may mean more spurious signals, particularly when high-power signals are present.

ed Desired Signal

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The image problemin of receivers. (Note the LO frequency is 68 MHz.) www.portabledesign.com/getconnected

26

PORTABLE DESIGN

Get Connected with companies mentioned in this article.

This article is excerpted from Reed, Jeffrey H., ed. Software Radio: A Modern Engineering Approach. New Jersey: Prentice Hall, 2002. Used with permission.

About the Author

Amplitude

Adjacent Channel Interference

The TRF receiver is better suited for a software radio that supports multiple air-interface modes and multiple bands than the single conversion receiver, and particularly better than the het¬erodyne receiver because the filter requirements for the IF stages make it difficult to support the multiple bandwidths that might be required of a multimode receiver. Retuning a receiver can result in a complex interaction of multiple components comprising the RF chain.

The simpler the RF chain, the more predictable its response will be after retuning. The choice of a single or double conversion receiver depends on a number of factors including chan¬nel spacing, frequency plan, spurious response and total gain. In general, the smaller the channel spacing, the more attractive the double conversion receiver becomes because of its ability to narrowly filter the desired signal.

Dr. Jeffrey H. Reed is a professor in the Bradley Department of Electrical and Com¬puter Engineering at Virginia Polytechnic Institute and State University (Virginia Tech) in Blacksburg, Virginia. He currently serves as Director of the Mobile and Portable Radio Research Group (MPRG). Dr. Reed received his B.S., M.S. and Ph.D. from the Univer¬sity of California, Davis (UC Davis), in 1979-1987. Dr. Reed was employed by Signal Science, Inc. from 1980 to 1986 and worked as a private consultant and part-time faculty member at UC Davis before coining to Virginia Tech in 1992.

Dr. Reed’s areas of expertise are DSP implementation and software radios. He has coauthored or co-edited fourteen books and over ninety-eight journal and conference papers. Dr. Reed is a past recipient of Virginia Tech’s College of Engineering Award for Excellence in Research. He has served as principal investigator or co-principal investigator on over fortyfour projects while at Virginia Tech. Dr. Reed continues to work as a consultant and has provided short courses to many companies.

portabledesign conference & exhibition Power Management for a Wireless World Conference sessions, Analyst Presentations and Panel Discussions on designing and powering portable, low-power wireless consumer devices.

Complimentary Registration Keynotes Panel Discussions Technical Seminars Exhibition Lunch Networking Reception

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consumer electronics EMI reduction

Reducing EMI in Digital Systems through Spread Spectrum Clock Generators High-speed data = high-speed clocks = EMI. It doesnâ&#x20AC;&#x2122;t have to be that way.

by Travis Linton, Product Marketing Manager, Cypress Semiconductor Corp.

A

Any device capable of generating signals with frequencies in the RF range is a potential source of Electro-Magnetic Interference (EMI). These signals can cause interference in the normal operation of electronic devices such as radios, televisions, cell phones and other types of equipment. The primary sources of EMI in most systems are the clock generation and distribution circuits.

Interference is caused by electro-magnetic waves that are produced by charged particles moving in an electric field. This condition occurs wherever electric signals exist. There are regulatory agencies that require devices that produce EMI to adhere to a certain set of rules and regulations. Among these rules and regulations is a requirement that the source of radiation not be greater than a pre-determined level at a certain distance from the source within a fixed frequency range. In the United States, the regulatory agency that governs the control of

28

PORTABLE DESIGN

EMI is the Federal Communications Commission (FCC).

Causes of EMI

Clock sources can contribute to EMI in two ways. EMI can be produced through the repetitive nature of a synchronous clock and from an improperly terminated trace. The energy from the clocks radiates into a field through an antenna. An antenna might be in the form of PCB traces, PCB rework wires, components with insufficient shielding, connectors, cables (shielded or unshielded), or improperly grounded equipment.

In high-speed digital devices, fixed frequency clocks are the primary source of EMI because they are always operating at a constant frequency that allows energy to increase to higher levels. Signals that are non-repetitive or asynchronous will not generate as much EMI. As the need for higher throughput has driven

faster clock frequencies, signal transition rates have also increased. But with the faster rise and fall times comes an even larger increase in the energy level of the radiated signal. Figure 1 shows two signals that have the same frequency, amplitude, duty cycle and phase. However, they differ in the signal transition rate. The clock with the faster rise time will have a measurably higher amount of radiated energy than the slower transitioning signal.

The second factor that contributes to EMI is an improperly terminated trace. A trace can exhibit overshoot and undershoot when there is an impedance mismatch. When this condition occurs, radiated energy will increase. Depending on the severity of the overshoot and undershoot levels, this could represent as much as 3 to 4 dB of EMI at a particular signal, or node in EMI terms. If there are ten to twenty nodes with severe overshoot, then passing the FCC compliance test is in jeopardy.

Reducing EMI

There are several methods with which to solve an EMI problem in a digital system. The designer could choose to shield the design, filter a signal, or remove the energy from the offending source. These methods could be used individually or in conjunction with others.

The first method, shielding, is not an electrical solution but a mechanical implementation.

Shielding uses metallic packaging to keep the EMI from escaping the unit. This method has been used often in the past but it can sometimes be a costly solution. It also doesnâ&#x20AC;&#x2122;t lend itself to an easy fix when an EMI problem is found shortly before a product release.

The remaining methods, filtering and energy removal, isolate the trace that is radiating the EMI. To identify which trace (or traces) is causing the problem, a test in the anechoic chamber or an EMI simulation should be performed. From this testing, an emission report will identify which frequencies exceed the specified limits. These particular frequencies are typically called hot spots. By knowing the frequencies (including the harmonics) the clock trace can be identified.

Since poorly terminated signals can cause hot spots, the first solution is to ensure all sig-

nals are properly terminated. The signals that are causing the EMI should be simulated and the traces should be analyzed for overshoot and undershoot. If there are exceptional amounts, then adjust the termination values to create figure 1 a better waveform.

If all the signals are properly terminated and little to no overshoot is present, then the transition rate of the clock needs to be addressed. A substitution of a slower speed buffer may supply the answer. Many clock buffers have an option 5.0 ns/DIV for high-speed or lowspeed outputs. Often, these parts are either Slower transition rates reduce EMI. pin-for-pin replacements or the device has a programmable slew rate. If the lower drive is acceptable for the system, this may be the best solution. This method directly addresses the clock trace that is causing the problem and typically there is no additional cost to implement.

If a slower device is not available, filtering is a common way to slow the edge rate of a signal.

This usually involves adding a capacitor to the signal that will soften the edge rate based on an RC time constant. The values of the capacitors generally range from 5 to 15 pF. Often designers will include these capacitors, which need to be placed near the source, in their schematics but not populate them unless an EMI problem is exposed. If the clock trace uses series termination, the capacitor can be placed on either side of the resistor to reduce EMI. However, for optimal termination and signal integrity, the capacitor needs to be placed between the driver and the resistor.

Although this method reduces EMI, it does, however, degrade the signal integrity of the clock. Instead of sharp, clean edges suitable for high-speed clocks, the edges become rounded.

Also, capacitors may need to be added for every clock copy in the design.

JULY 2008

29

consumer electronics

Another method to address signals that emit excessive radiation is clock modulation. Clock modulation, also known as Spread Spectrum, has been used effectively in virtually all PCs for many years, and is ideally suited to many other applications as well. Spread spectrum

This is the variable that is fine-tuned to bring EMI within spec.

The shape of the modulation profile is important in producing the maximum amount of db reduction. Although a triangle wave profile is simple to implement and gives good results, the Lexmark profile

figure 2

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clocking (SSC) is an efficient, effective and less costly alternative method for controlling EMI. SSC reduces EMI peaks by spreading the energy from a clock across a wider frequency band. Figure 2 shows that as the frecompanies providing solutions now quency is made wider, the energy peak exploration into products, technologies and companies. Whether your goal is to research the latestband datasheet from a company, mp to a company's technical page, the goal of Get Connected is to put you in touchiswith the right resource. Whichever level of reduced. gy, Get Connected will help you connect with the companies and products you are searching With for. this technique, peak reductions of onnected 5 dB to 18 dB are possible. It can be implemented with few or no additional components, and has the advantage that energy spreading is maintained as clock signals are fanned out and propagated to their destinations.

Plotting the clock frequency versus time, we see the shape of the modulation signal.

The maximum frequency excursion, Î&#x201D;f, is the difference between the upper and lower limits. This is usually specified as a percentage of the main frequency, and is normally Get Connected with companies mentioned in this article. referred to as the spread amount. Typical www.portabledesign.com/getconnected spread values are between 0.25% and 4%.

End of Article

30

PORTABLE DESIGN

Get Connected with companies mentioned in this article.

alternative method for controlling EMI.

(Figure 3) is optimized to produce a flatter frequency profile, as seen in Figure 2, and greater peak reduction. Most SSC devices use either one profile or the other, though some devices may have a selectable or programmable profile.

Modulation Rate

The last variable of the modulation signal is the frequency. A standard modulation frequency is approximately 30 kHz. In general, a low modulation frequency is desirable because it minimizes many possible negative effects that a spread spectrum clock may have on down-stream devices. If the modulation frequency is too low, however, audio interference becomes a risk. This is why 30 kHz is chosenâ&#x20AC;&#x201D;it is comfortably clear of the audio band. Occasionally modulation frequencies up to 100 kHz or more are seen, but these are usually specific applications that are known to be compatible with these modulation frequencies. Most SSC devices operate at a fixed modulation frequency.

Cost Savings with EMI Suppression

Use of an EMI suppression-enabled clock IC can result in a reduction of system radiated EMI of 10 dB of more. This can result in dramatic cost savings for the system, of anywhere from less than $1, to $5-10 or more. Conventional techniques for reducing EMI include shielding ground planes, filtering components and shielding. Going from a two-layer board to a four-layer board to insert additional ground planes could easily cost $56. Filtering EMI typically uses ~$.25 worth of resistors, inductors and capacitors, and often $.70 worth of common mode chokes and toroids. In many cases filtering will not be enough to allow a system to pass EMI tests, in

consumer electronics

The amount of EMI reduction depends not only on the amount of spread, but also on the clock frequency. For example, a 1% spread on a 100 MHz clock means that the peak-to-peak frequency excursion is 1 MHz. In comparison, a 1% spread on a 20 MHz clock is only 200 kHz. So while the spread percentage is the same for these two cases, the actual frequency spread is not and therefore the EMI peak reduction is also not the same. A lower frequency clock requires a greater spread percentage to achieve the same EMI reduction as a higher frequency clock.

This relationship to frequency applies to the harmonics as well as to the main frequency. Just as a harmonic is an integer multiple of the main frequency, the width of frequency spreading is similarly multiplied. Going back to our 100 MHz clock with 1% spread, the third harmonic is at 300 MHz and has 3 MHz of spreadâ&#x20AC;&#x201D;three times the spread on the 100 MHz clock. Because of this increased frequency spread for the harmonic, the EMI reduction is correspondingly greater compared to the main frequency.

One more interesting observation is that the relationship between peak EMI reduction and spread amount is non-linear. The most optimum reduction is achieved with a small spread percentage, since increasing the percentage yields diminishing returns. This is one reason why few applications use more than 5% of spread.

which case costly shielding may be required.

Shielding can easily add several dollars to the cost of a system.

Integrating Provisions for EMI

When it comes time to integrate SSC into a figure 3 design, engineers will find there are a variety fnom of SSC devices. Clock generators produce a specified frequency from a crystal. Some of them can generate a combination of spread spectrum clocks and non-spread clocks, at multiple unrelated frequencies. Single fre(1-δ)fnom quency, fully integrat1/fm ed spread-spectrum oscillators (SSXO) are also available. Other The Lexmark profile produces a flatter frequency profile and greater peak low pin-count devices reduction than a simple triangle wave. can be placed in the path of an ordinary clock signal to add spread spectrum.

Many SSC devices allow spread to be turned on or off, and some allow the amount of spread to be adjusted by pin selection. Programmable spread spectrum clock generators provide considerable flexibility, allowing the user to specify both the output frequency and the exact amount of spread. Output drive strength is also configurable on most programmables. If EMI testing at the end of the design cycle determines that a change to the spread parameters is needed, a field programmer can be used to quickly program a device with the new settings. In this way, by provisioning for SSC during the design of a system, an engineer can rest assured that full provisions are in place to control clock-generated EMI, and that only a small amount of time needs to be budgeted for EMI fine tuning at the end of the design cycle.

Cypress Semiconductor, San Jose, CA. (408) 943-2600. [www.cypress.com].

JULY 2008

31

portable power battery management

The Role of Digital Power in Portable Applications By minimizing the high-speed circuit components and taking advantage of smaller process geometries, digital power solutions have become practical for portable appliances.

by Dave Freeman, Engineering Manager, System Power Products, Texas Instruments

P

Power management is vital to extending runtime for portable applications. Power conversion in these applications has been dominated by analog circuits, while the power management has been performed by embedded processors and simple sequencers. These analog solutions have served the system well. With recent trends in power solutions focusing on digital control, new opportunities emerge for portable power solutions.

This article presents digital power solutions for portable applications that take advantage of digital powerâ&#x20AC;&#x2122;s combination of management and control. When management and control are separated, the interfaces between these circuits limit flexibility and the level of complexity that can be addressed. Digital power solutions integrate these functions and are capable of addressing much higher levels of complexity.

Portable applications have many operational modes. Digital power solutions allow each

32

PORTABLE DESIGN

mode to be powered uniquely and, therefore, optimized for best performance. Examples include adaptive compensation and phase management in portable applications.

Digital Aspects of Portable Applications

The developments in deep sub-micron processes have greatly benefited portable applications such as multimedia cell phones and notebook computing. However, these smaller geometries come with their challenges. Power has become a major issue.

There are very effective solutions to decreasing leakage current and methods for improving performance without increasing the required power. As shown in Figure 1, power management can provide nearly an order of magnitude reduction in quiescent current. This standby and sleep current is reduced by dynamic voltage and frequency

scaling (DVFS), reverse body bias (RBB) and power domain management (PDM).

Both RBB and PDM require that application circuit design integrate these functions. PDM is managed by the system application.

signal processes, embedding a CPU requires much less silicon area compared to only a few year ago, so the flexibility of a more general solution does not add appreciably to the total cost. Such CPUs are similar to those used in

figure 1

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The active power can be reduced by employing a technique known as forward body bias (FBB). This method that is integrated into the design reduces the power required for fast clocking. Typically it is managed by the system and used when high speed is required. Coupling this technique to DVFS can reduce active power by 25 percent while also reducing the bias power.

These circuit techniques help improve standby and runtime in portable applications. However, they do require collaboration between the power sub-system and application system.

There are certainly analog power solutions that offer a system interface for voltage adjustment as well as power shut-down. However, digital power control provides a greater degree of power control and management that can be used to address higher levels of power management complexity.

Digital Power Solutions

Figure 2 depicts a general digital power controller. Such a controller may use hardwired state-machines or embedded CPU for general processing of communication, configuration and housekeeping tasks. In todayâ&#x20AC;&#x2122;s mixed

portable applications for general user interface and system management, and have high MIPS per milliwatt rating. Many digital power solutions also embed non-volatile memory for configuration as well as recording real-time system information.

The digital controller typically has at least one communication interface. An industry standard interface is PMBus. This interface is similar to SMBus, which is often found in portable devices for battery management.

The PMBus can be used to monitor the various power parameters enabling the system to make choices about operating modes. The PMBus also can be used to configure the digital control prior to operation to set output voltage, sequencing, and response to operating and fault conditions. During runtime, the PMBus can be used to adjust the power supply for the desired output voltage as well as other power dynamic characteristics.

Figure 2 also shows other functions generally provided in a digital power solution such as a general-purpose ADC for analog signal monitoring, support circuits such as references and oscillators, and general-purpose I/O and timers. These peripherals can be configured to JULY 2008

33

portable power

provide the required functions for housekeeping and system control.

The primary differentiator is the digital compensation controller. This circuit is comprised of a high-speed analog-to-digital block, a digital compensator block, and a digital pulse width modulator block. A digital power

be adjusted for various operating modes. For example, in lower power modes the switching frequency may be reduced. In this case, the compensator can be adjusted to provide the proper loop response given this lower power and frequency mode.

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exploration into products, technologies and companies. WhetherDigital your goalPower is to research the latest datasheet from a company, Controller mp to a company's technical page, the goal of Get Connected is to put you in touch with the right resource. Whichever level of gy, Get Connected will help you connect with the companies and products you are searching for.

onnected

End of Article Get Connected

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34

integrated circuit may have more than one of these compensators. The advantage of multiple compensators/output control blocks is that sequencing and tracking can be very flexible and configured within one IC. Multiple blocks can share common resources such as references, oscillators and system interface hardware.

The digital compensator block generally has programmable loop compensation registers.

The registers are used to configure the compensation filter for the proper loop response. The advantage of a configurable filter is that it can

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Digital Flexibility in Portable Applications

Integrating more and more functions in portable applications has become the norm. Along with this functionality comes a broad range of operating modes and active power. Digital control allows the designer to adapt to these conditions. One example of adaptability is the ability to perform non-linear compensation. A simple approach to non-linear is to express the compensation as PID (proportion, integral, differential) as shown in Equation 1.

Equation 1. PID Compensation:

G s K p

Kd s2 K ps Ki Ki sK d s s

KP is the proportion gain Ki is the integral gain Kd is the differential gain The KP can be made a function of the difference between the desired voltage and the measured voltage, the error term. Using the values from the high-speed data converter in the

About the Author

portable power

The combination of non-linear compensation with complex decision configuration, digital solutions can help reduce power losses during conversion as well as control the operational voltage to take advantage of other system-level power saving methods.

As the power industry continues to develop digital power control1.6 lers, these devices will 1.55 become an important part of portable power 1.5 solutions.

Volts

loop compensation path, KP , can obtain from a table based on the magnitude and direction of the error. Figure 3 shows the case where small error values use linear compensation (KP held constant). But as the error becomes great due to a transient, the gain is increased starting at errors of ±20mV. This non-linear method can be applied to compensate during operating modes where the load will vary greatly. Another aspect of digital control is the ability to switch between compensators as a function of operational modes. For example, during standby or sleep modes, compensation may be selected for stability but with a narrow linear compensation range so that if the mode changed suddenly, the compensation could maintain the desired output.

For applications using multiphase regulators like those for processors and graphics processors, digital provides phase management solutions that allow phase shedding and adding based on load requirements. Although phase management can be done with analog power solutions, digital solutions can be more adaptive. Even in a two-phase solution, there are benefits in selecting the best phase of the two for low power operation. Additionally, temperature inputs to phase management may be important. Simply balancing the current between two-phases may result in one phase continuing to get hotter, given the positive temperature coefficient of the loss components. Hence, in the digital multiphase controller, phase temperature can be added to the phase current balancing algorithm.

figure 3

1.45 1.4 1.35

David Freeman is 1.3 an Engineering Man1.25 0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45 0.5 ager in System Power Milliseconds Products at Texas Instruments where he manages systems en2A to 12A transient, blue is linear and red is non-linear. gineering and is a core member of TI’s digital power team. David also writes a monthly opinion column in Portable Design magazine, “Dave’s Two Cents.” David has 16 years experience in power-related areas with a strong focus in portable power management, is a Texas Instruments Fellow, and has 18 patents related to power and battery management.

Texas Instruments Inc., Dallas, TX. (800) 336-5236. [www.ti.com].

Conclusion

Benefits from a digital power solution are derived from the flexibility of the solution.

Although digital power solutions have been used for more than a decade, it has only been recently that the solutions have been able to address high-frequency switch-mode operation required in portable applications. However, generating the required duty-cycle resolution at high frequencies must be done with low power operation in mind. By minimizing the high-speed circuit components and taking advantage of smaller process geometries, digital power solutions have become practical for portable appliances.

JULY 2008

35

portable power battey management

Smart Battery Management Considerations for Portable Applications New battery technologies and leading-edge applications are constantly pushing the limits of existing battery management systems. Systems that can currently support the latest trends may end up being outdated and insufficient to support future applications.

by Ravi Pragasam, Senior Manager, Fusion Product Marketing, Actel Corporation

P

Portable applications need the support of battery management systems to ensure that the productivity of batteries is maintained and to deliver the best power profile over the batteriesâ&#x20AC;&#x2122; lifetime. In most applications today, batteries need to be replaced often and a system that can offer a means to have efficiently managed so as to prolong its life can offer several benefits. In addition to a lower overall cost since the consumer will not have to continually purchase new batteries, prolonging battery life means fewer battery replacements, which in turn means less waste.

Increasingly, consumers acknowledge the need for smart battery management from a cost and environmental impact perspective. Laptops, cell phones and handheld devices like cordless drills and vacuum cleaners require longer run times, longer lifetimes and more end-user confidence in the battery information. And, proper handling of the battery results in the longest

36

PORTABLE DESIGN

possible life for that battery. One of the biggest challenges for typical management schemes has been the ability to recognize and support batteries of different technologies and chemistries.

Traditionally, many designers believed battery optimization could be achieved using a standardized smart battery that includes all the necessary electronics to monitor itself and communicate to the greater system. However, today, the smart battery concept defines interfaces, a data set and behaviors of the smart battery, battery selector, smart charger and host elements in a smart battery system. A smart battery management system generally contains an analog monitoring chip whereby the voltage, current and temperature of the battery cell need to be measured; a digital controller chip, which is used to issue the right commands to implement the re-charging function; various discrete diodes, transistors, passive components; and a redundant safety monitor chip.

portable power Smart battery management systems typically use off-the-shelf components to support a wide variety of battery types (Figure 1). However, new battery technologies and leading-edge applications are constantly pushing the limits of existing battery management systems. Systems that can currently support the latest trends may end up being outdated and insufficient to support future applications. The answer to this could be the use of a flexible and programmable platform that can be repurposed to support next-generation applications without any major re-haul of the design.

Certainly, when choosing a smart battery management approach, a number of factors should be considered, including cost; other required external hardware, such as temperature sensors and stable oscillators; level of standardization or, conversely, flexibility and programmability; development support; and the power consumption of the monitoring circuitry.

from its sleep state, there is no loss of state and the application starts up where it left off. Offthe-shelf battery management systems use external memory devices to store the contents of the system when it is placed in a sleep mode.

The battery management system can also be used to scale voltages based on the different inputs to the system. To implement the different functions above, an off-the-shelf system can use voltage scalars that can handle a wide variety of voltages.

figure 1

+Terminal

Smart Battery Management Functions

MCU (Interfacing I2C and EEPROM)

Smart Battery Protection and Monitoring Controller

2nd Protect

A smart battery management controller must be able to measure the voltage of each individual cell within the battery pack and should be able to sense the status of the application. An off-the shelf smart battery management system could use independent voltage, current and temperature monitoring components to monitor the various physical parameters to gauge the status of the cell. Part of the function of the analog blocks within the system is to sense the application status and take the required action.

The system also has the responsibility to ensure that it places the application in a stand-by or sleep mode when the application is not being used to conserve power and extend battery life. For example, if the portable application is in a stand-by or shutdown mode, then the battery management system needs to make sure that the correct amount of charge is available for the operation of the application without any loss of content.

Another function of a smart battery management system is to ensure that when the application is placed in a stand-by or sleep mode, the current state of the application is saved someplace so that when the application wakes up

Fusion -Terminal

RSENSE

A typical Smart Battery implementation using off-the-shelf components.

One of the greatest advantages of a smart battery management system is the power-management possibilities it offers to a system engineer. Using information from a smart battery management system, you could cater sensitivity to the reported battery state. If you know a battery is empty, you could design the system to apply the full charge current. Once the battery fills up, the system could increase the sensitivity to identify the end-of-charge point very closely.

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portable power

A Traditional Approach to Smart Battery Management

A traditional smart battery management approach would be to use discrete off-the-shelf components to implement the application.

Typically, an analog-to-digital converter (ADC) performs the task of converting the analog functions into a digital format. The physical parameters that are measured such as current, voltage and temperature are converted into a digital form and are then processed by a microcontroller to enable a decision based on the system status. If the voltage is not within a specified range or needs to be maintained within a specific range, this information is then relayed back to the battery management system to ensure the correct operation of the portable application.

An off-the-shelf ADC can be used for this purpose with a resolution of 12 bits and an ac-

figure 2 Bank 0

Bank 1 CCC SRAM Block 4,608-Bit Dual-Port SRAM or FIFO Block

OSC I/Os CCC/PLL

Bank 2

Bank 4

VersaTile

ISP AES Decryption

User Nonvolatile FlashROM

Flash Memory Blocks

Analog Quad

Analog Quad

Analog Quad

CCC

Analog Quad

Flash Memory Blocks

ADC

Analog Quad

Charge Pumps

Analog Quad

Analog Quad

Analog Quad

Analog Quad

Analog Quad

Bank 3

Fusion device architecture overview (AFS600)

38

PORTABLE DESIGN

SRAM Block 4,608-Bit Dual-Port SRAM or FIFO Block

curacy of about one percent or less. The same process is in place when the current is being measured or the temperature is being measured. There are available off-the-shelf current and temperature monitors that can be used to provide the appropriate current and temperature measurement to the ADC, which in turn performs the conversion and provides the information for further processing by the battery management system. After processing, the decision, which is in digital format, is then converted back into an analog format that is used to control a physical parameter on the outside like turning the charge capacitor on or switching the system to back-up. When there is a need to save the application state before going into a sleep mode, the microcontroller saves the current state of the application in a memory device before shutting down. When the system is awakened, the state is retrieved from the memory device and loaded back into the system so that upon wake-up the system starts up from where it left off.

Once the information about the amount of charge is obtained, the next phase of the application is to decide the action that needs to be implemented that is based on a pre-determined application. The decision could be to place the application in a sleep mode since there is no activity and the charge needs to be conserved.

Or the decision could be that there needs to be a shutdown process since there is an emergency and the application has exceeded some pre-determined limits. Or the decision could be to supply more charge to the system as the power has been drained in the system. Lastly, the decision could be to switch the system to a back-up system since the generic system has now been depleted of its power. Off-the-shelf microcontrollers are generally used to implement these decision-making steps that are then converted back to an analog format and output to the system.

When the individual functions for the smart battery system are implemented using discrete components, it could add several devices based on the complexity of the application. As additional functionality gets added in and the system grows in device count, the system design becomes more and more complicated. But this

portable power still does not address any feature changes or functions that could be added in the future to make the system scalable. Microcontrollers offer some feature integration, offering built-in analog inputs, ADC and DAC, clock circuits and a CPU core to make decisions. But when it comes to scalability, a microcontroller may not have the programmability and flexibility that is needed to support this requirement

Using PSCs for Smart Battery Management

Another approach to solve this problem is to use a platform that offers integration along with flexibility and scalability. Programmable system chips (PSCs) are becoming more and more ubiquitous, and with their ability to offer programmability and flexibility, they are achieving greater prominence in applications that have a need for upgrading in the future.

An ideal platform would be one whose features include both analog and digital functionality along with the ability to add intelligence in the form of a soft processor core; it may support all the features needed for a smart battery management system. One such option is the Fusion PSC as shown in Figure 2 that offers an analog block with multiple analog inputs that interface with a 12-bit ADC with the optional pre-scalars for voltage scaling. The analog block also includes several monitoring functions such as voltage, current and temperature. The PSC also includes several clock features to implement wake-up and stand-by features. With the addition of an optional soft processor core, intelligence can be achieved that can be used to prompt the system to transition into a sleep mode wake-up from a sleep mode when needed.

Leveraging a PSC solution provides the required programmability and flexibility to keep pace with changing battery technologies and emerging applications, but also enables overall board space reduction. With the ability to integrate several discrete components and functionality into a single chip, along with the battery management function, designers can realize tremendous board, power and cost savings that canâ&#x20AC;&#x2122;t be achieved using a discrete approach.

Summary

When selecting a solution to implement a smart battery management system, it should be ensured that the system is able to offer the consumer the ability to prolong the battery life of the portable application while providing the option to be upgraded for future enhancements with no major design revisions and with less additional cost. While traditional off-the-shelf components offer an adequate solution, newer technologies may offer higher integration and flexibility and need to be considered as a viable solution. Smart battery management will continue to play an important role in portable applications and, with new options available, designers can easily implement a highly efficient solution.

Actel Corporation, Mountain View, CA. (650) 318-4200. [www.actel.com].

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39

product feature Handheld Real-Time Spectrum Analyzer for Digital RF Troubleshooting 6.4 GHz, 20 MHz bandwidth, integrated GPS/mapping in a portable design.

by John Donovan – Editor-in-Chief Your Bluetooth design is due out the door, but it’s acting strangely. The hopping channels keep changing erratically as if your adaptive frequency hopping spread spectrum (FHSS) device is trying to avoid some sporadic interference.

Is it a bug or just interference? With a new hop every 625 μsec and a hop time of just 359 μsec at 2.4 GHz, the chances of your traditional spectrum analyzer catching a sporadic interferer in a timely manner are close to zero.

Swept-tuned and step-tuned spectrum analyzers can’t provide 100% probability of intercept (POI) for a signal that isn’t continuously present, since they spend only a short period of time tuned to each small portion of their frequency span during each sweep; if something happens in any part of the span other than where it is tuned at that instant, that event will not be detected or displayed. FFT-based analyzers, including vector signal analyzers, also miss signals during the time between acquisitions.

RTSAs, on the other hand, capture data across all frequencies within their real-time span during every acquisition.

Tektronix has just introduced its latest RTSA, the handheld SA2600. With a frequency response of 10 kHz to 6.2 GHz and a real-time bandwidth of 20 MHz, the SA2600 provides 100% POI for signals with minimum event durations of 500 microseconds (shorter signals will be captured, but the accuracy of their amplitude can’t be guaranteed). By comparison, the

40

PORTABLE DESIGN

fastest Swept Spectrum Analyzer (SA) with 50 sweeps per second requires pulse durations longer than 20 milliseconds for 100% POI with full accuracy.

Digital phosphor (DPX) waveform image processor technology in the SA2600 displays the live spectrum by processing >2,500 spectrum measurements per second. The SA2600 is designed to offer benchtop performance on a portable handheld platform, specifically to solve problems created by digital RF technologies from WiFi to WiMAX to UWB and UMTS. Though a portable device, the SA2600 boasts excellent displayed average noise level (DANL: –153 dBm, 10 MHz to 2 GHz, 10 Hz RBW), making it possible to detect very low-level signals; wide spurious free dynamic range (SFDR)—10 kHz – 6.2 GHz; low phase noise (≤ -95 dBc/Hz @ 10 kHz offset) and easy LAN networking capabilities. Third-order IMD is ≤ –70 dBc for two tones at or below the reference level, preamp off, all gain settings Auto-coupled.

The SA2600 can handle general-purpose spectrum measurements, including surveying the RF spectrum, mapping received signal strength and resolving spectral interference disputes. In addition, it has a variety of unique features such as visual and audio signal strength indicators and integrated GPS measurements’ mapping with direction-finding vectors for easy location of signal emitters. It incorporates a unique touch-screen interface that allows very fast tuning and zooming in and out on signals, improving operator efficiency when working across a wide range of frequency bands. The SA2600 features a large 10.4-in. transflective color VGA LCD display. The whole package weighs in at just over 12 lb.

You can use the SA2600 to test and troubleshoot just about any digital RF design. Or you can plug in one of the optional beam antennas and track down that pesky interference that’s been causing you headaches. All told, the SA2600 is a well designed piece of test equipment that addresses the challenges of next-generation wireless designs. The fact that it’s also a nice example of portable design is itself a plus.

design idea Adjustable Hysteresis in Microprocessor-Reset ICs

figure 1

Eric Schlaepfer, Maxim Integrated Products Inc., Sunnyvale, CA

VIN

Microprocessor-based systems often include one of the many available 3-pin microprocessor-reset ICs. These devices monitor a single power supply rail, and provide a system reset signal in response to undervoltage conditions. Normally such ICs exhibit a fixed hysteresis (the voltage difference between rising and falling thresholds on VCC), but a simple circuit (Figure 1) lets you adjust that voltage difference.

As VIN rises above 1.0V, the /RESET\ output asserts low to indicate that the input voltage is below the monitoring threshold. Current flows from VIN through RP to the internal MOSFET driver and through RH to ground, developing an offset voltage across RH. Because the internal voltage reference is referred to GND, the offset voltage adds to the VCC rising threshold. The new rising threshold can be calculated as follows:

V TH _ RISING = V TH ⋅

VCC

0.1uF

MAX 6383 RESET

RESET

GND

RH + RP RP

When VIN crosses this rising threshold and remains above it for the reset timeout, /RESET\ de-asserts and current through RH drops, allowing the VCC threshold to shift back to its normal level.

Consider a microprocessor-reset IC (MAX6383XR31D1) with 3.08V threshold and pull-up resistor (RP) of 10kΩ. If you want the rising threshold to be 3.18V (100 mV hysteresis), solve the above equation for RH (neglecting supply current and the finite on-resistance of the MOSFET output driver), and obtain 324.68Ω. The closest value in standard 1% resistors is 324Ω.

An oscilloscope photo (Figure 2) shows the circuit operation. The measured rising threshold is 3.1984V and the falling threshold is 3.0891V, producing 109.3mV of hysteresis. The 9.3 mV discrepancy (with respect to the calculated value of 100 mV) is attributed primarily to MOSFET on-resistance, supply current into the device and resistor tolerances.

Note that RH increases the /RESET\ output VOL (logic-low output voltage) by the hysteresis voltage. In this case, VOL measures a maximum of 127 mV. You should therefore check to ensure that circuitry connected to /RESET\ can tolerate the higher VOL.

RP

RH

In this circuit, the RH and RP values let you adjust the hysteresis that determines RESET timing.

figure 2 Δ: @:

100mV 3.18V

TRIGGER A Trig Type Edge Video Mode Auto Normal Source Ch: 1 2 3 4 Alt Ext Ext/10 AC Line Coupling DC Noise HF Reject LF Reject Slope

Ch1

200mV

Coupling DC AC

Ch2

2.00 V

M400ms A

VERTICAL (CH1) Impedance Bandwidth Full 1MΩ 50Ω

Ch1

3.08 V

ACQUIRE Fast Trig Mode Normal Sample

CURSOR Off HBar VBar

These waveforms from the Figure 1 circuit show 100mV hysteresis. That is, the difference in volts at which VCC (CH1) intersects the rising and falling edges of /RESET\ (CH2) is 100 mV.

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PORTABLE DESIGN

products for designers NXP Real-Time Clock Sets New Record in Power Efficiency NXP Semiconductors has announced the availability of the industry’s best low-power performance real-time clock (RTC) chips with SPI bus interface, the PCF2123. Operating at a current of less than 100 NanoAmperes (0.15 uW) on a 1.5V power supply, the real-time clock comes in a tiny 3 x 3 x 1mm package, making it ideal for battery operation and handheld applications to keep track of time, when the equipment is powered down. The small size and low-power requirement of the PCF2123 make it a good choice for applications including home-use medical devices such as blood pressure monitors, portable phones, PDAs and similar compact portable electronics products where space and power are critical, while the variety of features makes it suitable for industrial systems as well as white goods.

“Power consumption is probably the most important feature of RTCs, directly correlated to the battery life of the electronic equipment,” said Markus Hintermann, international product manager, interface product line, NXP Semiconductors, in an interview with Portable Design. “Three parameters are very critically watched during system design including accuracy, power consumption and size. Using precision engineering, NXP has been able to develop a groundbreaking real-time clock that can save 50 percent or more power.”

Features of the PCF2123 real-time clock include a freely programmable alarm and timer function that gives designers the option to generate a wakeup signal on an interrupt pin. A programmable offset register also allows fine-tuning of the clock and frequency adjustment. The seconds, minutes, hours, days, weekdays, months and years registers are all coded in binary-coded decimal (BCD) format for easy conversion to decimal digits for printing or display and faster decimal calculations. Data is transferred serially via an SPI bus with a maximum data rate of 6.25 Mbits per second.

Accuracy on the real-time clock is maintained by using a quartz reference. Each of these CMOS-based, real-time clock/calendars uses a low-power 32.768 kHz quartz oscillator to provide clock and calendar functions. The calendar functions track year, month, date and day with built-in century and leap-year flags. The tolerance of the quartz and the physical environment around the quartz crystal and oscillator circuit can be easily calibrated via the on-chip calibration register. No other external parts are required.

Real-time clocks are indispensable for time keeping, process control and other time-critical tasks found in time-keeping applications, battery-powered stand-by devices, and in metering units. The PCF2123 is a CMOS real-time clock and calendar optimized for low power consumption. It functions as the time manager accurately keeping time, controlling the periodic wake-up of the microcontroller core from hibernation mode, and providing a watchdog function to independently monitor microcontroller tasks. With power consumption at less than 0.15uW the RTC can be powered by a very small battery cell or a small super-cap. Housed in tiny 3 x 3 x 1mm leadless package, the RTC fits nearly anywhere, minimizing the space needed to host this important timing and measurement function.

Samples of the PCF2123 real-time clocks are available now. At high volumes, U.S. pricing for the PCF2123 is $0.55. Volume shipping begins in Q2 2008.

NXP Semiconductors, San Jose, CA. (408) 474-8142. [www.nxp.com].

Class-D Amplifier Features Dynamic Range Compression and Speaker Protection Texas Instruments has introduced a highly advanced, filter-free, stereo Class-D amplifier that provides a 1.7W per channel output drive capability across an 8-ohm load and improves overall volume versus traditional Class-D products. The new amplifier incorporates programmable dynamic range compression (DRC) that automatically adjusts the audio to the desired loudness range while protecting the speaker and preventing clipping and distortion. In addition, the chip’s flexibility and intuitive support tools ease design and speed time-to-market for manufacturers of wireless handsets, personal navigation devices, notebook PCs and portable DVD players.

To address the need for louder volume from the speaker, the TPA2016D2 incorporates DRC to automatically boost soft volumes.

Conversely, DRC enables designers to compress the dynamic range of the audio to match the dynamic range of the speaker in order to reduce disturbingly loud volumes that cause clipping and distortion. The DRC functionality also protects the speaker from damage at high power levels to avoid field failures. In addition, the DRC capability in the TPA2016D2 frees up to 20 percent of MIPS in the digital signal processor (DSP) for other functions.

The DRC can be programmed via digital I2C control and provides designers with the flexibility to specify the design parameters that optimize their system’s audio performance. For instance, users can select gains from -28 dB to +30 dB as well as program attack/hold/release times, compression ratios and noise threshold values.

Evaluation modules (EVMs) with software, including user-friendly graphic user interface (GUI), illustrate the complete flexibility of DRC. The GUI includes a dynamically changing graphical plot that visually depicts the input-output relationship for easy comprehension and rapid evaluation to speed time-to-market.

The TPA2016D2 Class-D amplifier is available now from TI and its authorized distributors in a space-saving 2.2 mm x 2.2 mm, NanoFree WCSP package. Suggested resale pricing is $1.60 in 1,000-unit quantities.

Texas Instruments Inc., Dallas, TX. (800) 336-5236. [www.ti.com].

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PORTABLE DESIGN

Audio Codec for Portable Devices Extends Playback Time up to 40 Hours Wolfson Microelectronics has announced the launch of its WM8903 CODEC—the first in the next generation of ultra-low-power audio devices, including portable media players, multimedia handsets and handheld gaming systems.

The WM8903 features Wolfson’s new SmartDAC technology, a low-power DAC capacitor-switching architecture. This enables DAC-to-headphone power consumption of just 4.4 mW and includes a capability for programmable “performance vs. power” profiles, allowing system designers to optimize for each usage scenario, such as docked or on the move.

The WM8903 also includes Wolfson’s Class W amplifier technology, an evolution of class G and H, featuring an adaptive dual-drive charge pump and DC servo circuit architecture. The Class W headphone amplifier technology intelligently tracks the actual music signal level and uses an adaptive dual drive charge pump to optimize power dissipation. The WM8903 can also operate from a common 1.8V supply for both analog and digital power rails. With a significant power supply rejection ratio (PSRR), the WM8903 can share noisy power supply rails with other digital devices with no performance compromise. This architecture not only optimizes power consumption but also eliminates the need for large DC blocking headphone capacitors, enabling significant savings in PCB space and the audio subsystem bill of materials (BOM). It also brings additional audio benefits through an improved bass response.

The WM8903 is available for sampling now in a thin 40-pin, 5 x 5 x 0.55 mm QFN package. It is priced at $1.80 per unit in volumes of 10,000 units.

Wolfson Microelectronics, Inc., San Diego, CA. (858) 676-5090. [www.wolfsonmicro.com].

Cypress Semiconductor has announced the TrueTouch touchscreen solution based on the PSoC programmable system-on-chip architecture.

The TrueTouch offering includes a single-chip touchscreen solution that can interpret up to 10 inputs from all areas of the screen simultaneously. This capability, known as “multi-touch all-point,” enables designers to create new usage models for products such as mobile handsets, portable media players (PMPs), GPS systems and other products. Examples of applications well-suited for multi-touch all-point functionality include keyboard implementations, inputting multiple locations into a GPS, playing video games on a mobile handset, and making multiple adjustments to sound and/or video settings on a PMP. In addition to the multi-touch all-point products, the TrueTouch family includes devices that perform traditional touchscreen functions including interpreting single touches, and gestures such as tap, double-tap, pan, pinch, scroll and rotate.

Because of the flexible and programmable TrueTouch architecture, customers can choose to work with a wide variety of touchscreen vendors and/or LCD module vendors to create their designs. In addition, the TrueTouch solution utilizes the PSoC architecture’s ability to integrate additional functions such as driving LEDs, backlight control and I/O expansion. These functions, in conjunction with flexible communication options (I2C and SPI), allow for flexible system integration for touchscreen systems.

The TrueTouch family includes the CY8CTST1xx single-touch devices; the CY8CTMG1xx multi-touch gesture devices; and the CY8CTMA100 multi-touch all-point device. The products, offered in 32- and 56-pin QFN packages, are expected to sample in August with production in September.

Cypress Semiconductor, San Jose, CA. (408) 943-2600. [www.cypress.com].

Low-Cost Vector Signal Generator, Analyzer for Mobile WiMAX/MIMO Keithley Instruments has announced a set of signal creation and analysis tools that extend its RF test capabilities to include WiMAX signal testing. Keithley’s new solution is built on a DSP-based Software-Defined Radio (SDR) hardware platform that makes it simple and inexpensive to add support for new signal standards, such as 802.16e mobile WiMAX Wave 2 testing with up to 4x4 MIMO channels, without requiring expensive hardware upgrades or different instrumentation. Keithley’s test systems provide frequency coverage from 400 MHz to 4 GHz and to 6 GHz if WLAN measurements are needed.

The Model 2820 RF Vector Signal Analyzer is optimized for automated testing of wireless devices in production test environments, as well as in new product and device research and development. Keithley’s Model 2820 is the lowest cost, widest signal acquisition bandwidth, stand-alone vector signal analyzer with both manual and automated operation on the market today. The Model 2820 RF Vector Signal Analyzer is designed to work closely with Keithley’s Model 2920 RF Vector Signal Generator.

Working in conjunction with the two RF test instrument families is Version 2.0 of Keithley’s SignalMeister Waveform Creation Software, for creation of the entire range of signals in accordance with WiMAX and WLAN wireless connectivity standards and 3GPP and 3GPP2 cellular standards.

SignalMeister is an expandable software platform with a common user interface that allows creation of waveforms from multiple signal standards with optional additive signal impairments and channel modeling in a single environment. Users download the waveforms they create to any Keithley Series 2900 RF Vector Signal Generator.

The base prices of the Model 2820 and Model 2920 instruments at 4 GHz are $22,500 and $17,500 respectively. SignalMeister can be downloaded from Keithley’s Web site at no charge; specific software licenses start at $2,500.

Keithley Instruments, Inc., Cleveland, OH. (440) 248-0400. [www.keithley.com].

Smallest 1A, 4 MHz Synchronous Step-Down DC/DC Converter for Portable Applications National Semiconductor has introduced the industry’s smallest 4 MHz synchronous step-down DC/DC converter that provides up to a 1A output current over an input voltage range of 2.3V to 5.5V. The LM3691 DC/DC converter is optimized for powering high-performance processors from a single Li-Ion cell battery in mobile phones, personal media players and other mobile devices. A member of National’s PowerWise energy-efficient product family, the LM3691 features peak efficiency of 95 percent, low quiescent current to maximize battery life and output voltage precision of ±1 percent to power baseband and next-generation applications processors.

National’s new LM3691 DC/DC converter is offered in a micro SMD package and features high switching frequency up to 4 MHz that enables use of miniature 1 uH multilayer inductors and tiny 4.7 uF capacitors for a solution size of less than 15 mm squared. Several fixed output voltage options are also available.

National’s LM3691 DC/DC converter features excellent transient performance of ±40 mV for stable output voltages. An integrated mode-control pin allows the design engineer to select forced pulse-width modulation (PWM) mode or auto mode, which changes modes between economy or ECO (gated PWM mode) and PWM automatically, depending on the load. In ECO mode, the LM3691 offers superior efficiency and very low quiescent current at 63 uA under light load conditions. ECO mode extends the battery life through reduction of the quiescent current during light load currents and system standby. The LM3691 is offered in a 6-pin, 1.26 mm by 1.56 mm micro SMD package.

Available now, the LM3691 is priced at $2.25 each in 1,000-unit quantities.

National Semiconductor Corporation, Santa Clara, CA. (408) 721-5000. [www.nsc.com].

JULY 2008

43

products for designers

Multi-Touch All-Point Offering on a Single Chip

products for designers

Single-Chip Bluetooth + GPS + FM Transceiver CSR has announced its seventh-generation BlueCore silicon.

BlueCore7 is the world’s first single-chip solution to combine Bluetooth v2.1+EDR, Bluetooth low energy, eGPS (enhanced Global Positioning System), and FM transmit and receive capabilities. CSR’s BlueCore7 significantly reduces the power, size, cost and complexity of adding multiple radios into a mobile phone and demonstrates the company’s continued expertise in embedded wireless technologies.

CSR has integrated Bluetooth low energy, eGPS and FM Tx and Rx technologies into BlueCore7 alongside an enhanced Bluetooth v2.1 + EDR radio that delivers +1 dBm Tx and -91 dBm Rx. These enhancements help BlueCore7 to extend the overall range and across-body performance to provide better audio quality. BlueCore7 includes CSR’s proprietary AuriStream voice CODEC, which produces the quality of a fixed line call when using a Bluetooth connection and is capable of a 30% reduction in power consumption.

Demonstrated at this year’s Mobile World Congress, CSR’s eGPS technology is an innovative approach for making location-based technologies a viable proposition for mobile handsets. By sharing resources with the Bluetooth radio and leveraging memory and processing already available on the host platform, CSR has reduced the cost and made significant power and performance improvements necessary for embedding GPS functionality into a mobile handset. Current GPS technologies only meet the basic needs of consumers and regulatory requirements. CSR’s eGPS provides users with faster and more accurate position information, on demand and in all environments—even deep indoors.

By integrating a transmit and receive FM radio with Bluetooth, handset designers can offer these features using less space, fewer components and at a lower cost. BlueCore7 allows the Bluetooth and FM radios to work without interference, either independently or together to allow users to stream FM radio from a handset to a pair of Bluetooth headphones.

CSR’s FM receiver boasts -110 dBm of sensitivity, securing high quality FM reception even in difficult environments. To overcome the challenges of using a handset’s internal FM antenna, the FM transmitter has a uniquely high maximum output power of +4.5 dBm. BlueCore7 is sampling now in QFN and WLCSP packaging and will be in volume production in Q4 2008. Contact CSR for pricing.

High Ripple-Rejection, Low-Dropout, High Output Current CMOS Voltage Regulator The S-1155 Series LDO, developed based on CMOS technology, is a positive voltage regulator with a super low dropout voltage, high output voltage accuracy and low current consumption. Applications include constantvoltage power supply for portable equipment and battery-powered devices.

The S-1155 Series provides the very small dropout voltage and the large output current due to the built-in transistor with low onresistance. The over-current protector prevents the load current from exceeding the capacitance of output transistor. The thermal shutdown circuit prevents damage caused by heat; the rush current control circuit limits the excessive rush current during start-up.

The ON/OFF circuit ensures longer battery life. Various capacitors, also small ceramic capacitors, can be used for this IC more than for the conventional regulator ICs, which have CMOS technology. The small package SOT-89-5 enables high-density mounting. Features include: •O utput voltage: 1.0 to 5.0V, selectable in 0.05V step.

• Low equivalent series resistance capacitor : Ceramic capacitor of 4.7 µF or more can be used as the I/O capacitor.

• Input voltage: 1.5 to 5.5V • High-accuracy output voltage : ±1.0% (1.0 to 1.45V output product : ±15 mV) • Low dropout voltage : 70 mV typ. (3.0 V output product, at IOUT = 200 mA) • Low current consumption: During operation : 70 µA typ., 90 µA max.

(3.0 V output product); During shutdown : 0.1 µA typ., 1.0 µA max.

• Output current : 500 mA (3.0V output product, at VIN = VOUT(S) + 1.0 V)*1 Seiko Instruments USA Inc., Torrance, CA. (310) 517-7770. [www.sii-ic.com].

CSR (Cambridge Silicon Radio), Richardson, TX. (214) 540-4300. [www.csr.com].

6 GHz, High-Definition Oscilloscope LeCroy Corporation has announced the launch of the WavePro 7, the first product series in the new Zi Family of oscilloscopes. The launch represents the first deployment of LeCroy’s next-generation chipset and latest streaming architecture, X-Stream II, allowing the WavePro 7 to deliver raw performance, speed and analysis capabilities unmatched in the industry. The WavePro 7 oscilloscope is the only complete debug solution with up to 6 GHz of bandwidth available. LeCroy claims that new X-Stream II proprietary architecture delivers 10 to 20 times faster response rates, with long memory handling in a new industrial design.

The WavePro 7’s advanced industrial design incorporates an industry-first 15.3 inch, 16:9 high definition display equipped with a touch screen. Equipped with the industry’s most extensive toolbox, the new scope can solve electronic design problems within minutes instead of hours and can be extended to an integrated second display in order to expand the oscilloscope’s workspace. The WavePro 7’s removable front panel allows engineers to place the control-pod next to the circuit under test. LeCroy’s new serial interface bus, LSIB, enables data to be transferred 10-100 times faster than any other method. In addition, TriggerScan and WaveScan, special modes for finding rare events, shorten the time to debug a new design.

LeCroy also launched a new line of serial data analyzers, SDA 7, and disk drive analyzers, DDA 7, which feature the same speed, power and performance capabilities as the WavePro 7 Series.

LeCroy Corporation, Chestnut Ridge, NY. (845) 425-2000. [www.lecroy.com].

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PORTABLE DESIGN

Communications Platforms for Embedded Multicore Technology Freescale Semiconductor has introduced a new brand of communications platforms designed to enable the next era of networking and take embedded multicore to new levels of adoption. The new QorIQ platforms are the next-generation evolution of Freescale’s PowerQUICC processor line and are designed to help developers migrate to multicore with confidence.

QorIQ platforms include single, dual and many core processors—all based on Freescale’s e500 Power Architecture technology. The platforms start with the P1 and P2 levels, which consist of five package-, pin- and software-compatible processors designed to ease the transition from single- to dual-core processing. The P3 and P4 platforms enable developers to move into the “many core” arena and address more advanced processing needs. The P5 platform is designed to deliver Freescale’s highest-performing solutions well within embedded power budgets. All of the QorIQ platforms are equipped with extensive programming support to help developers get the most out of their multicore implementations.

Freescale’s QorIQ platforms are unified in their use of high-performance e500 Power Architecture cores. These cores offer frequencies ranging from 400 MHz to 1.5 GHz. Products at the high end of the QorIQ portfolio also feature breakthrough embedded processing innovations that boost performance, including private backside cache per core, datapath acceleration architecture (DPAA) and CoreNet coherency fabric.

QorIQ platforms start at 45nm geometries and offer a roadmap to 32nm and beyond. Products based on QorIQ technology are designed to consume significantly less power than other embedded multicore architectures. QorIQ products offered at the 45nm node include solutions ranging from highly integrated products at 4W to “many core” devices under 30W. The QorIQ P3 and P4 platforms allow system developers to strictly manUntitled-1 age device frequency and voltage.

By consolidating on an e500 Power Architecture core-based architecture, QorIQ platforms offer customers an easy migration path to multicore processing, from single- to dual- to eight-core devices. The platforms continue to leverage the broad Power Architecture ecosystem, and Freescale has worked closely with its partners to specifically address common multicore development challenges.

In the high-level QorIQ platforms, on-chip features designed to simplify development include embedded hypervisor technology, code performance monitors, and extensive debug visibility and access. Freescale has also collaborated with virtualized software development firm Virtutech to create a hybrid simulation environment offering a controlled, deterministic and fully reversible environment for the development, debugging and benchmarking of software in embedded multicore environments.

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Freescale Semiconductor, Austin, TX. (800) 521 6274. [www.freescale.com].

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JULY 2008

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products for designers

One Mbit Embedded Reprogrammable Non-Volatile Memory on Standard CMOS Virage Logic Corporation has announced the emPROM Memory System, a new family of embedded multi-time programmable (MTP) non-volatile memory (NVM) for flexible program code storage in System-on-Chip (SoC) devices. Combining user-defined functionality with Virage Logic’s high-capacity read-only memory (ROM) and NOVeA flash memory, emPROM provides secure, fully integrated embedded NVM for SoC designs requiring up to 16 Megabits of code storage and is manufactured on industry standard CMOS processes with no additional mask or process steps. emPROM is specified for a minimum of up to 100,000 program cycles with 10-year data retention at 125°C. The emPROM Memory System addresses the critical issues of SoC code security, performance, power consumption and special process requirements. Most SoC designs in production today use a two-chip solution to implement and execute program code, a flash memory for program storage and the SoC containing the embedded processor, which executes the program instructions. This implementation introduces significant security vulnerability as data crosses chip boundaries from the flash memory to the SoC. This is true even with system-in-package (SIP) implementations where multiple die are combined in a single package. By eliminating the external flash memory device, emPROM improves design security and reliability while reducing system size and manufacturing costs.

There are a few embedded high-density memory solutions available today including embedded flash, one-time-programmable (OTP) and ROM. While embedded flash is available for production at some foundries on mature process nodes, this type of memory requires additional masks and process steps, which increase overall manufacturing costs. In fact, as a result of the additional manufacturing costs incurred by utilizing an embedded flash process, SoC die costs can increase dramatically as the overall die size increases relative to the amount of embedded flash memory required.

By its very nature, OTP memory can only be programmed once, rendering it useless in the event of bit failures or code changes. While ROM offers the lowest cost memory, it is configured during wafer production, making it the least flexible in terms of implementing code changes.

Virage Logic’s emPROM Memory System is available now along with a 90nm reference design. The reference design includes a project license for a 1 Mbit Via ROM, 4 Kbit NOVeA 3.0, emPROM processor, RTL source code and documentation. emPROM pricing starts at $90,000.

2.4 GHz IEEE 802.15.4 FCC-Certified RF Transceiver Module Microchip has announced the MRF24J40MA FCC-certified Radio-Frequency (RF) transceiver module. The new module services the 2.4 GHz unlicensed Industrial, Scientific and Medical (ISM) short-range wireless frequency band for the IEEE 802.15.4 specification, for ZigBee or proprietary wireless-protocol systems. It includes discrete biasing components and an integrated PCB antenna to be used in sensor and control network environments. The module is fully regulatory-agency certified for the U.S. (FCC), Canada (IC) and Europe (ETSI), and is expected to save designers time and money by eliminating the need to receive FCC certification for their wireless products.

Providing a complete short-range IEEE 802.15.4 wireless networking solution, the MRF24J40MA transceiver module is surface mountable and can be used with hundreds of 8-bit, 16-bit, or 32-bit PIC microcontrollers (MCUs). The module is supported by Microchip’s PICDEM Z Demo Kit and the ZENA Wireless Network Analyzer, as well as Microchip’s free ZigBee, MiWi and MiWi P2P (Peer-to-Peer) software-protocol stacks. When combined with these development tools, the module enables designers with little or no RF design experience to design low-power wireless networking products quickly and inexpensively.

A variety of wireless networking applications are appropriate for the MRF24J40MA module, such as industrial monitoring and control, home and building automation, remote control, low-power wireless sensor networks, lighting control and automated meter reading.

Designers looking to incorporate the MRF24J40MA transceiver module into their designs can do so using the PICDEM Z 2.4 GHz Demonstration Kit (Part # DM163027). The kit includes a pair of development boards with a PIC18LF4620 MCU, along with the ZENA network analyzer and wireless network configuration utility. It is available today at www.microchipdirect.com, for $269. Designers can also download any of Microchip’s free ZigBee, MiWi and MiWi P2P protocol stacks from its online Wireless Design Center at www.microchip.com/wireless.

Production quantities of the MRF24J40MA module are available today for $8.99 each in 1,000-unit quantities.

Microchip Technology Inc., Chandler, AZ. (480) 792-7200. [www.microchip.com].

Virage Logic Corporation, Fremont, CA. (510) 360-8000. [www.viragelogic.com].

LTE Simulation Systems for Handset and Base Station Testing Anritsu Company has announced that the company has developed the world’s first Long-Term Evolution (LTE) network simulator and that it is now being used by Anritsu beta customers to help in the development of LTE mobile phone networks. The pre-release introduction of the MD8430A, already compliant with the 3GPP’s evolving LTE standards, supports the efforts of companies designing prototype LTE products, and re-confirms Anritsu’s commitment to take a leadership role in the rollout of LTE. Designed for handset testing, the MD8430A is being complemented by an LTE User Equipment (UE) Simulator for network testing. The test solution can conduct 2x2 Multiple-Input Multiple-Output (MIMO) and 64QAM modulation to achieve 100 Mbits per second data rates with full signaling visibility, which gives LTE mobile phone handset and network equipment manufacturers a crucial time-to-market advantage. Product development will be accelerated with the Anritsu LTE test solution, which helps maximize coverage of relevant test cases required by 3GPP. The first LTE network equipment is expected to be deployed in 2009.

Anritsu Company, Richardson, TX. (972) 644-1777. [www.us.anritsu.com].

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PORTABLE DESIGN

World’s Smallest Load Switch Targets Mobile Applications Micrel Inc. has launched the MIC94040/1/2/3, a new family of high side load switches featuring breakthrough packaging technology. The chips are aimed at a wide variety of high-end portable, battery-powered consumer devices, including smart/feature phones, personal multimedia and navigation, and Ultra Mobile PCs (UMPCs).

Micrel’s innovative version of MLF package technology extends battery life by greatly reducing the on-resistance (RDSON) of the MIC94040/1/2/3 devices down to 28 mohm. Also, superior thermal performance of the new package technology allows more than 3A continuous current from a tiny 1.2 mm x 1.2 mm package, enabling applications such as UMPCs to use the MIC94040/1/2/3 for high current circuits. Each device operates from 1.7V to 5.5V input and can be controlled with very low 1.5V logic due to a novel level shift circuitry that allows it to control higher voltage supplies. The MIC94040 and MIC94041 feature rapid turn on, while the MIC94042 and MIC94043 provide a slew rate controlled Soft-Start turn-on of 116 µs (typical) to prevent in-rush current. In addition, the MIC94041 and MIC94043 feature an active load discharge circuit that ensures capacitive loads are automatically discharged whenever the main switch is in an OFF state.

The MIC94040/1/2/3 are currently available in volume quantities with pricing starting at $0.34 for 10K quantities.

Micrel, Inc., San Jose, CA. (408) 944-0800. [www.micrel.com].

RF Verification With “Turbo” Technology and Comprehensive Electromagnetic Analysis Cadence Design Systems has introduced a new simulation technology to address the challenges of verifying wireless integrated circuits implemented in advanced CMOS process nodes. Cadence has added the “turbo” technology it recently brought to the Virtuoso Spectre Circuit Simulator to its RF analysis. The result is performance improvements of two to five times—sometimes greater—for analysis and verification of large RF circuits targeting advanced CMOS process nodes, and with no degradation in accuracy.

This technology complements a complete manufacturability-aware solution from Cadence for design, implementation and verification of RF integrated circuits (RFICs). Based on the Virtuoso custom design platform, this solution enables designers to deal with the challenge of integrating RF with analog/mixed-signal baseband, and the emerging need for RFICfocused electromagnetic analysis. It improves time-to-market and overall design costs through faster and more accurate verification that reduces design turnaround time and expensive silicon respins.

The complete solution includes the Cadence Virtuoso RF Designer, which brings a full-wave fast planar electromagnetic (EM) field solver to the RF/wireless designer’s desktop. Virtuoso RF Designer offers designers advanced verification capabilities for faster electromagnetic analysis of complex structures and geometries—all within a single design flow, accelerating chip finishing and verification. Virtuoso RF Designer integrates seamlessly into the Virtuoso front-end and leverages Cadence’s patented electromagnetic analysis technology to accelerate and accommodate large designs found in today’s RFICs and System-on-Chip (SoC).

The Cadence RFIC solution provides an interactive link between system design and circuit design by integrating with Simulink from The MathWorks. In addition, Cadence has developed a toolbox for MATLAB that allows designers to access their simulation results in MATLAB for advanced visualization and post-processing.

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HOW WELL DO YOU KNOW THE INDUSTRY?

WWW.EMBEDDEDCOMMUNITY.COM

Cadence Design Systems Inc, San Jose, CA. (408) 943-1234. [www.cadence.com]. embeddedcommad_14v.indd 1

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ceo interview Steve Sanghi Microchip

While “Intel Inside” has been a huge marketing success, “Microchip Inside”—a tag line I just made up—has been a huge sales success.

While you may have one Intel processor inside your notebook computer, chances are you have dozens of Microchip microcontrollers around the house—in your washer, dryer, refrigerator, thermostat, even your kids’ toys. Microchip has long dominated the 4- and 8-bit MCU markets and is now a serious player in 16- and 32-bit nd devices as well. They’re also nicely profitable.

It wasn’t always so. When Steve Sanghi took er exploration ether your goal over the helm at Microchip 18 years ago, the speak directly company was so dysfunctional as to be moriical page, the ght resource. bund. As Sanghi tells it, “We had problems technology, in sales, financial issues, product roadmap ises and products sues, technology issues, quality, reliability ed and others.” Sanghi designed the Aggregate System—the subject of the 2006 book Driving Excellence—an enterprise-wide constant improvement plan that turned the company from a basket case into an industry leader.

Portable Design asked Sanghi about some companies providing solutions now of thelatest challenges Microchip is currently facing: exploration into products, technologies and companies. Whether your goal is to research the datasheet from a company, mp to a company's technical page, the goal of Get Connected is to put you in touchHow with the Whichever level ofof customers in doright youresource. support thousands gy, Get Connected will help you connect with the companies and products you arehorizontal searching for. markets? Why choose from among onnected 500 MCUs when I can use a single programmable one? Aren’t SoCs going to crowd dedicated MCUs off of the PC board? Sanghi had a ready answer to these and other questions. Suffice it to say he sees a large and growing role for Microchip MCUs in portable devices. Considering how consistently Microchip has been right, I wouldn’t recommend betting against the house.

End of Article Get Connected

with companies mentioned in this article. www.portabledesign.com/getconnected

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Portable Design: Microchip has the most extensive microcontroller catalog in the industry. How do you serve such an inher-

PORTABLE DESIGN

Get Connected with companies mentioned in this article.

ently horizontal market without fielding an army of FAEs? And how do you acquire the system-level design expertise to serve those numerous markets that you have targeted?

Sanghi: Microchip today is the only company that offers a complete, comprehensive, upgradable and compatible 8-, 16-, 32-bit microcontroller solution. Our product markets are very horizontal, it’s true—we serve over 60,000 customers around the world. How do we do that without fielding an army of FAEs? Well, we do field an army of FAEs! But by making the solution very compatible; by dealing with 500+ products from a common development platform; and by making the instruction set and the peripherals very compatible from one product to the other, we get significant economies of scale. Without that it [would just be] a patch-up solution from one product to the other. You would need an army that was much, much larger.

In terms of acquiring the expertise, early on when Microchip had smaller, lower-end 8-bit microcontroller solutions, it was easier. Most of the expertise we needed was just tips and tricks and teaching people various functions of the microcontroller. Today we do require lots of centers of expertise across specific functions like lighting, motor control and touch sense. So it’s a much harder job to acquire all that expertise.

Portable Design: With the addition of 16-bit devices, Microchip now offers a full range of MCUs. But isn’t 16 bits a bit of a niche market? Why not upgrade an 8-bit design directly to an inexpensive 32-bit controller, giving yourself some extra horsepower to allow for feature creep?

Sanghi: That’s the same question I used to hear 15 years ago: “Why not skip the 8-bit and go directly to 16 bits and have more performance available?” Working counterintuitive to that we built a billion-dollar, very successful business. I routinely get the same question now: “Why do 16 bits? Just go to 32 bits.”

First of all, 16 bits is not a niche market; it’s about a $3.5 to $4 billion market. Eight bits is about a $5.5 billion dollar market. Sixteen bits

is about a $4 billion market, and 32 bits is about $3.5 billion.

Next, what customers are looking for at the end of the day is to have a product that has 1) the throughput capability, and 2) the I/O bandwidth; our 16-bit products really have both. So many times we will engage with a customer who thinks they need a 32-bit solution, and we need a 32-bit bit solution just to get a visit. But once we engage and show them the capability of our 16-bit microcontrollers, more often than not they find that their application can be served with even more inexpensive 16-bit microcontrollers that can provide their needs with lower power, lower footprint, easier development tools, shorter time-to-market and other benefits.

Portable Design: Have you considered offering a programmable microcontroller family such as Cypress’ PSoC, or do you feel that there’s an appropriate PIC controller for any given design?

Sanghi: In our extensive portfolio of microcontrollers we do have several products with features and functionality like the PSoC, although we don’t really see them that way—and there is reasonable volume on those products.

However, in our 500+ product portfolio there is usually a more perfect product available, with hardware features that are exactly what the customer needs, hence removing the requirement for having the thing to be programmable.

Therefore the customer doesn’t have to architect that device exactly to his needs, because a better exact device is often available. So with a very narrow portfolio, maybe Cyprus needs a PSoC. With our extensive portfolio of products we can usually do the job with a more appropriate solution.

Portable Design: On portable devices with expensive board real estate, highly integrated SoCs with multiple controller cores are increasingly common. What’s the role for stand-alone controllers in portable designs?

Sanghi: In the hundreds of applications that Microchip serves, very often we find our 8- or 16-bit microcontrollers, some memory, some

analog chips around it, some sensors, capacitors, resistors and a battery. We don’t really find that hundreds of our applications require multiple cores or multiple microcontrollers. However when you go to higher-end applications— let’s say you’re trying to build a PDA device or higher-end device with huge capability—number one, microcontrollers are not to the point where they can serve as the main processor for those things; so in those kinds of applications often they will be either in power management or display driving or fixing a bug, with that tiny microcontroller providing some other mundane auxiliary functions and not being the main microcontroller. Otherwise, for hundreds and hundreds of applications where we are the main microcontroller, we don’t find that they need multiple cores.

Portable Design: Microcontrollers, while a critical part of any design, are only one component. How do the tools that you offer work with other tools in an integrated design flow?

Sanghi: Here again it is very rare for Microchip applications to have either an FPGA or a DSP or some other large processor on board requiring multiple kinds of tools that have to work with each other. Most times our devices are silicon on a chip; over the years we have called it “System on a PIC,” because most of our microcontrollers have extensive analog, power management and display driving capability, plus USB, Ethernet, sensing, all that kind of thing is available. Adding some more analog, resistors, capacitors and a battery often completes the system. So you do not need any other tools that have to work with our tools. We haven’t really seen that need.

Portable Design: Microcontrollers are becoming ubiquitous, adding intelligence to a wide range of devices. Where do you see the greatest growth over the next several years?

Sanghi: Microcontrollers have been ubiquitous for quite a long time. Our goal in life at the end of the day is to take any application that has power applied to it—either coming from

the wall or from a battery—if there is power applied to it, it should use a microcontroller, because microcontrollers can add features, functionality, performance, reliability or some sort of other added capability. The world is not quite there yet, so our job isn’t done. But we continue to add features and functionality to make that possible.

Where are we seeing a lot of the growth happening? One area is power management. Energy efficiency comes in multiple ways: either making things more green, using less power; the user interface, whether it’s touch sense or display driving; connectivity, whether USB, Ethernet, Internet—we’ve seen a lot of those connected applications. We’re also seeing things like efficient motor control, remote meter reading, and other energy-efficient applications like solar cells. A lot of the growth of microcontrollers is coming from such peripheral applications.

At the same time growth is also coming from your everyday washer or dryer or refrigerator now having multiple microcontrollers. In a refrigerator, one [may be] controlling the icemaker, one controlling the lighting, one making the motor more efficient. Maybe there’s a TV screen in the front door system so you can see the TV while cooking in the kitchen. It’s happening there, but it’s also happening in other peripheral areas that I talked about.

Portable Design: What changes can we expect to see in Microchip in the next three to five years?

Sanghi: We just crossed $1 billion in sales, and we have a blueprint in the company that takes us to $2 billion, with a fairly detailed plan in terms of revenue coming from what kinds of product lines, what additional stuff we need to acquire, what additional stuff we need to build.

We are well on our way toward executing that plan. So I think what you should see is really a dramatic march toward $2 billion. I would say the best of Microchip is yet to come.

JULY 2008

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The RTC Group is a media services company specializing in bringing companies and their products to a focused group of electronic and computer manufacturers. RTC is proud of its track record of blazing new trails in search of marketing value for our clients. Portable Design magazine is the newest addition to RTC Group’s collection of publications.

advertiser index Aptyc

17

www.aptyc.com

event calendar

ARM Developers’ Conference

7

www.arm.com/developersconference

08/26/08

Austin Semiconductor

4

www.austinsemiconductor.com

Battery Power 2008

11

www.batterypoweronline.com

Delkin Devices

45

www.delkin.com

EmbeddedCommunity.com

47

www.embeddedcommunity.com

Linx Technologies, Inc

47

www.linxtechnologies.com

Mentor Graphics

51

www.mentor.com

Micrel Semiconductor

2

www.micrel.com

San Francisco, CA www.digitalpower.darnell.com

Mouser Electronic

23

www.mouser.com

09/18/2008

National Semiconductor

52

www.national.com

Portable Design Conference & Exhibition

27

www.portabledesignconference.com

WAVEZero

45

www.wavezero.com

Real-Time & Embedded Computing Conference Montreal, QC www.rtecc.com/montreal2008 08/28/08

Real-Time & Embedded Computing Conference Ottawa, ON www.rtecc.com/ottawa2008 9/11/08

EDA Tech Forum Santa Clara, CA www.edatechforum.com 09/15-17/08

Digital Power Forum-DPF ‘08

NEW

Portable Design Conference & Exhibition Wyndham Hotel - San Jose, CA www.portabledesignconference.com 09/25/08

Real-Time & Embedded Computing Conference Phoenix, AZ www.rtecc.com/phoenix2008 10/01/08

EDA Tech Forum Boston, MA www.edatechforum.com 10/07-09/08

ARM Developers’ Conference Santa Clara, CA www.rtcgroup.com/arm/2008 If you wish to have your industry event listed, contact Sally Bixby with The RTC Group at sallyb@rtcgroup.com

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