ZKZ 64717 7-06 Bodo´sBodo´sPower Systems · designer to quickly optimize designs and monitor real-time system performance. "The expanding Di-POL product line offers flexibility,

Bodo´s Power SystemsBodo´s Power SystemsSystems Design Motion and Conversion July 2006

ZKZ 647177-06

Bodo´s Power SystemsBodo´s Power SystemsViewpoint Steam and Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2

Events . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2

News . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-6

Product of the MonthHighly Integrated Power over Ethernet Controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8

Guest EditorialMore than Just Power; By Peter Sontheimer, Tyco Electronics, Power Systems IC&P . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10

MarketThe Lennox Report; By Robert Lennox . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12

VIP Interview Digital Power on its Move, Interview with Ron Van Dell, President of Primarion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14-15

Cover Story Decentralized Motor Drive Applications; By Werner Obermaier, Tyco Electronics, Manager Product Marketing, Power Systems IC&P . . . .16-18

IGBTs Trench IGBTs Ensures Low VCE(sat); By Dr. Georges Tchouangue, Toshiba Electronics Europe (TEE) . . . . . . . . . . . . . . . . . . . . . . . . . . .20-22

Motion Control Cost-Effective Variable-Speed Motor Control; By Aengus Murray, International Rectifier . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24-25

Motion Control Smaller is Better for Motor Control Design; By Agustin Schuster, Silicon Laboratories Inc. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26-28

Power Management Optimizing Synchronous Buck Regulators; By Richard Chung, Member of Technical Staff, FAE, Fairchild Semiconductor . . . . . . . . . . . . . .30-34

Digital PowerDigitally Managed Power; By Todd Nelson, Product Marketing Manager, Linear Technology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36-39

Communication Power From Old Cars to High-Speed Home Networks; By Mark E. Hazen, Senior Technical Writer, Intellon Corporation . . . . . . . . . . . . . . . . . . . .40-42

Magnetic Components Ferrite Material for Energy-Meter Current Transformer- T36; By P. Mukherjee and S. Goswami, Epcos India . . . . . . . . . . . . . . . . . . . . . . . .44-45

MeasurementFiber-Optically Isolated Instrumentation; By Frank E. Peterkin, Benjamin M. Grady, Naval Surface Warfare Center, Dahlgren Virginia . . . .46-49

PCIM Innovations Snap Shots of Product Innovation at PCIM Nuremberg 2006 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .50-51

New Products . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .52-56

C O N T E N T S

1www.bodospower.com

Continual changes are the innovation stepsfor better results !Steam was yesterday. Wind is for free. Sogo and sail. That is the Engineeringapproach.

Industry has encouraged me to move aheadwith separate issues in July and August.Mailings will be in the first week of the monthin future. A printed magazine in your hand isone part of my overall information system.

A second part is my web site,www.bodospower.com,

with current News and Events. My site is upand available on demand for you - just stopby and pick out what you need. About threedays prior to mailing, the magazine becomesavailable on the web - read or download. I wish to serve your needs in a way bestsuited to you.

Power electronic designers, and their world,are a family that stays closer than in anyother industry. Having spent a quarter of acentury in design gives me the insight tostate this to my readers. And you are part ofthe process. Simply send me an e-mail so Ican include your thoughts.

To spread out good NEWS, get your friendsinto the loop. New qualified subscribers, andreregistered ones, have the chance to win aweek to come and stay in my Harbour ViewCondominium and as well as a barbecuechat with me during that time, in my housenear by. Every 2000th subscriber will be awinner. Winners will be announced in themagazine.

We all look forward to a relaxing vacation -but shut downs for a summer holiday are nolonger what they were. So the ARTICLESand NEWS will be important for you toreceive on a frequent base.

Actually, little in our world stays the same.Read about signal lines that deliver Power -as we see a big market coming in Powerover Ethernet. And in return, the power lineat the mains will be used as a communica-tion link in the future. Mark Hazen fromIntellon tells us what we will expect from thetechnology developed for what I will callCommunication over Power (CoP).

The cover story by Tyco describes progressin module design; presented by WernerObermaier. My friend Robert Lennox givesus his Report with up to date PowerSemiconductor info in the MARKET section.

IGBTs are the workhorse at higher voltageand Dr. George Tchouangue from Toshibaexplains how small IGBTs can help with theefficiency of plasma displays.

Digital control of Power becomes a moreand more respected area and deserves ourattention - Darnell will have its Conference inTexas on Digital Power. Take a look atEVENTS and check it on the web. And in theexclusive VIP INTERVIEW, Ron Van Dell,President Of Primarion, gives us an impres-sion of what is ahead in Digital Power.

IR and Silicon Labs have parts and solutionsin MOTION to talk about. IR addresses theconsumer market to improve efficiency in thehousehold. MEASUREMENTS in highpower applications need fiber-optics asexplained by Dahlgreen.

And for all of you that did not have a chanceto see Nuremberg and the PCIM show, afew impressions and a comprehensive snap-shot of products.

Now relax and see you again in August.

Best regards

Steam and PowerBodo´s Power SystemsBodo´s Power SystemsA Media

Katzbek 17aD-24235 Laboe, GermanyPhone: +49 4343 42 17 90Fax: +49 4343 42 17 [email protected]

Publishing EditorBodo Arlt, [email protected]

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Bodo´s Power Systems magazine is available for the following subscription charges:Annual charge (12 issues) is 150 €world wideSingle issue is 18 €[email protected]

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A Media and Bodos Power magazineassume and hereby disclaim any liability to any person for any loss ordamage by errors or omissions in thematerial contained herein regardless ofwhether such errors result from negligence accident or any other causewhatsoever.

E V E N T S

Power IntegrationDesign Seminars www.powerint.com

EPE-PEMC 2006Aug. 30-Sept.1, Portoroz, Slovenia,www.ro.feri.uni-mb.si/epe-pemc2006

Digital Power Forum (DPF '06) September 18-20, Richardson, Texas

www:darnell.com

H2ExpoOctober 25-26, Hamburg

www.h2expo

ELECTRONICA 2006Nov. 14 - 17, Munichwww.electronica.de

SPS/IPC/DRIVES 2006Nov. 28 - 30, Nuremberg

www.mesago.de

V I E W P O I N T

2 www.bodospower.com

STMicroelectronics announced theappointment of two new Corporate VicePresidents, Francois Guibert for Asia Pacificand Thierry Tingaud for the EmergingMarkets region.

Francois Guibert, currently CorporateVice President and General Manager of ST'sEmerging Markets Region, will be appointedto the position of Corporate Vice President,CEO Asia Pacific region, effective October 1,

2006. Guibert's appointment follows thedecision of Jean-Claude Marquet, the cur-rent Corporate Vice President of ST AsiaPacific, to retire in October 2006, after suc-cessfully managing the subsidiary since1995.

Under Marquet's leadership, theCompany's operations in the Asia Pacificcountries, including China, have seen sub-stantial growth over the past ten years.

Guibert, 53, is an ideal candidate for theposition of Corporate VP Asia Pacific, com-bining a successful management trackrecord and profound industry knowledge withkey contributions to ST's success in AsiaPacific. Succeeding Guibert's appointment,Thierry Tingaud, currently Vice PresidentSales and Marketing Europe forTelecommunications, will be promoted to theposition of Corporate VP and GeneralManager of ST's Emerging Markets Region,

effective July 1, 2006.

Taking the baton fromGuibert, Tingaud, 47 is fullyqualified to direct and driveST's Sales and Marketing oper-ations in Africa and the MiddleEast, India, Latin America,Russia and the EasternEuropean countries.

ST's Emerging Marketsregion covers a number ofbooming economies on fourcontinents, including the grow-ing giants of tomorrow - Brazil,India, and Russia.

www.st.com

STMicro Appoints Corporate VP's

The 2006 Digital Power Forum (DPF '06)will feature a significantly expanded techni-cal content, including an entire afternoondevoted to system-level issues when imple-menting digital power management solu-tions. And DPF '06 is adding an entirely newsecond track of papers focused on digitalenergy management and power manage-ment in enterprise-level installations andrelated digital equipment. The afternoon ses-sions related to system-level implementationof digital power management are beingorganized in cooperation with the PMBusOrganization.

The new track on digital energy manage-ment at the facilities level is being organizedin cooperation with AMD and the U.S.Environmental Protection Agency ENERGYSTAR Program.

"Adding a second track of papers to theDigital Power Forum is a huge step. It willenable us to reach a larger and morediverse audience. The afternoon sessionsdevoted to systemlevel issues will furtherstrengthen what has become the industry'sleading conference on this rapidly emergingarea of technology." stated Jeff Shepard,President of Darnell Group.

"DPF '06 will be a showcase for the latestdevelopments in digital energy managementin mission-critical facilities, as well as sys-tem-level power management and powerconversion products and technologies."

Reflecting this broader scope, DPF '06has an expanded Advisory Committeeincluding representatives from AMD, AnalogDevices, Artesyn, Astec, Coldwatt, EnergyStar, Fairchild Semiconductor, IBM, Intel,

International Rectifier, Power-One,Primarion, STMicroelectronics, TexasInstruments, Tyco Electronics and ZilkerLabs.

Darnell Group and PowerPulse.Net arethe organizers of DPF '06 September 18th to20th Richardson Texas. This focused three-day international conference will serve anaudience of decision makers who are inter-ested in learning about and contributing tothe latest practical advancements related tothe use of digital power control techniques inelectronic systems and in power converters,and digital energy management and powermanagement in enterprise-level installationsand related digital equipment.

www.darnell.com/digitalpower/

Digital Power Forum Francois Guibert Thierry Tingaud

N E W S


Vishay is pleased to announce that it hasbeen selected to receive DelphiCorporation's 2006 Pinnacle Award. Theaward from Delphi, a world leader in mobileelectronics and transportation componentsand systems technology, recognizes suppli-ers primarily for their outstanding quality per-

formance or quality improvement. Vishay isone of the world's largest manufacturers ofdiscrete semiconductors and passive elec-tronic components. The automotive industryis one of the many industries worldwide inwhich Vishay products are used.

As a Pinnacle Award recipient, Vishayhas met or exceeded Delphi's requirementsfor recognition.

http://www.vishay.com.

Pinnacle Award from Delphi

Primarion, a mixed-signal semiconductorcompany that provides digital controllers forpower solutions, announced the addition ofthe dual-phase PX7520 to the Primarion Di-POL product family of fully programmabledigital power conversion and power man-agement ICs.

Priced competitively with existing analogsolutions, the all-digital Primarion PX7520 isa dual-phase power conversion and powermanagement IC for non-isolated DC/DCconverters in telecom, datacom, computingand storage markets. This highly config-urable digital control IC utilizes PMBus andon-chip non-volatile memory (NVM) forextensive user-friendly control and real-timesystem monitoring.

"The largest and fastest-growing portionof the worldwide digital power IC market isexpected to be the power conversion andpower management area targeted byPrimarion with the Di-POL product line," saidJeff Shepard, President of Darnell Group."Our latest analysis projects that segmentwill grow from $14 million in sales this yearto almost $400 million by 2011 - a five-yeargrowth rate of 95 percent per year."

The PX7520 utilizes digital technology toimplement all control functions, providing theultimate in adaptable, stable and flexiblesolutions at an increased output load. Byincorporating an industry standard I2CPMBus serial interface for control and moni-toring, Primarion enables the power supply

designer to quickly optimize designs andmonitor real-time system performance.

"The expanding Di-POL product lineoffers flexibility, adaptability and communica-tion interface in a single-chip power solutionpossible only with digital technology - butwith the same cost and increased densitycompared to the closest analog solution,"said Deepak Savadatti, VP of marketing forPrimarion.

www.primarion.com

Programmable Digital Power

Datatronic, manufacture of advancedmagnetic components for hi-rel mil-aero,medical, commercial and industrial applica-tions, has named Deltron Electronics Plc ofthe United Kingdom as its authorized distrib-utor for Europe.

Founded in 1971, Datatronic is a HongKong based company with operations in theU.S., Hong Kong and China. The compa-ny's magnetic components are found in awide range of products, ranging from lead-ing-edge aircraft to portable electronic defib-rillators to computers to telecom devices to

appliances and more.

The company's Datatronics Romolandbusiness unit, which is located in Romoland,CA, produces magnetic components forhigh-rel aerospace, life critical medical sys-tems and other mission critical applications.Co-located in the same facility is DatatronicsDistribution, Inc., which manufactures mag-netics components developed for commer-cial and industrial applications, such aspower supplies, modems, industrial controlsand more.

Deltron will represent Datatronic in allcountries in Europe, with the exception ofFrance. Founded in 1991, the companyspecializes in electromechanical and mag-netic components.

www.datatronics.com

Datatronic Names Deltron as Rep

Cree announced that its Japanese dis-tributor, Sumitomo Corporation, has agreedto purchase USD180 million of Cree's light-emitting diode (LED) and wafer productsduring Cree's fiscal year ending June 2007,subject to end-customer demand and otherterms and conditions. The USD180 millionrepresents approximately a 10-percent

increase over Cree's current estimate for fis-cal 2006 sales to Sumitomo. Both compa-nies anticipate that purchases will be madeacross Cree's full line of wafer and LED chipproducts.

Sumitomo made the purchase commit-ment pursuant to its existing distributorship

agreement with Cree. Cree previouslyannounced that sales to Japan in fiscal 2006were running below the original plan for theyear.

www.cree.com

USD180 Million Agreement

N E W S


P R O D U C T O F T H E M O N T H

Silicon Laboratories announced theindustry’s most highly integrated,IEEE 802.3af compliant, Power

over Ethernet (PoE) controller for powereddevice (PD) applications. The Si3400 is theonly PD controller to integrate on-chip diodebridges, a transient surge suppressor and aswitching regulator field effect transistor(FET). The Si3400 controller’s unprecedent-ed level of integration simplifies PoE designefforts by dramatically reducing the total billof materials (BOM), printed circuit board(PCB) area and time to market.

Targeted at wireless access points (WAP),voice over IP (VoIP) phones, radio frequencyidentification (RFID) tag readers, point-of-sale terminals, security systems and cam-eras, the Si3400 eliminates up to 25 externalcomponents compared to competing solu-tions. This reduces the PCB footprint by 30to 50 percent and the total BOM by as muchas $1.50. Fewer external componentsimprove overall product reliability and simplifythe supply chain for customers. The Si3400enables PoE system designers to focus onsystem-level product differentiation and cus-tomization rather than spending valuabletime and resources on external componentsand challenging design issues, such as ana-log layout or meeting radiated emissions

specifications.

“The Si3400 represents the first product inour Power over Ethernet family,” said DaveBresemann, vice president of SiliconLaboratories. “Our extensive high-voltagedesign experience has enabled us to solveseveral board-level analog design chal-lenges, which will help lower costs and accel-erate the adoption of Power over Ethernettechnology in a wide array of end products.”

Silicon Laboratories achieves unparalleledintegration with the Si3400 by leveraginghigh-voltage and mixed-signal design expert-ise to deliver a unique, feature-rich and ver-satile architecture that is fully compliant withIEEE 802.3af, while adding features beyondthe standard’s base requirements. Forexample, with direct access to the line sidevoltages from the Ethernet cable, the inte-grated diode bridges enable a proprietaryearly power loss indicator, which providesadequate time to save operating and statusinformation before safely shutting down thepowered device. The diode bridges alsoallow a direct connection to the RJ-45 con-nector, which minimizes the PCB tracelengths between the connector and theSi3400. This helps limit radiated emissions,speeding certification required by PoE prod-

ucts. In addition, the integrated transientsuppressor activates protection circuitrywhen high voltages are detected, improvingoverall device robustness and reliability.

The Si3400 controller includes a completePD interface with programmable classifica-tion and detection signature circuitry, aswitching regulator controller, dual current-limited hot swap switch, comprehensive pro-tection circuitry including thermal shutdowncapability and support for both non-isolatedand isolated applications. The Si3400 hasbeen designed to operate seamlessly withboth 802.3af compliant Power SourcingEquipment (PSE) and pre-standard (legacy)PSEs that do not comply with the standard’sinrush current limits.

Pricing for the Si3400 begins at $2.48 inquantities of 10K. Packaged in a lead-free(RoHS compliant), 5 x 5 mm, 20-pin QFN,samples are available now, and production isscheduled for Q3 2006. An engineeringevaluation board (Si3400-EVB) is also avail-able now and will be followed by a completeEthernet system evaluation kit in August.

www.silabs.com

Highly Integrated Power overEthernet Controller


Today more than ever, successin the business of electronicsubsystems, particularly power

modules, hinges on choosing the rightstrategy. It must be sustainable, feasibleand dynamic in its tactical implementa-tion. If an enterprise’s strategic course iswell-charted, it will be responsive to themarket.

This is especially important becausemarkets for applications requiring powermodules are constantly changing andgrowing. Today we are seeing applica-tions in distributed power generationwhich were not in evidence a decadeago. Energy security is a powerful driverfor applications such as fossil-fueledgenerators, solar-power or fuel-cellinverters. Power module vendors arenow challenged to deliver products thatnot only serve their intended function,but also help customers boost theirapplications’ efficiency. The key to doingthis is selecting the right componentsand module layouts to make the cus-tomer’s application easy to implement.

High voltage power has arrived in auto-mobiles, making inroads into a market inwhich Hybrid Electric Vehicles (HEV) andfuel-cell vehicles have figured so far asniche applications at best. With hybrid pro-duction models hitting the streets, the mar-ket for power electronics and power mod-ules is gaining the momentum it takes to fos-ter products. To plant a footprint in this mar-ket, component providers must offer morethan merely an Electronic ManufacturingService (EMS) for power modules. Theymust solve the problems associated withenergy storage protection, distribution andconversion. Plenty of know-how is available;strategic alliances help make it accessible.Yesterday it was the matter of who will com-mit; today the issue is, who has what it takesto pull it off?

In traditional markets such as motioncontrol, it is safe to say that power modulesare a commodity in many applications.Although production has yet to reach the

quantities of other components such asmemory products, the market’s call for asecond source is loud and clear. Differentsources offer new-generation higher powerstandard modules at 17-mm height. Dual-sourced MiniSKiiP and flowPIM modules areavailable on the market. We can point to agreat record of achievement in these fields,with satisfied customers who were able todispel the difficulty of single sourcing fortheir high-runner products.

Nonetheless, a single-source product is asensible solution when the focus is on inno-vative features. Differentiation throughenhanced functionality and packing densityenables the innovative partner to position hisproducts. Often the simple ideas prevail. Inthe past, it was difficult to implement anapplication in bookshelf format for example.With their skillfully engineered pin connec-tion, flow90 modules enable a power moduleto be wave-soldered together with otherthrough-hole components.

Some customer requirements areeven more demanding, posing specialchallenges for a power module. Forexample, servo drives require utmostrobustness regarding vibration stress,long life-time and use in hard potting.The module flyerIPM offers innovativeanswers to most of these questions.This product shines with an integrateddriver stage, power supply and manyprotective functions for high packingdensity.

An end-to-end provider of powermodules has a comprehensive productroad map. This means he offers a fullrange of modules across all standardpower classes. In the past three years,Tyco Electronics has extended its offer-ing to incorporate higher power classes,among other products, thereby creatinga persuasive range. The latest additionis flowPHASE 3, a half bridge for indus-trial applications with currents ranging to450 A at 1200 V.

Ensuring uniform packaging for halfbridges and full bridges, rectifier modulesnow come in industry-standard, 17mm-highhousings. Here too, customers had a voicein formulating the product strategy.

Creating and exploiting synergies is vitalin all these efforts. It is not always necessaryto develop modules and applications anewto roll out products. Technologies developedfor industrial use benefit automotive applica-tions for instance. The demand for powercircuitry in all areas of our lives is great andgrowing fast; witness the mega-trends ofmobility, green environment and unlimitedcommunication capability. I hope that play-ers are able to plan with foresight and pro-vide the necessary resources in terms ofboth intellectual property and material flowand supply. Players who listen carefully towhat the market is saying and remain flexi-ble will be well-prepared to master the chal-lenges of today and tomorrow.

G U E S T E D I T O R I A L

More than Just PowerBy Peter Sontheimer, Tyco Electronics, Power Systems IC&P

www.em.tycoelectronics.com


GENERALDell will dou-

ble its Indianemployees to 20000 including fora manufacturingsite as its busi-ness modelbased on lowprices via directsales is beingweakened byprice competition

from Acer, Lenovo among others and lack ofgood customer service. Dell is increasingpurchases from Taiwan suppliers most ofwhom produce in China and after years ofresistance plans to open two pilot retailstores though no products will be in stockand all purchases have to be made electron-ically. In recent years the company hasopened about 160 kiosks in US shoppingcenters but again no direct sales, only dis-play of products.

SEMICONDUCTORS According to the WSTS global semicon-

ductor sales in April increased 8.1% overprior year but declined 0.4% sequentially to$ 19.600 B. Asia-Pacific led with a 14.4%growth over last year followed by theAmericas' 11.4% and Japan's 1.4% whileEurope declined 2.7% to $ 3.232 B, -0.2%sequentially but in Euros gained 5.2% overprior year though declining 0.5% sequentiallydue ainly to weaker MPU sales.

SICAS IC fab capacity and utilizationstatistics for the first quarter of 2006 showeda decline in utilization from 91.8% in the pre-ceding quarter to 89.5% explained in part byseasonal trends. MOS utilization droppedfrom 92.6% to 90.2% while Bipolar declinedfrom 78.9% to 77.4%. Nevertheless, capaci-ty is likely to remain constraint.

A study by the WSTS of the 2005 worlddiscrete semiconductor market estimatessales of $ 10.78 B, down from 2004, withpower transistors accounting for $ 7.725 B(including MOSFETS $ 4.160 B, IGBTs $1.444 B, bipolar $ 1.142 B, RF $ 841 M)while rectifiers contributed $ 2.3 B ($ 1.2 Bto 3A) and thyristors $ 730 M ($ 600 M to55A). Japan consumed $ 2 B of discretes,the rest of Asia $ 3.5 B, Europe $ 1.3 B andthe US $ 900 M. The current year shouldsee a 1% market decline followed by a 7%growth in 2007. According to DataquestToshiba was the industry leader in 2004 fol-lowed by ST, Renesas and Rohm, all withsales of from $ 1.06 B to $ 1.3 B. Fairchild,Philips, Infineon and Vishay had sales rang-ing from $ 900 M to $ 965 M while IRreached $ 867 M and Mitsubishi $ 707 Mwith little change in 2005 rankings xpected.

AMD is a founding member with IBM, HPand Sun Microsystems, of "The Green Grid"designed to help reduce electricity consump-tion at data centers, is setting up in Dresdena new development center headed by ChrisSchläger. It is aimed at optimizing proces-sors and modern operating systems. Alsoannounced was its first dual-core processorfor laptops due out next year and, as previ-ously indicated, will expand its fab capacityin Dresden with an investment of $ 2.5 Bover the next three years including movingfrom 200 mm to 300 mm wafers and to 65nm processes.

STMicroelectronics expects a two-digitgrowth rate this year encouraged by a firstquarter increase of 13.5% after a ratherstagnant 2005 of $ 8.88 B sales.Investments of $ 1.8 B are foreseen thisyear though continuing outsourcing of certainproducts such as to TSMC via the "Crolles2" alliance. ST is open to new alliances suchas were made with Freescale in automotive

and Hynix in NOR flash with industry re-composition rather than consolidation a pos-sibility, so ST's Philippe Geyres. Japan'ssemiconductor industry has been goingthrough restructuring for some time. Thefirm's Philippe Dauvin claims that Europelast year accounted for 27% of the world'selectronics design activities, behind the US'35% ut ahead of Japan's 23% and Asia-Pacific's 15%.

Texas Instruments is evaluating CMOSRF technology of recently acquired Chipconwith a possibility of integrating into DSPdevices for the mobile phone market and isin talks with NEC in the same market. Othercooperations include cost-effective PCI-SIGconform solutions based on Altera's IP andTI's X101100-PHY and with MercuryComputer in an Advanced Mezzanine ard forWiMax.

Freescale increased first quarter sales3.4% sequentially to $ 1.53 B, sees currentquarter rather flat, will supply CMOS on 300mm and 65 nm processes this year. The firmemploys 4600 in EMEA with 20% of salesgoing via distribution. Bill Bradley has beennamed Sr. VP world-ide sales.

About 37% of Sharp's semiconductorbusiness is in Europe. Now, for the first time,a European, Hans Kleis, becomes GroupDeputy GM-International Business Groupresponsible for the firm's total activities inEurope replacing Daisuke Koshima. InFrance Sharp does about € 300 M business.Sharp's revenue in Europe increased 0%last fiscal year to about 35% of total corpo-rate sales.

[email protected]

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M A R K E T


V I P I N T E R V I E W

Bodo Arlt: What end markets will drivedigital power management?Ron Van Dell: The high-end servers andgraphic cards are the main products thathave started taking advantage of the benefitsof digital power. We expect the next area forgrowth will be data communication with itspoint-of-load (POL) structures for variousvoltages to serve.

Bodo Arlt: What is Primarion’s positionbesides teaming up with LTC?Ron Van Dell: Linear Technology is the latest strategic partner to offer multiplesourcing for our all-digital-solutions - LTC isfocused on our emerging digital POL (Di-POL TM) products; Intersil is our second-source partner for our digital multi-phase power solution that changes the land-scape of processor power.

BodoArlt: What are the technologies thatoffer innovation for leadership?Ron Van Dell: Innovation is based ondesign. The Primarion controller is a truedigital core engine compacted to reach pricetargets and improve on conventional solu-tions.

Bodo Arlt: Is it more in silicon, or is it part ofsmart software for controllers?Ron Van Dell: We are talking about a morehardwired, state-of-the-art machine that isnot a DSP.

Bodo Arlt: What makes Primarion differentfrom traditional analog suppliers?Ron Van Dell: The true digital controller withthe PWM as a digital loop is our main com-petitive differentiator in comparison to analogsolutions.

Bodo Arlt: What makes Primarion differentfrom traditional digital suppliers?Ron Van Dell: Primarion is not a traditionaldigital supplier that serves the customer witha standard chipset. We have multiplesources of discretes to combine with ourcontroller to take full advantage of the valueof digital technology.

Bodo Arlt: How much is Primarion involvedin the digital feedback loop of power convert-ers?Ron Van Dell: Primarion has a 100-percentdigital control loop.

Bodo Arlt: How much is Primarion involvedin digitally controlled power conversion?Ron Van Dell: In the conversion space, wealso have a 100-percent digital solution inplace.

Bodo Arlt: What will be the target date tointroduce the first products?Ron Van Dell: We introduced the VR prod-ucts for servers and graphic cards in 2003,with volume ramp-up in 2004. The POLproducts were introduced in late 2005 andwill continue to ramp up throughout 2006.

Bodo Arlt: I have seen during my time asan engineer the conversion from linear toSMPS power supplies. Do you expect a sim-ilar transition into the market?Ron Van Dell: The transition will be some-what similar, but it is still a PWM conversion.The change takes place inside the controllerchip.

Bodo Arlt: Tradition is always resistant tonew technology. What is your feeling to over-come this?Ron Van Dell: We will not see an easy tran-sition for power analog designers. They will

Digital Power on its MoveInterview on Digital Power with Ron Van Dell,

CEO & President of PrimarionBy Bodo Arlt, Editor BPSD

Ron Van Dell, CEO & President, Primarion

Ron Van Dell, CEO and president of Primarion, Corp., joined the company in 2004 fromLegerity, a privately held communications semiconductor company with about $100M inannual sales, where he served as President and CEO. During his tenure, the companyovercame the worst-ever downturn in its primary market to become the clear worldleader in chipsets for wire line voice access -- positioned to dominate the transition fromtraditional telephony to VoIP.

Previously, Van Dell served as GM for Dell Computer’s Dimension product line withresponsibility for worldwide home and small business desktop PCs. Under his leadership,the Dimension line grew at twice the overall market rate, exceeding $6 billion in annualsales, and became a cornerstone of Dell’s aggressive international expansion.

At Harris Semiconductor (now Intersil Corporation) as VP-GM of the CommunicationProducts Business, Van Dell provided the leadership for establishing the IEEE 802.11bstandard, as well as for the rise of PRISM chipsets to a dominant position within thehigh-speed wireless LAN marketplace. In an earlier role as VP-GM of WorldwideMarketing and Sales, he focused on major growth in discrete power and power manage-ment.


feel less comfortable than the DSP design-ers, who typically have to deal with a lot ofprogramming. They analog designers willprefer to stay in their world, which makes itmuch easier.

Bodo Arlt: What will be the year that digitalpower will dominate the market (about80%)?Ron Van Dell: The change to digital powerwill occur at different times in the variousapplication segments. The first change, andone that we are already witnessing, is inservers. Graphic cards will be next, and datacommunication will take a few years.

Bodo Arlt: Who are your competitors youbelieve will stimulate the race for leader-ship?Ron Van Dell: Volterra is the only competi-tion that is currently shipping product. Thisproduct is a closed (proprietary) solutioncompared to ours, which is open to discretesfrom multiple vendors.

Bodo Arlt: Are you ready for Electronica inNovember?Ron Van Dell: We want to attend focusedshows that directly target our power designaudience. Electronica may be too broad aplatform for Primarion, but we plan to have apresence at several power industry events inthe coming months.

Bodo Arlt: Thank you Ron for the time andwe look forward to a successful future fordigital power.

Van Dell also held previous internationalmanagement positions in the U.S. and inEurope at Groupe Schneider, Square DCompany and General Electric. He current-ly serves on the Board of Directors ofSynaptics, Inc.

Van Dell earned a BS with honors inElectrical Engineering from MichiganTechnological University. He is a memberof the MTU President’s Club and serves onthe Industrial Advisory Board for theCollege of Engineering at MTU.

www.primarion.comTyco Electronics Power Systems Finsinger Feld 1 D - 85521 Ottobrunn, Germany Tel.: +49 (0)89 6089 830 Fax: +49 (0)89 6089 833 [email protected]

The Solution for 90° Construction –flow90PIM 1 & 2

Currently more and more motor drive inverters require the heatsink to be in an upright position in respect to thePCB (90° mounting angle). The new configuration of TycoElectronics’ flow90PIM is the ideal solution providing thefollowing benefits in addition to the standard Power Modulecharacteristics:

W 90° position for wave soldering together with standard through hole components

W On board clearance and creepage for 1200V systemsW Latest trench field stop IGBT technologyW Clip in: The reliable interconnection between PCB

and moduleW Alternative heatsink mounting; screw or clip-on

Features:W 3 phase rectifier bridge + IGBT inverter + BRC and NTCW Up to 75A/600V and 35A/1200VW Up to 14kW electrical

output power

www.bodospower.com

The article will illuminate the rea-sons for the shift towards decen-tralized motor drives in factory

automation, the special requisitions thisimplicates for the drive as well as its powersection. It shows on a real example how toachieve these additional demands with ahighly integrated Power Module from TycoElectronics.

Decentralized Motor Drives gainMomentum

The complexity of tasks to be handled infactories is increasing from factory genera-tion to generation. Modern factories in theautomotive or packaging industry for exam-ple are using hundreds of variable speeddrives to manage the material flow and theactual production processes like car bodyassembly, welding and varnishing or bottlecleaning, filling and labeling respectively. Inmost factories up to now a centralizedapproach has been implemented, shown infigure 1.

Thereby, all actuators (motors) havebeen routed with dedicated power and sig-nal cables like a cobweb from a central cabi-net containing the frequency inverters. Eventhough being the right choice in the past, itdoes not cost effectively accommodatetoday’s increasing amount of installed vari-

able speed drives in newly build factories. Inaddition, the demand for achieving full con-trol over the complete production processincluding peripheral tasks at remote placesfurther increases the cost of this cobwebkind of system setup.

The further the drives are away from thecabinet with its centralized inverters thehigher the cost for cabling. The more drivesare installed in a factory the higher theamount of space occupied by cabinets.Furthermore, the more complicated a cob-web kind of wiring becomes the higher theresulting installation and system costs.

The decentralized motor drive approachis the answer to this changed situation withits new system split and the relocation of theinverter section away from the cabinet intothe motor, as shown in figure 2. This newarrangement enables the use of a commonpower and control cable wiring like themains grid. This results in dramatic reductionof cables that have to be run. Moreover, asignificant simplification in cabling isachieved as only two different wires, one forthe power and one for the control circuit,have to be routed. This enables local non-specialized electrician to prepare the instal-lation at reduced cost.

Some of the savings due to the reducedcabling effort will be consumed by the addi-

tional requirements the inverter has to fulfillwhile being relocated from the cabinet intothe motor. A study of system cost conductedby the Institute for Machine Tools andEconomics at the Technical University ofMunich/Germany shows that for machiningcenters a distributed approach while increas-ing material cost by 8 %, the assembly costare cut by 2/3. This results in an over allcost reduction of almost 30 %. The cost sav-ing is even more impressive for transferlines where traditionally the distances andtherefore the cabling efforts are higher. Herethe material costs are decreased by about30 % due to the reduced amount of cablesand the elimination of cabinets. In addition,the assembly costs are lowered by 4/5 dueto the easier interface which results in totalcost reduction of almost 70 %. This explainsthe triumphal procession of decentralizeddrives into the factory setups.

Decentralized Drives set New InverterRequirements

The move of the inverter away from thecabinet into the motor introduces new requi-sites to the inverter design. One of the mostdemanding ones is the thermal manage-ment. In the cabinet the inverter wasinstalled in a rather friendly environment withno particular demands regarding ingressprotection generally classified as IPXX. Themotor itself will be installed somewhere inthe production line close to the goods to beprocessed which can be heavy machinerylike car bodies or fragile goods like foot.Because of this the motor together with itsinverter in case of a decentralized drive sys-tem have to be washable with all sorts ofdetergents and therefore IP65 protected. Inan IP65 protected system the dissipatedpower of all components can only be con-ducted to the outside world via the surfaceof the system, mainly the heat sink.

C O V E R S T O R Y

Decentralized Motor DriveApplications

New Requirements regarding the Drive System is raisedThe increasing demand for decentralized motor drives in factory automation makes thenew requirements for the implemented inverters in general and for the power section in

particular more and more evident.

By Werner Obermaier, Tyco Electronics, Manager Product Marketing, Power Systems IC&P


Figure 1: Motor installation with CentralizedInverter

Figure 2: Decentralized (Cabinetless )System

17www.bodospower.com

Therefore for an inverter used in a decentral-ized drive it is essential that power dissipa-tion is reduced and all power dissipatingcomponents are somehow connected to theheat sink. This is required to keep the over alltemperature low and avoid hot spots in thesystem to ensure overall system reliability.

In addition, the inverter has to be small toadmit compact motor designs and highinstallation density, which enables complexsequences at minimum floor space whichalso leads to cost savings. Examples can befound in the packaging industry. This com-pact design makes an optimum thermalmanagement even more important due tothe limited surface area of the system. It alsorequires an intelligent system split to mini-mize interconnections between the powersection, the energy storage, and the controlboard of the inverter to minimize the totalsystem space.

With the movement of the inverter intothe motor also the demand for the mechani-cal ruggedness of the electronic system hasincreased. The inverter with its electronicswill now see the same mechanical stress asthe motor. This can vary from micro vibra-tions due to the finite stiffness of the motorfitting during acceleration and braking tomacro vibrations when the drive is part ofthe moving system. Examples for this aretransportation systems like cranes, elevatorsor electronic vehicles. Due to resonanteffects and amplifications by non-linearstructures an acceleration of the motor-inverter system of 5 g (earth gravitation) canresult in accelerations of 50 g or higherinside the system. Therefore, special carehas to be taken to ensure a particular robustdesign regarding shock and vibrations.

Moreover, many of the decentralizedmotors will be used in highly demanding sys-tems with high dynamic output load require-ments like servo drives to improve systemthroughput and overall performance. Thus,high dynamic output load capability togetherwith accurate system parameter sensingshould be implemented in the decentralizeddrive system.

The additional requirements for theinverter of a decentralized drive can be sum-marized to following points:Improved thermal management to be func-tional in a fully encapsulated environment(IP65)

# Ultra compact, highly integrated design# High shock and vibration capability # High dynamic output load capability

Highly Integrated Intelligent PowerModule enables Decentralized Drives

For the former described requirementsa new system split for the inverter is rea-sonable. Because of the encapsulation ofthe system all major power dissipatingcomponents should be mounted onto theheat sink. Due to space constrains theinterfacing between the sections shouldbe kept to a minimum. Having this inmind, the optimum system split will resultin a power section, a capacitor bank sec-tion and a control board. The power sec-tion should include the drive circuit, cur-rent sense resistors, drive and interfacepower supply, all with access to the heatsink. The capacitor bank section mayinclude an input rectifier dependent on thesystem setup (DC or AC bus).

The power section namely a highlyintegrated intelligent Power Module pro-vides the enabling element for thesedecentralized drives. Figure 3 shows thePower Module and picture 4 the circuitdiagram. The P520 from Tyco Electronicsincorporates a 25 A 1200 V IGBTs sixpacktogether with freewheeling diodes and 3current sense resistor placed in the outputphases for accurate current sensing on aDCB substrate, similar to a standardPower Module. This Power Module is sur-rounded by the isolated gate drivers, thecircuit for the 3-phase current, the tem-perature and the DC bus voltage sensingas well as a high voltage DC/DC powersupply. This DC/DC converter provides allthe required isolated supplies for the gatedrivers and the logic interfaces directlyfrom the 600 V bus. The inverter DCB issoldered to the baseplate to ensure opti-mum heat transfer. All the surroundingcomponents are placed on a FR4 boardand glued to the baseplate using thermal-ly conductive glue. This provides a goodthermal heat transfer for the surroundingdevices as well, enabling the use of opti-cal components such as optocoupler, gatedriver and isolation amplifier.

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Figure 3: P520 Power Module

Additionally a ceramic DC link capacitorof 720 nF is implemented on the P520 FR4board. This capacitor is placed close to theinverter 6 pack, capable to support theswitching current to minimize EMI genera-tion, and to relax the requirement for theexternal bulk capacitor. With this approachthe bulk capacitor can be placed furtheraway form the inverter switches, providing ahigher degree of design flexibility.

The system split minimizes the requiredamount of power interconnections to onlyfive, two for the DC link input and 3 for themotor phases. This, together with the 6 gatedrive signals, and the 6 sense signals,results in a minimum amount of interface sig-nals, reducing cost and space for intercon-nections. All the components on the PowerModule are fully enclosed by a high isolationpotting material which protects the compo-nents and bond wires. Due to this the wholepower section can be realized on a footprintof only 99 x 97 mm. Therefore it can beused even for small drives.

For improved shock and vibration capa-bility only small and light components areused. The DC link capacitor for example isbuild of six 120 nF 1000 V ceramic capaci-tors to minimize the weight. The largest com-

ponent used in the Power Module is thepower supply transformer which has beenkept to only 15 x 15 mm by using 500 kHzswitching frequency. The interconnectionbetween the DCB and the FR4 board is pro-vided by wire bonding, as shown in figure 5.This provides highest reliability at minimumweight ensuring maximum shock and vibra-tion capability. The whole Power Module isable to withstand shock and vibration forcesof up to 80 g.

The required dynamic loadcapability is achieved by theuse of a 3 mm thick copperbaseplate. In conjunction witha 0,38 mm thin DCB substrateit provides outstanding thermalperformance. Compared to astandard Power Module with-out baseplate the heat rise fora given increase in load istherefore reduced. In the P520design the baseplate is notonly underneath the substratebut also covering the muchlarger area of the PCB (figure6). This provides additionalthermal capacity which further reduces theheat rise for short load cycles; often seen in

servo drive applications. Figure 7 shows thecomparison of the P520 and a standardPower Module without baseplate, using thesame semiconductors. The measurement isdone for a 1 sec. pulse providing 40 Wpower dissipation. The Power Module with-out base plate reaches a temperature of 122°C while the IGBT of the P520 only reaches108 °C. This reduction in temperaturechange enhances the lifetime for the P520according to Coffin-Manson by about five tosix times.

SummaryThe growing trend of decentralized drives

in factory automation demands for a newkind of inverter with widely improved per-formance. To achieve these requirements anovel Power Module is needed, which incor-porates a standard module together with allthe drive, sense and interface functions on avery small footprint featuring superior ther-mal characteristics. The newly introducedP520 from Tyco Electronics is the first repre-sentative of this new kind of Power Moduleavailable for the open market.

References [1] The New Built-In Servo drive ´Posmo Si´- an alternative approach to Mechatronics(CIPS June 2000), Dipl.-Ing. (univ.)Sebastian Raith, Siemens AG Erlangen,Germany[2] Advanced integration for mechatronicdrive systems (PCIM-Europe 2001),Sebastian Raith, Torsten Franke, SiemensAutomation & Drives, Erlangen, Germany[3] Motor Integrated IPM-Solution for ServoDrive Applications (PCIM-China 2006),Michael Frisch, Tyco Electronics PowerSystems, Germany

www.em.tycoelectronics.com


C O V E R S T O R Y

Figure 4: P520 schematic

Figure 5: P520 Interconnections

Figure 7: Comparison of P520 (Tj520) with standard powermodule without baseplate and identical chipset (Tj360)

Figure 6: Module Structure

High clarity and brightness at largescreen sizes are among the keyadvantages of PDP technology.

However, market success also demandsacceptable energy efficiency, as excessiveheat dissipation adversely impacts upon reli-ability as well as operating costs. One ener-gy saving technique that is used in PDPdesign is to implement an energy recoverycircuit (ERC) in conjunction with the sustaincircuitry that illuminates each cell in the PDPmatrix once per full picture refresh cycle.

During the sustain discharge, very highpeak currents occur. The magnitudedepends on factors including the number ofcells illuminated with any single sustainpulse, which in turn is influenced by the sizeof the panel itself. However, for a modernPDP of around 42-inches or larger, peaksustain currents above 100A can beachieved. Since the PDP presents a capaci-tive load of several tens of nanofarads, anERC is implemented to recover the reactivepower that would otherwise be lost. This canbe as high as 4-500W in a 42-inch display.

Switching Characteristics and EfficiencyHowever, the sustain and recovery cir-

cuits must themselves be designed to min-imise losses, as resistive losses contributedby conduction and switching inefficiencies inthe power transistors of these circuits cancontribute significantly to overall power con-sumption. Hence, when designing the sus-tain and ERC networks, engineers need apower switching solution that delivers anoptimal combination of high peak currenthandling capability and high voltage opera-tion at 300V or higher typical in PDP appli-cations, with on-state and switching losses.

MOSFET, or IGBTThese requirements pitch PDP designers

into the thick of the territorial battle betweenpower MOSFETs and IGBTs. The powerMOSFET typically displays good high fre-quency characteristics, high peak currentcapability and easy gate drive requirements.On the other hand, on-losses (conductionlosses) increase with voltage rating, firstlydue to the relationship between Rds(on) andthe drain-source blocking voltage (VDSS),and secondly due to ID2 (where ID is thedrain current). Trench technology hasallowed MOSFETs to improve RDS(ON), butthe voltages present in the sustain and ERCnetworks of a PDP system are consideredhigh when designing with MOSFETs.

By contrast, IGBTs have traditionallycome into their own when a very high volt-

age rating of 600-1200V is required; well inexcess of the typical operating levels in aPDP application. Despite this, the superiorconduction characteristics of IGBT, arisingfrom its minority carrier action, are desirablefor PDP applications. In addition, the IGBTshares MOSFET benefits such as simplifieddrive requirements, as well as a wide safeoperating area (SOA) and high peak currentcapability. In addition, IGBTs can be con-nected in series without requiring dV/dtsnubbers.

During discharge mode, the IGBT is sub-jected to soft-switching, requiring, therefore,very low on-losses. In that case the productVCE ? IC is important, whereas in the caseof a MOSFET the product RDS(ON) ? ID2 isessential. As a result, the MOS technologyhas, with some enhancements, tended to

I G B T S

Trench IGBTS Ensures Low VCE(sat)

Low-loss sustain and energy recovery circuits for Plasma Display Panels

The latest generation of IGBTs are helping to improve the performance and efficiency offlat panel displays. The plasma display panel (PDP) is the technology of choice for largevideo display applications, from high-end TV and home cinema to exhibition and public

entertainment systems.

By Dr. Georges Tchouangue, Toshiba Electronics Europe (TEE)


Benefit from an integrated range ofproducts and solutions in the field ofpower electronics.

www.infineon.com

Come together

dominate the PDP application space, as faras sustain circuitry and ERC are concerned.

Best of Both WorldsStill, engineers searching to achieve a

convincing performance edge for new PDPproduct designs are keen to benefit fromthese advantages of IGBT technology, atlower voltages in the 250-400V range, andwithout exposure to the higher switchinglosses resulting from traditional IGBT con-struction. While MOSFET developmentfocuses on increasing the maximum ratedoperating voltage, to serve PDP and otherhigh voltage applications, new IGBT struc-tures are emerging that reduce saturationvoltage and conduction losses, and alsoenhance switching characteristics.

The IGBT, essentially, combines the drivecharacteristics of a small-signal MOSFETwith the conduction mechanism of a bipolarpower transistor. As such, IGBT develop-ment may focus on optimising one or theother side of its behaviour. Hence, whenchoosing an IGBT for a given application, itis important to consider the device proper-ties carefully to fit in with the operation of theoverall system. For example, an IGBT

designed to perform well when soft switch-ing is applied will perform differently in ahard switching application. The arrival in themarket of IGBTs optimised for PDP sustainand recovery applications further highlightsthis trend.

Application-Optimised TechnologyAn example is the latest, 5th generation

IGBT technology from Toshiba. Devices,such as the GT30G121 rated for 400V oper-ation and the GT30F121 for 300V operation,combine trench semiconductor processtechnology with low injection enhancementmode N-channel technology to meet theserequirements. The fabrication and construc-tion of these devices is specifically optimisedfor PDP applications. Trench technologyensures low saturation voltage (VCE(sat))resulting in a further reduction in typical con-duction losses, while enhancement modeensures fast switching characteristics. At thesame time the maximum pulse collector cur-rent (ICP) is 120A, which is sufficient foremerging PDP designs featuring staggered-sustain-pulse design to limit I2R losses gen-erally, while the gate-emitter voltage (VGE)is typically low for an IGBT, at 15V.

In the circuit of figure 1 these enhancedIGBTs are used to relieve transistor driverequirements and reduce conduction andswitching losses in the sustain and energyrecovery circuits, at typical PDP sustainrates.

Over and above the chip technology,component designers are also paying care-ful attention to important package details, tofurther drive down losses and to optimisethermal performance for high efficiency andto ensure a reasonable isolation voltage. Forinstance, low thermal impedance pathsbetween the chip and copper frame areessential to remove heat from the junction.The new Toshiba IGBTs feature electricallyand thermally optimised packaging technolo-gy, including the use of copper connectorsrather than traditional aluminium bondingwire. Both of the new IGBTs will operate witha junction temperature of up to 150ºC, andare packaged within the industry-standard,familiar and convenient TO-220 outline.

www.toshiba-components.com

I G B T S

Figure 1. PDP drive circuits, showing replacement of MOSFETs with application-optimised IGBTs in sustain and energy recovery circuits


Migrating appliances such as washingmachines from fixed-speed motor operationto more flexible variable-speed operation cansave energy while enabling design tech-niques such as advanced wash programsthat also reduce water usage.Washing machine designers have identifiedthe permanent magnet synchronous motor(PMSM) as the most cost-effective and easi-ly controlled choice for variable-speed motoroperation. Speed and torque control aremuch easier to establish than with traditionalinduction motors, and the PMSM typicallydelivers greater efficiency in terms of torqueper amp. This enables a smaller motor,thereby reducing per-unit costs and simplifying electrical and mechanical design. A barrier to the arrival of the next-generation,ultra-efficient washer, however, is the needto implement additional sensing componentssuch as Hall Effect sensors, to generate rotorpositional information. Alternatively, the soft-ware challenges associated with coding asensorless motor control algorithm introduce large risks to the projectand require specialist DSP or RISC program-ming skills.Designers can overcome this barrier with a

sensorless motor control algorithm inhardware tailored to meet specific systemrequirements. This approach allows designers to implement variable-speed motordrives quickly and cost effectively. Amongother important benefits, executing the algorithm at a higher speed indedicated hardware results in better speedand torque control compared to a software-

based approach. This provides greater flexi-bility for washer designers to create efficientprograms that use less electrical energy.

Sensorless Control Algorithm in Hardware In sensorless motor control, the algorithm

determines rotor position typically by estimat-ing the motor winding currents, becausedirectly sensing actual current in the wind-ings would require expensive signal isolationcircuits. A number of estimation techniquesmay be used, but the technique InternationalRectifier has adopted for the Motion ControlEngine (MCE) algorithm deployed in itsiMOTION platform for washers, derivesaccurate values from actual measurementsof current in the inverter DC link used todrive the PMSM, as shown in figure 1.

This produces an accurate representationof the motor winding because, in each PWMswitching cycle, there are two inverter-switching states when the current flowing inthe DC bus matches the current in a motorwinding. Hence, by sampling the DC link cur-rent twice in the PWM cycle, it is possible tomeasure two of the motor phase currents. A

Cost-Effective Variable-SpeedMotor Control

Washing machines are a target marketThe turbulent and steadily increasing price of energy, combined with increasing

government levies on resource usage, is sharpening homeowners’ focus on appliance energy efficiency.

By Aengus Murray, International Rectifier

Figure 1. Motor phase currents are calculated by sensing in the inverter DC link.

M O T I O N C O N T R O L


Figure 2. The designer selectsthe required functions from theMCE library.

calculation for the third phase current is gen-erated from the two measured currents sincethe three currents must sum to zero. Fromthis directly measured link current, therefore,IR’s MCE is able to extract accurate esti-mates for rotor angle and speed to drivespeed and torque control algorithms. The MCE actually provides a library of motorcontrol functional blocks as soft IP (figure 2)that the designer selects using a graphicalconfiguration tool. When the desired motor control functionshave been selected, a dedicated compilertranslates the control design into the MCEsequencer instructions that connect thehardware macro blocks in the correctsequence to implement the control system.This eliminates software coding from thedevelopment process, simplifying the imple-mentation of sensorless speed control. Thisnot only saves time and reduces depend-ence on specialised motor control designskills, but also reduces design errors.

A sample algorithm, implemented usingfunctional blocks from the IR MCE, is shownin figure 3. The MCE uses a two-phaseequivalent model of the PMSM circuit, to sim-plify rotor angle estimation. Hence, in thealgorithm shown, the three rotor current val-ues reconstructed from the DC link measure-ments are converted into equivalent two-phase values using the Clarke transformationfunction. Rotor flux functions are thenderived using the two-phase circuit equa-tions, from the current values produced bythe Clarke transformation and the voltagevalues produced by the forward vector rota-tion function (ej?). The rotor phase PLL thenensures accurate estimated values for rotorangle and speed.The Field Oriented Control (FOC) blocksshown in figure 3 decouple the transformedAC motor winding currents into two DC com-ponents representing torque (IQ) and flux(ID). This simplifies the controller design byallowing current loop tuning to become inde-pendent of speed. The speed loop then

becomes an outer loop, used to calculate thetorque reference command for the IQ loopbased on the speed error. The RAMP func-tion shown maintains motor accelerationwithin specified limits, and the LIMIT functionis implemented to prevent the motor currentexceeding the manufacturer’s recommendedmaximum.In the algorithm shown, an additional functionimplements reluctance torque control for aninterior permanent magnet motor (IPM).Reluctance torque is an extra component oftorque enabled by the unique construction ofan IPM, and is not present in surface perma-nent magnet (SPM) motors. IPM controlallows the designer to maximise the IPM’storque output by adjusting the phaseadvance. Since the MCE is configurable tomeet individual motor control requirements,the designer has the flexibility to exclude theIPM control block if not required.

Optimised Digital Control ICsBy implementing the MCE as configurable

hardware IP, International Rectifier openedthe door to an additional level of integrationin which one piece of silicon delivers theMCE and other motor control functions toreduce component count and developmenttime even further. Among the initial second-generation motion control ICs to feature theMCE on-chip, the IRMCF341 for washer

motor control applications, features an 8051-based microcontroller co-integrated on thesame silicon (figure 4) The MCU is capableof running the washer application softwareincluding sequencing, user interface, hostcommunication, and upper layer controltasks. The MCE and 8051-based MCU haveshared access to a dual-port RAM, allowingset points such as target speed, to be madeavailable to the MCU and the motion controlengine. This allows set points such as motorspeed to be adjusted under control of theapplication.

An analogue signal engine (ASE) also isintegrated on-chip, as shown in figure 4. The ASE implements special hardwaretailored to the single-shunt inverter

architecture to enable a direct connection ofthe shunt resistor to the IC without requiringdiscrete analogue and digital circuitry. A 12-bit ADC assists designers needing toadapt the gain of the amplifiers to meet specific system parameters, requiring onlyexternal resistor additions. Also, a numberof spare analogue input channels are available for application-specific requirements. For instance, connecting thegate driver temperature-sensing circuit to theASE and graphically inserting the appropriate blocks inside the MCE providesa route to implementing temperature protection. Another advantage is that, when fine-tuningthe digital control algorithm, the designer canrewrite control parameters and system vari-ables quickly via the 8051 MCU communica-tion ports, using the IR MCEDesigner PC-based configuration tool. This allows rapidfine-tuning of the motor control algorithm, tofurther streamline development of variablespeed washer motor controls.

www.irf.com/eu



Figure 3. Configured motion control algorithm including field weakening.

Figure 4. MCE and co-integrated 8051 microcontroller, with A/D also on-chip.

When selecting such a device,designers are faced with awide variety of choices, from

microprocessors to digital signal processors(DSPs) to modules. Small form factor micro-controllers (MCUs) can bring an array ofbenefits to applications, such as motor con-trol for small motors, while saving valuableboard space. Let’s first take a deeper lookinto motor control and its specific require-ments.

Motor Control BasicsSmall motors (less than 300 W) are

found in a wide variety of applicationsincluding automobiles, printers, copiers,paper handlers, factory automation, spaceand military vehicles, test equipment androbotics. The quantity of motors produced isapproximately inversely proportional to thepower level; therefore, small motors are pro-duced in much greater quantities than largermotors. The most popular small motorstypes are dc, brushless dc and steppermotors.

The primary distinguishing featurebetween stepper, dc and brushless dcmotors is the manner in which they are driv-en. Stepper motors are moved in discretesteps. DC and brushless dc motors are typi-cally controlled using continuous mode ana-log control methodologies. Because steppermotors are driven in discrete steps, theyexcel at absolute positioning applications.The most commonly available steppermotors move in precise increments of 1.8°or 0.9° per step. Stepper motors are con-trolled directly and the primary commandand control variable is the step position. Thisis in contrast to dc motors where the controlvariable is the motor voltage, and the com-mand variable may be either position orvelocity. A dc motor requires a feedbackcontrol system and controls the position indi-rectly. A stepper motor system is normallyoperated “open loop.”

Stepper MotorsStepper motors may be classified by their

motor construction, drive topology and step-ping pattern. There are several differenttypes of stepper motor construction. Theseinclude variable reluctance, permanent mag-net and hybrid permanent magnet.Permanent magnet stepper motors are veryinexpensive and are often used in inexpen-sive consumer products. Hybrid steppermotors are a bit more expensive and arepredominant in industrial motion controlapplications. Variable reluctance motors typi-cally have three or five phases and require adifferent drive topology.

The two common drive topologies forstepper motorsare unipolar andbipolar. A unipo-lar drive usesfour transistors todrive the twophases of thestepper motor.The motor hastwo center-tapped windingswith six wiresextending fromthe motor asshown in Figure1. This type ofmotor is some-times, rather con-fusingly, called afour-phase motor.This is not anaccurate repre-sentation as themotor really only has two phases. A moreaccurate description would be a two-phase,six-wire stepper motor. A six-wire steppermotor is also often called a unipolar steppermotor. However, a six-wire stepper motorcould be used with either a unipolar or bipo-lar drive.

A bipolar stepper motor drive uses eighttransistors to drive the two phases as shownin Figure 2. A stepper motor with four or sixwires may be used with a bipolar drive. Afour-wire motor can only be used with abipolar drive. The four-wire motor might bemarginally less expensive in high volumeapplications. The bipolar stepper motor driveuses twice as many transistors as the unipo-lar stepper motor drive. The four lower tran-sistors can usually be driven directly fromthe MCU. The upper transistors require amore expensive high-side drive. The bipolardrive transistors only need to withstand themotor supply voltage. The bipolar drive doesnot require a clamp circuit like the unipolardrive.

DC and Brushless DC (BLDC) MotorsDC motors are the most common and

least expensive of all small motors and areused in a wide range of applications. BLDCmotors promise improved reliability, reducednoise and, potentially, lower cost. However,BLDC motors have only supplanted conven-


Smaller is Better for MotorControl Designs

In today's space-constrained environments, designers are looking fora solution for their application that is feature-rich in a small package

without compromising performance.

By Agustin Schuster, Silicon Laboratories Inc.

Figure 1: A Unipolar Stepper Motor Drive


tional dc motors in a few specialized high-volume applications, such as disk drives andcomputer fans. In certain applications, BLDCmotors offer some advantages over conven-tional brush-commutated dc motors. Theelectronics and sensors effectively replacethe role of the brushes, offering long life,reduced maintenance and no brush noise.The characteristics of a dc motor make it theeasiest motor to use in a variable-speedsystem. The hardware configuration of a dcmotor is illustrated in Figure 3.

Selecting the Right Device for Controllingthe Motor

When selecting a device for a specificapplication, such as motor control, it isimportant to look at the features offered andrealize the benefits of each to the applica-tion. Stepper, dc and brushless motors areoften controlled using special function inte-grated circuits (ICs) that provide limited con-trol functionality. Such ICs often employ arudimentary step forward and back interfaceto the microprocessor that limits system per-formance.

In embedded systems it is much better touse a small form factor MCU, such as theC8051F3xx family, to directly control themotor. The C8051F3xx family is capable ofproviding a high performance motion controlsolution. The MCU implements a linear-velocity profile, generates the precise timingrequired and outputs the pattern used todrive the motor. The MCU directly drives thepower MOSFETs, and no additional gatedrive circuitry is required. The MCU alsoprovides serial communications for remotecontrol and distributedsystems.

An entire steppermotor drive can easily beintegrated onto the backof a small stepper motor.A system with multiplemotors may use a singlesmall MCU for eachmotor. The C8051F3xxfamily is ideally suited fordriving a stepper, brush-less or dc motor. Thesmall form factor lendsitself to integrated motorsolutions. The on chipUART and SMBus pro-vide serial communica-tion and control. The cali-brated internal oscillatoreliminates the cost andpin-count of using anexternal crystal, while

providing an accurate time base for highspeed UART and precise motor timing. Thelow pin count package has enough pins todrive the motor and RS232 transceiver, withtwo additional I/O pins left over for specialfunctions.

Silicon Laboratories’ highly-integratedfamily of small form factor MCUs, theC8051F3x family, offers a number of fea-tures that are optimized for space-con-strained, low-power, low-cost applications inconsumer, industrial, communications andautomotive markets.

Available in one of the world’s smallestMCU footprints (3 x 3 mm), the C805F3xfamily of devices features a pipelined 25MIPS 8051 CPU providing a 20x to 25x per-formance improvement over the original8051. Other on-chip features include: soft-ware-writable 2-16kB Flash memory, a twopercent accuracy precision internal oscilla-tor, up to 1280 Byte RAM, up to a 10-bitADC, temperature sensor, four 16-bit timersand 5-channel PCA and flexible I/O. By inte-grating these common external components,the C8051F3xx family eliminates expensiveand bulky discrete components. All of these

features are integrated into remarkablysmall micro lead-frame packages (MLP)allowing system designers to reducecomponent count and overall size whileimproving system performance (Figure3).

Silicon Laboratories' MCUs trulydeliver a compact, mixed-signal, system-on-a-chip. Development is quick andeasy due to low-cost, professionaldevelopment tools and in-system debug.High integration, small size, high CPUthroughput and best-in-class analogperipherals make the C8051F3xx familyideal for a wide range of applications,such as motor control.

www.silabs.com


Figure 3: Feature Set of Silicon Laboratories’ C8051F3x MCU Family

Figure 2: A Bipolar Stepper Motor Drive


Designers continue to encountermany challenges optimizing syn-chronous buck regulators.

Different MOSFET and driver combinationsyield a wide range of design challenges.Ringing on the switch node can be a sourceof conducted and radiated EMI. Differentpackages and switching characteristics ofMOSFETs can adversely affect the behaviorof MOSFET drivers. Not all layouts areideal; therefore, designer must adjust the cir-cuits around the MOSFET, driver, and scruti-nize component selection.

Case 1: Oscillation or ringing on thephase node has two adverse effects. Peakvoltages during oscillation can exceed 80%of maximum VDSS on a MOSFETdatasheet, which is a typical guideline set byreliability engineers. Ringing is a source ofradiated and/or conducted signal that resultsin noise on sensitive digital traces orcausing EMI system testing failure.

These are possible solutions:# slow down both rising and falling edge

time of high side FET (add R1)# slow down only the rising edge time of

the high side FET (add Rboot)# decreasing the drive voltage applied

to the gate of the high side FET (addC1 or decrease VCC)

# decreasing the drive voltage appliedto the gate of the low side FET(decrease VCC)

# decreasing layout loop area for lowside FET to lower loop inductance.(LDRV to PGND loop)

# decreasing parasitic inductance byselecting advance packages inMOSFETs, Lp = Lss + Ldd.

# Select MOSFET with low Qrr, which isa portion of Coss and contributor toCp.

Note: To decrease the drive voltage tothe HDRV pin, C1 ~ Cboot / 5 is a goodstarting point. Decreasing VCC and thus thedrive voltage can also be achieved by plac-ing two boot diodes in series. To lowerinductance of the LDRV to PGND loop,place driver close to the low side transistor.To minimize layout related inductance fromlow side FET source lead (Ldd) to PGND,place a near solid connection betweenPGND copper layer and source leads.

Any combination of the above can beused depending on MOSFET selection(package and silicon characteristic depend-ent) and type of circuit layout. Figure ofimplementation are shown below.

Lss = package inductance on the sourcelead

Ldd = package inductance on the drain leadLp = parasitic inductanceCp = parasitic capacitancefo = = resonant frequency of sinusoidal SW

nodefsw = switching frequency of converterRs = snubber resistorCs snubber capacitor

The application example demonstratesdecreasing the HDRV voltage too low.Switch node signal above the voltage onHDRV pin causes the high-side transistor'sgate-source voltage to fall below the Vgs(th)once or even multiple times during the peri-od. This results in higher switching losses,which decreases efficiency.

Inspection of Figure 2 and 3 shows thatQ1 travels through the active region (t2 - t3)and the ohmic region (t4 - t5) more than one

time. This indicates additionalswitching losses incurred for thehigh side transistor. IncreasingHDRV voltage by decreasing oromitting C1 will lower the addi-tional switching losses.

When above options areexhausted, using a RC snubbercircuit is a popular choice.Tuning the RC snubber, which isRs and Cs in Figure 1, can bedone using the following proce-dure:

1)Apply load on the regulatorwithout the RC snubber populat-ed. Probe the switch node orlow side MOSFET until reso-nance is observed. Find the res-onant frequency on the risingedge of the switch node (fo1).When measuring switch node,use as short ground lead on the

P O W E R M A N A G E M E N T

Optimizing Synchronous Buck Regulators The challenges in DC/DC designs

Adaptive gate drive circuits in MOSFET drivers ensure minimum dead time while pre-venting potential cross conduction currents. Both high and low-side transistors turn on

creating a low impedance path from input voltage to ground.

By Richard Chung, Member of Technical Staff, FAE, Fairchild Semiconductor

Figure 1, Synchronous buck Equivalent Circuit


http://www.ro.feri.uni-mb.si/epe-pemc2006

August 30 - September 1, 2006Portorož, Slovenia

Technical Co-Sponsors:Organizers: In co-operation with:

th12 International Power Electronics

and Motion Control Conference

th12 International Power Electronics

and Motion Control Conference

EPE - PEMC 2006

Topics1. Semiconductor Devices and Packaging2. Power Converters3. Control of Power Converters4. Electrical Machines and Actuators5. Motion Control, Robotics, Adjustable Speed Drives6. Application and Design of Power Electronic Systems7. Measurements, Sensors and Observing Techniques8. Electromagnetic Compatibility9. Power Electronics in Transportation10. Mechatronic Systems11. Power Electronics in Electrical Energy Generation,

Transmission and Distribution12. Renewable Energy Sources13. Active Filtering and Unity Power Factor

Correction Circuits14. Education15. Industry Related Topics

ContactEPE-PEMC 2006 Conference SecretariatFaculty of Electrical Engineering and Computer Science, University of Maribor Smetanova ulica 17 SI-2000 Maribor, SLOVENIAE-mail: [email protected]

EPE-PEMC Council or EPE Member:500 EUR

Non EPE-PEMC Council or EPE Member:550 EUR

Student fee (not for authors): 150 EUR

Advanced Registration Fees -June 10, 2006

Advanced Registration Fees -June 10, 2006

®

S L O V E N I A S E C T I O N

probe tip to minimize error due to loopinductance.

ωo1 = 2πfo1 = [1]

Add a capacitance (Cadd) across the drainto source of the low side FET, and onceagain find the resonant frequency (fo2).

ωo2 = 2πf o2 = [2]

Once fo1 and fo2 is observed, a relationshipcan be derived between Cadd and Cp. Onecan verify thatfo1 / 2 = fo2 ; Cadd = 3 x Cp [3]

fo1 x 0.75 = fo2 ; Cadd = (9/7) x Cp [4]Note: A MOSFET datasheet will typically

not have lead inductance value. A PSPICEmodel does not account for layout traceinductance. It is recommended to calculateLp (using equation [1]) after Cp is found.

3) In order for the RC snubber circuit to cre-ate a critically damped response, Rs shouldbe selected according to. Recall from aseries RLC natural response that

Q = [5]

Q = 1; critically damped responseQ > 1; under-damped response - want snub-

ber to respond fast to Lp, Cp oscilla-tion

Q < 1; over-damped response - want snub-ber to respond slower to Lp, Cp oscillation

Select the available resistor value near cal-culated Rs as a starting point where Q = 1.Adjust Rs to achieve desirable voltage levelof damping on SW node.

4) Many snubber papers advise the useof Cs = 2 * Cp, but this creates additionalpower dissipation on Rs that may not beacceptable. From the average power dissi-

pation formula (Step5), it is clear that Csselection is a factorin power dissipation.A compromise mustbe made where Cp <Cs < 2 * Cp, whenefficiency is impor-tant in the design.When selecting theproper power ratingfor Rs, consider thepeak energy storedin Cs during chargingand dischargingcycles.

w = (Cs x Vin2) / 2wtotal = (Cs x Vin2)

Since energy is time dependent, averagepower dissipation is:

Pd ~ Cs Vin2 fsw [6]

When Steps 1 through 5 does not dampenyour oscillation, it is necessary to examinestability of the input filter. In abstract pub-lished by R.D. Middlebrook, stability or non-oscillatory condition is achieved if:

[7]

D = Vout/Vin ; duty cycleEquation [7] lowers the Q that is around theresonant frequency of input L and C.

Looking at table below provides good insighton inductances due to wire bond and leadframe found in different packages forMOSFETs and additional parasitic elementsthat are present due to layout and printedcircuit board (pcb).

Case 2: There is a gate bump voltageabove the low side transistor's threshold Vgs

that causes thelow side andhigh side fets tobe on simulta-neously. Thiscan create arepetitive shortcircuit conditionevery switchingcycle. Althoughcross conduc-tion time is only5-10ns percycle, it canresult in thermalrunaway situa-tion over time

where the FET

exceeds the maximum junction temperature.High dv/dt on the phase node, Cgd and Cgscapacitor ratio, Qrr, and pull down imped-ance of the driver are all contributors to thegate bump seen.

Adaptive gate drive circuits in MOSFETdrivers ensure minimum dead time whilepreventing potential cross conduction cur-rents. Both high and low-side transistorsturn on creating a low impedance path frominput voltage to ground. This usually causesmore stress to the smaller die high side tran-sistor, since it is selected to minimize thedominant switching loss component. Itrequires less time to reach the power dissi-pation limits of the smaller die high side tran-sistor versus the larger die low side transis-tor. Although adaptive gate drive circuits areintelligent, it can only take voltage informa-tion from the HDRV, LDRV, and SW pinsand makes a decision for switching transi-tion. Because it cannot read the internalVGS, it does not know if the transistor isfully on or off. The following factors furtherlimits adaptive gate-drive circuit's ability toprevent potential cross conduction.

When a low side transistor is exposed toa dv/dt event, there are two current paths.In Figure 4, path (a) current creates addi-tional Vgs seen at the internal gate of thetransistor.Igs = Cgd × dv/dt [8]Igs = Vgs / Zgs [9]T = Zgs (Cgd + Cgs)Zgs = driver pull down resistance + externalresistor between HDRV and gate of MOS-FET + internal MOSFET gate resistancev(t) = Vin - Vin × e ^ ( -t / T )dv/dt = (Vin / T ) × e ^ ( -t / T )combining equations [8] and [9] to solve forVgs,

RinCinLin×

2DRout⟨

RsCpLp /

)(1

CaddCpLp +×

CpLp×1


Figure 2. Rising transition when Q1 turns on and Q2 turns off. Red waveform is Vgs of high side fet.

Figure 3. Turn on waveforms where t1 to t3 makes up switching losses(AN-9010 page 16)


Vgs = Zgs × Cgd × (Vin / T ) × e ^ ( -t / T ) =Vin × [ Cgd / ( Cgd + Cgs ) ] × e ^ ( -t / T )As t → 0,Vgs = Vin * [ Cgd / ( Cgd + Cgs ) ] [10]

When rise time, t, of dv/dt equationapproaches zero, approximate addition ofVgs to the gate is shown by equation [10].This means larger Cgd can amplify addition-al gate bump seen on low side during adv/dt event.

Additionally, path (b) current can causeavalanche breakdown due to parasitic bipo-lar transistor turn on. When parasitic bipolartransistor turns on due to dv/dt, the break-down of the bipolar device is reduced to 50 -60% of BVCBO. More detail of avalanchediscussion can be found in AN-9010, "MosfetBasics" - from Fairchild Semiconductor.Capability of dv/dt on the parasitic bipolardevice is:dv/dt = Vbe / (Rb * Cdb)During a switching cycle when both high andlow side transistors are turned off, the lowside body diode is conducting and minoritycharge accumulate in the body diode.Referring to Figure 1, this current path is inthe direction of L1, Cout, and body diode ofQ2. When Q1 turns on, diode reverse

recovery current (Irr) removes the minoritycharges in the body diode. The recoverycharacteristic of the body diode is seen onthe dv/dt across the low side transistor, Q2.

Today's drivers have low pull downimpedances (<1 ohm) to handle increasingdemand of larger die and lower Rds(on)transistors. Low pull down impedances ofLDRV highlight transistors that have highinternal gate resistance, Rg. When LDRV ispulled low, the driver will make a decisiondependent on what voltage it sees on theLDRV. Looking at Figure 5 and 6, it is clearthat Figure 6 demonstrates a case where thehigh side transistor will be turned on beforethe low side transistor is off. In Figure 6, it isnot possible for the transistor to dischargewithin 5ns doing simple RC time calcula-tions. Adaptive gate drive circuits may varybetween IC vendors; therefore, schemes inhandling the transitions will vary.

Selecting the proper transistor not onlymean looking at Qg and Rds(on). It requiresscrutiny to other parameters such as Cgs,Cgd, Qrr, and Rg. Damage to the transistoror possible catastrophic failure can occurdue to transistor interaction with a MOSFETdriver. Power dissipation associated with

cross conduction or dv/dt is possible in theconditions described.

Oscillation on the switch node can becontrolled with proper design of the input fil-ter and RsCs values. Cross conduction isminimized with attention to layout, MOSFET,and driver selection. Design suggestionsdiscussed can offer improvements when theideal layout cannot be accomplished.

References1) Fairchild Semiconductor AN-9010 "MOS-FET Basics"2) R.D Middlebrook, "Input FilterConsiderations in Design and Application ofSwitching Regulators" from Advances inSwitched-Mode Power Conversion book

www.Fairchildsemi.com


Table 1. Inductance of different package types

Figure 4. Equivalent circuit of N-channelMOSFET (Reference AN-9010, page 27)

Package Ldd (nH) Lss (nH) Lgg (nH)

SO8 0.457 0.901 1.849

SO8 wireless 0.601 0.709 0.932

IPAK (TO-251) 2.92 3.49 4.63

DPAK (TO-252) 0.026 3.73 4.87

FLMP SO8 0.032 0.477 0.865

Figure 5. Low side Gate pin (LDRV) on driver waveform looks like normal discharge of Ciss on FET

Figure 6. LDRV circuit fooled due to high resistance betweenHDRV and VGS internal to FET


Digital power conversion, usingDSP within the regulation loop,may or may not be advanta-

geous. For traditional DC/DC converters(analog power conversion), these systemsstill may require margining and telemetry -digital monitoring of load current and volt-age. Digital management of high availabilitypower supplies holds great promise, but it

often comes at the cost of complicated multi-chip circuit solutions. For example, an appli-cation with voltage-current monitoring andsupply voltage margining can require a num-ber of ICs, including a low-drift reference, amultiplexed, differential input ADC with atleast 12 bits of resolution, an 8-bit DAC, anda dedicated microcontroller. Add to this theconsiderable software development effort

required for margining algorithms, voltageand current monitor functions, and the cost,complexity, spacious board real-estaterequirements and blossoming design-debugtime can deter even the most dedicatedpower supply designer from trying digitallymanaged power.

Application-specific devices such as theLTC2970 offer an alternative to the multi-chip approach and simplify the design ofdigitally managed power supplies. Figure 1shows a block diagram of the LTC2970,highlighting the main functions.

Margining and Monitoring ApplicationFigure 2 shows a typical application cir-

cuit for monitoring and margining a DC/DCconverter with external feedback resistors.

An ADC's differential inputs sense thevoltage directly at the point-of-load whileanother pair of differential inputs monitor thevoltage across sense resistor R50. TheDC/DC converter's output voltage can bemargined to precise, user-programmableset points by a linear search algorithm thatcompares the digitized point-of-load voltageagainst the target. The current beingsourced by an IDAC is then adjusted asneeded one LSB per servo iteration. Thiscurrent develops a point-of-load ground ref-erenced correction voltage across resistorR40 that is buffered to the VOUT0 pin. Theresulting voltage differential between theVOUT0 pin and the converter's feedback

D I G I T A L P O W E R

Take the Easy Road toSimplified Techniques forDigitally Managed Power

Built-in servo algorithm reduce the burden on system computing resources

Ensuring high reliability in servers, telecom and network switching equipment or otherhigh availability systems can involve centralized monitoring and control o f power sup-plies. It becomes incumbent upon the power supply designer to learn the techniques of

digital power management.

By Todd Nelson, Product Marketing Manager, Linear Technology

Figure 1: Block diagram LTC 2970


node is multiplied by a factor of -R20/R30and added to the nominal output voltage ofthe DC/DC converter, thus closing the servoloop. When voltage margining is disabled,the converter's feedback node can be isolat-ed by placing the VOUT0 pin in a highimpedance state.

Figure 3 shows a similar application witha DC/DC converter with a TRIM pin. As inFigure 2, two external resistors are required:VOUT0 connects to the TRIM pin throughresistor R30 and IOUT0 is terminated at theDC/DC converter's point-of-load ground byR40. Following power-up, the VOUT0 pindefaults to a high impedance state allowingthe DC/DC converter to power-up to its nom-inal output voltage.

Applications that need to be sequencedcan be configured to hold off the DC/DCconverter upon power-up. This causes theGPIO pin to automatically pull the DC/DCconverter's RUN pin low until the SMBuscompatible I2C interface releases it.

The absolute accuracy of the LTC2970 isdemonstrated in Figure 4. The LTC2970 isconfigured to servo one of the outputs of aLTC3728 DC/DC converter to 1V if the con-verter's voltage deviates by more than±0.1%. The LTC2970 is easily able to holdthe output voltage to within ±1mV of 1Vwhile both it and the DC/DC converter areheated from -50°C to 100°C. When theLTC2970 is isolated from the LTC3728, theoutput voltage drifts between 1.002V and1.0055V over the same temperature range.

Main Functions, Delta-Sigma ADCThe ADC used in the LTC2970 is a sec-

ond-order delta-sigma modulator followed bya sinc2 digital filter that converts the modula-tor's serial data into a 14-bit word at a con-version rate of 30Hz. The ADC's TUE is lessthan ±0.5% when using the on-chip refer-ence.

One advantagedelta-sigma ADCsoffer over conven-tional ADCs is on-chip digital filter-ing. Combinedwith a large over-sampling ratio(OSR = 512), thisfeature makesthem insensitive tothe effects ofnoise when sam-pling power-supplyvoltages. Thesinc2 digital filterprovides highrejection except atinteger multiplesof the modulatorsampling frequency, fs = 30.72kHz. Adding asimple RC low-pass filter at the input of theADC attenuates ripple components that havethe potential to alias to DC.

The ADC's differential inputs can monitorsupply voltages at the point of load andsense resistor voltages. This is preferable toground-referenced inputs found in mostmicrocontrollers. The differential and com-mon mode input ranges span -0.3V to 6V.With its 500µV/LSB resolution, the ADC canresolve voltages for a wide range of loadcurrent across sense resistor values of onlya few milliohms.

Voltage Buffered IDACsFigure 5 illustrates how each of the

LTC2970's continuous-time IDACs connectsto a DC/DC converter with an external feed-back network. This provide a smoother tran-sition than PWM DACs. The servo'd correc-tion voltage is set by resistor R40. SinceR40 is terminated at the point-of-loadground, the correction voltage is insensitiveto load induced ground bounce. The correc-tion voltage is buffered to the VOUT0 pin by

a unity-gain ampli-fier whose outputcan be placed in alow-leakage(<100nA), highimpedance state.Resistor R30 con-nects the VOUT0pin to the feed-back node of theDC/DC converter.The range andresolution overwhich the correc-tion voltage canmove the convert-

er's output is adjustable via resistor R30.

A "soft-connect" feature allows theLTC2970 to automatically find the VOUT0voltage that most closely approximates theDC/DC converter's feedback node voltagebefore enabling the voltage buffer thus mini-mizing any disturbance to the converter'soutput voltage.

There is no body diode from the VOUT0pin to the LTC2970's VDD supply, and theVOUT0 pin goes into a high impedancestate when VDD drops below the LTC2970'sundervoltage lockout threshold. So no spe-cial precautions need to be taken in theevent the DC/DC converter is still activewhen the LTC2970 powers down as wouldbe required in the multichip approach.

Voltage ServoThe voltage servo feature can be config-

ured to trigger on under voltage and/or overvoltage events, run continuously, or run justonce. The LTC2970 relies on a simple linearsearch algorithm to find the IDAC code thatresults in an ADC input voltage that mostclosely corresponds to the servo target. Thepolarity of the servo algorithm can be pro-grammed as inverting (default) or non-invert-ing.

Voltage MonitorThe LTC2970 is able to perform ADC

conversions on any combination of sevendifferent input channels. Over-voltage andundervoltage threshold registers allow theuser to define instantaneous and/or latchedfaults in the event one of the input voltagesdeviates outside an acceptable window. TheGPIO_0 and FAULT pins can be configuredto assert if a fault occurs.

D I G I T A L P O W E R

Figure 2: Typical application circuit for monitoring and margining aDC/DC converter with external feedback resistors.

Figure 3: Application with a DC/DC converter with a TRIM pin.


ConclusionThe LTC2970 was used to explore the necessary functions

essential for digitally managed, high availability power applications.A multiplexed, differential input 14-bit delta-sigma and a low drifton-chip reference are necessary if the application is expected todeliver less than ±0.5% total unadjusted error. Two continuous-time, 8-bit, voltage-buffered IDACs can also be programmedthrough the I2C and SMBus compatible interface to servo power-supplies to the desired voltages. Extensive, user configurable faultmonitoring and a built-in servo algorithm reduce the burden on sys-tem computing resources and shorten software development time.The result is an accurate method to provide digital power manage-ment and ultimately higher reliability to high availability systems.

www.linear.com

Figure 4: Corrected and uncorrected DC/DC converter output voltage vs temperature

Figure 5: LTC2970's continuous-time IDACs connects to a DC/DCconverter with an external feedback network.

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Have you ever taken a moment toconsider how far the automobilehas come? In the 1800s, a lot of

experimenting was going on to developtransportation that didn’t require horses,cows or donkeys. Early versions of theautomobile (horseless carriage) were steam-powered, loud and dirty, and some wereeven electric with crude batteries and shortranges. With the invention of the internalcombustion engine, automotive transporta-tion began to take off. Still loud and dirty, ithelped to be rough and ready to be theproud owner of one of these hand-crankedwonders. Even so, demand was high.Somehow, people just craved owning theseill-mannered beasts, seeing they wouldmake life easier, better.

Over the last century, the automobile hasdeveloped into more than just transportation.No longer loud and dirty, we ride in comfortand luxury with all manner of safety, commu-nications and entertainment systems toaccompany our speedy journeys.Developments continue with new hybriddesigns that utilize both the internal combus-tion engine and the electric motor – improv-ing both fuel economy and performance.Current design efforts for the next decade

leave the internal combustion engine andconventional fuels behind, trading a nearlyexhausted resource for abundant hydrogen.It won’t be long and cars will be running onwater, kind of.

Our desires for speed, comfort, conven-ience and safety have been the drivingforces behind automotive innovation overthe decades – but not just automotive inno-vation. Those desires have also driveninnovation in other areas of transportationand life, such as housing and communica-tions. Our modern homes are filled with allof these things while the dreamers of tomor-row promise us even more.

Over the last half of the 20th century, weenjoyed the increasing comfort and conven-ience of radio, TV, home entertainment sys-tems, the rise of the Internet and personalcellular communications. By the turn of this21st century, we were enjoying music onCDs, movies on DVDs, digital radio/TV withsurround sound, immediate informationaccess and the convenience and safety ofpersonal cellular communications.

We are now about to enter a whole newera of electronic fantasy turned reality – an

era of commu-nicationssophistication,yet simplicity,that parallelsthe arrival ofour luxurysedans. Allforms of elec-tronic mediaare now con-verging in atotally digitalworld. Nolonger will our

communications, information and entertain-ment systems exist as separate entities. Weare at the cusp of a great merge, a wholenew level of comfort, convenience, safetyand speed.

The home of the near future is one inwhich control, communications, informationaccess and all forms of media content areavailable in any and all locations throughoutthe residence. Some call this the greatTriple Play - voice, video and data every-where in our homes. The whole-housebroadband network is arriving with plug-and-play convenience to comfort us with all ofour media, information and communicationswants and needs.

Imagine having instant access to yourbroadband Internet connection, outsidestreaming media (music, high-definition andstandard definition video), surveillance secu-rity system, voice communications Voiceover Internet Protocol (VoIP) and an in-house media server, or Personal VideoRecorder (PVR), with all of your favoritemusic and videos from any location in yourhome.

How will this be possible? Will we havea totally wireless in-house network? Notexactly – wireless access points cover zonesin a home or building, leaving gaps andweak, low-data-rate areas in between.However, some see whole-house networkingusing wireless nodes (access points) inter-connected by Cat-5 Ethernet cabling, whichhas to be installed and left behind when youmove, a real problem especially for renters.

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By Mark E. Hazen, Senior Technical Writer, Intellon Corporation

Figure 1: Interactive TV Screen


direct access via the AC outlets everywherein the home. No new wires are needed. Infact, existing TV cabling in the home mayalso be used if desired and a wirelessaccess point can be added anywhere toaccommodate notebook, tablet or PDAmobility.

AC powerline and coax cable both net-working together is what Intellon Corporationcalls a hybrid network, sort of a parallel tothe hybrid cars of today – both have twomeans of conveyance adding to the overallpower.

What’s more, all of our network-enabledequipment (PCs, TVs, radios, PVR/mediaserver, VoIP telephones, video surveillanceand more) will either have an embeddedadapter or simply use a plug-in-the-wallmodule to access the powerline Ethernetnetwork throughout the residence. Nothingcould be simpler.

Powerline Ethernet networking technolo-gy has been maturing for over a decade.Rallying the troops and leading the way inthis arena of innovation is the HomePlugPowerline Alliance, an international commu-nity of visionaries from hardware/softwaredesigners to network operators and serviceproviders. Member companies on theHomePlug Alliance’s Board of Directorsinclude Intel, Sony, Comcast, RadioShack,Cisco-Linksys and Sharp, among others.The Alliance develops performance andcompatibility standards and its mission is toenable and promote rapid availability, adop-tion and implementation of cost effective,interoperable and standards-based homepowerline networks and products.

The HomePlug Powerline Alliance’sHomePlug 1.0 standard was released in

2001, offering data rates as high as 14Mbps, similar to the performance of IEEE802.11b-based wireless. IntellonCorporation’s enhanced HomePlug 1.0 withTurbo has elevated data rates to as high as85 Mbps, out-performing IEEE 802.11a/gwireless networking devices. Intellon’s‘Turbo’ ICs are being used now in the firstwave of products for whole-house broad-band network deployment.

In August 2005, the Alliance announcedand released the HomePlug AV(Audio/Video) powerline-networking stan-dard, which drives channel bit rates to ashigh as 200 Mbps. The content throughputrates over the entire in-house powerline net-work are actually higher than any cable,satellite or telco-based xDSL pipelines thatbring the content and Internet to the home(optical fiber to the home excepted).

What this means is, the HomePlug AVstandard, and resulting HomePlug AV certi-fied equipment, is the enabling technology to

make the whole-housebroadband network fantasy areality, including the in-housedistribution of high-definitionTV/video. Service providersof all kinds are extremelyinterested because the serv-ices they provide can now bemade available everywherein the home with no addition-al truck rolling or expert man-power to deliver it and set itup. It’s all plug and play.That takes additional costsout of the picture, making itmore affordable for all.Intellon Corporation is nowshipping HomePlug AV stan-dard-compliant ICs in quanti-

ty to meet this rapidly emerging market.Other HomePlug IC manufacturers are soonto follow.

Telco and cable TV companies have longcompeted for subscribers to their Internetaccess services. This competition isexpanding as telephone companies areadding Video on Demand (VoD) InternetProtocol TV (IPTV). Combined with whole-house powerline networks, you will be ableto watch any TV program from anywhere inyour home. Instead of all of the channelscoming into your home at once, as is donewith cable TV, you will simply select yourdesired channel and it will come to yourhome from an outside program server overthe phone network using your High- or Very-high-data-rate Digital Subscriber Line(HDSL/VDSL) modem. The goal is for thisIPTV VDSL to support the streaming of acouple HDTV and a few SDTV channels atthe same time. The HomePlug AV whole-house network will then easily carry thesestreams throughout the residence. How’sthat for a luxury sedan?

Yes, we’ve come a long way from theearly days of driving the ill-mannered beaststo the smooth, fast, comfortable and safeluxury machines of today, some sportingnew hybrid power and efficiency. And, asyou may have guessed, I’m not just talkingabout automobiles. So, keep your seatbeltsfastened and enjoy the ride with high-speedubiquitous access to all content from any-where in your home. Cigar anyone?

www.homeplug.org

www.intellon.com

C O M M U N I C A T I O N P O W E R

Figure 2: Just-Plug-It-In

Figure 3: Hybrid House


For current transformers used inthese meters as sensing elements,the requirement of the core materi-

al is high permeability and low loss at powerfrequency (50 Hz). Ferrite materials havenegligible loss at 50 Hz; if a ferrite core isused in current transformer for this applica-tion the material must have permeability inthe range of 7000 and a relatively flat per-meability vs temperature (m-T) curve from0oC to 70oC without any pronouncedSecondary Permeability Maximum (SPM)peak. The material T36 has been developedwith this in view and also aimed at competi-tive pricing for the Energy meter market.

Application of Soft Ferrite Ring Cores inElectronic Energy-Meters

There has been wide use of soft ferritering cores in Electronic Energy meters inIndia. The ring cores are wound as BarPrimary current transformers and the loadcurrent (at 50 Hz) of the Energy meter ispassed through the single turn primary. Thesecondary typically has few thousand turnsof thin copper wire with dc resistance in therange of few hundred ohms and is terminat-ed by a metal film burden resistor below 50ohms. The voltage across the resistor is pro-portional to the load current of the Energymeter and is taken as a galvanically isolatedcurrent signal by the meter.

For uncoated ring cores an insulatingtape is put on the surface and two leads arebrought out from the winding. The woundtransformer is put in a plastic casing andpotted with resin. For coated ring cores thewinding is done directly on the core withoutputting any insulation tape.

For Accuracy requirement the Energymeter under test (with the wound ring core)is checked against a Standard Meter and theerror is noted. The error can be due to theratio error or the phase error of the ferritewound current transformer. The ratio errordepends mainly on the power loss in thecore and for ferrites at 50 Hz this is negligi-ble. The phase error depends on the induc-tance (AL) of the ring core and higher the ALlower is the phase error. Based on this thewinders have specified minimum acceptancelevel for AL value of these ring cores whichtranslates to a minimum value of the materi-al permeability.

Additionally, as the wound current trans-former is put in a plastic casing and pottedwith resin with thermal stresses involved dur-ing curing, the core material permeabilitymust be as far as possible invariant withtemperature so as not to allow shift in induc-tance after potting. The permeability vs tem-perature curve should be relatively flat from

10oC to 70oC with no pronouncedSecondary Permeability Maximum (SPM)peak in this temperature range.

Development of T36T36 material has been developed with

the view to keep the permeability close to7000 with no pronounced SPM in permeabil-ity temperature curve from 10οC to 70οC.The magnetic and electrical parameters aregiven below in Table 1 for this new material.

A typical calculation is shown below forring core R22 (OD=22.1 mm, ID=13.7 mm,Height=10 mm). This dimension suits themanufacturers casing and also availableEPCOS tooling. The metal film burden resis-tor is considered as Unity Power Factor atthe operating frequency of 50Hz.

The following data is considered:Effective magnetic cross section, Ae=41.2 mm2 Effective magnetic length, le=54.1 mmNumber of secondary turns, N=5000Winding Resistance, RW=150 Ohms Burden resistance, RL=22 OhmsBurden power factor angle β=0 degrees(Unity Power Factor)Primary current, Ip= 5 AFrequency, f=50 Hz

M A G N E T I C C O M P O N E N T S

Ferrite Material for Energy-MeterCurrent Transformer- T36

External Current Transformer (CT) driven Energy-meters have only alternating component as current input. Unlike whole current meters these are not subject to

DC superposition test.

By P. Mukherjee and S. Goswami, Epcos India

Table 1: Magnetic and Electrical Parameters

Values of T36

Parameters Condition Results

Initial Permeability 10 KHz; 0.25mT;25oC 6800

Variation from 10oC to 70

oC 10 KHz; 0.25mT +13% / -10%

Core loss factor (tand/mI x10-6

) 10 KHz;0.25mT;25oC

50 Hz; 5mT;25oC

#

3 67

Currie temp (oC) >130

oC

# Special measurement for Energy-meter application


The secondary current, Is=Ip/N=1 mAThe voltage across the secondary winding,

Es=Is*(RL+RW)= 0.172 V

The operating flux 0φ=Es/(4.44*f*N)=0.155 µWebers

This gives the operating flux density B0=φ0/Ae=3.76 mT,

clearly a low signal application.The measured relative permeability,

µI=6800 (Table 1)For single turn primary the inductance is the AL value of the ringcore. AL is related to the core factor and µI by: AL(nH)=0.4*π*µi*Ae(mm2)/le(mm) Eq. (1)From Eq.(1)

AL=6508 nHThe magnetizing primary current Im is given by :

Im =φ0/AL Eq. (2)

From Eq.(2), Im =24 mA

The loss current is given by,Ie = tanδ*Im Eq. (3)

At 50 Hz the measured tan δ/ µI = 67*10-6 (Table 1) tan δ= 6800*67*10-6=0.456

From Eq.(3), Ie= 11 mA

The ratio error pr as percent is given by:pr=100*(Imsinβ+Iecosβ)/Ip=0.22 Eq. (4)

The phase error θ in minutes is given by:θ=(180*60)*(Im*cosβ+Iesinβ)/(π*Ip) Eq. (5)

From Eq. (5) θ=16.4 minutes

The above results compare well with the limits of pr<0.5 andθ<30 minutes for a class 0.5 CT.The permeability vs temperature (µ-T) curve for T36 is shownbelow and it can be seen that any pronounced SPM peak between10oC and 70oC has been avoided. This material has been developed viewing at customer requirementfor external CT driven energy meter and this is no replacement forany existing Epcos material.

www.epcos.com

Figure 1: Permeability vs temperature curve of T36

m-T curve for T36

0

1000

2000

3000

4000

5000

6000

7000

8000

9000

10000

11000

12000

13000

14000

15000

16000

-50 -40 -30 -20 -10 0 10 20 30 40 50 60 70 80 90 100 110 120 130 140

Temp(oC)

pe

rme

ab

ilit

y

T36

just everywhere …

electronica Munich, Germany November 14 to 17, 2006Hall B5, Stand B5.506

For superior solutions: Inductors■ High current-handling capability■ High temperature range up to 150 °C■ Very compact designs■ Wide range of standard products

More information at www.epcos.com

We report the development of acapability based on the use ofa high bandwidth digitizer pack-

aged in a compact configuration where thesampled data is transmitted digitally usingTCP/IP network protocol. The system is bat-tery powered and heavily shielded to allowmeasurements to be made in regions ofextremely high field strengths. Connectionwith external instrumentation and controlsystems is accomplished by using only fiber-optic cabling, providing completely isolatedmeasurements.

Instrumentation of high voltage pulsedpower experiments can be problematicbecause of the strong (EM) fields presentaround the measurement location, and theneed to maintain isolation through the wallsof shielded enclosures. Isolation is importantto maintain measurement quality and toensure personnel safety.

Several approaches have been used tobuild specialized instrumentation to meetspecific requirements. Traditional methods ofinstrumentation involve placement of anoscilloscope inside a shielded container inclose proximity to the measurement point, orthe use of analog fiber-optic telemetry sys-tems to route the measurement signal to anexternal oscilloscope. In general the instru-mentation needs to measure the signal inthe time-domain, digitize the signal close tothe measurement point, offer the wide ana-log band-width, and be as small as possibleto minimize field perturbations. In responseto these requirements the Compact RemoteDigitizer or CRDAQ was developed and test-ed in comparison to the current pulsedpower measurement systems.

Compact Remote Digitizer Analog fiber-optic telemetry systems

require regular calibra-tion and careful treat-ment of fiber-opticcable and termina-tions. These restric-tions can be signifi-cantly reduced by digi-tizing the analog sig-nal at the source andtransmitting digitaldata via fiber. Thecompact remote digi-tizer (CRDAQ) seeksto lift these restric-tions. This system is afiber-optically coupled,battery-operateddevice contained in an EM-hardened casewith dimensions of 83.8" x 43.4" x 51.4".

The instrument is based on the 3UCompactPCI (cPCI) standard using commer-cial-off-the-shelf (COTS) computers and digi-

tizers. For this application the computer waschosen for low power consumption since theneed for computing power is minimal. Twodigitizers, a 250MHz and 1.5GHz model,

M E A S U R E M E N T

Fiber-Optically IsolatedInstrumentationPulsed / Power System Diagnostics

Advances in high sample rate/wide bandwidth analog-to-digital converters have enabledthe development of increasingly sophisticated instrumentation suited for the highly stress-

ing electro-magnetic environment associated with many pulsed power systems.

By Frank E. Peterkin, Benjamin M. Grady, Naval Surface Warfare Center, Dahlgren Virginia

Table 1 - CRDAQ specifications

Figure 1 - CRDAQ system block diagram


have been tested in the system. The250MHz digitizer or DC110 is a cur-rentproduct from Acqiris while the 1.5GHz(DC152) is new product developed through acooperative effort between NSWC andAcqiris USA. Table 1 presents a summarythe CRDAQ specifications and Figure 1shows block diagram.

CRDAQ consist of the electronic sub-assembly containing all of the system com-ponents in a single package and an enclo-sure into which the subassembly is insertedfor EM shielding. The electronic subassem-bly is designed to be removed from theenclosure and remain fully functional whileallowing access to the system componentsfor maintenance or repair. Figure 2 showshow the CompactPCI (cPCI) computer, digi-tizer, battery pack, and controller board(power conversion, communications, power

control, and system health) make up a selfcontained assembly. The hardware to con-tain the electronic subassembly consists of acustom designed part produced byStereolithography (SLA) that attaches to thecPCI backplane to make the self containedassembly. This complete assembly is theninserted into the shielded enclosure whichhas ST connections for fiber Ethernet, aSMA connector for the input signal, EMI airfilter for coo- ling, and a separate cover foreasy removal of the battery (Figure 3).

In order to keep the CRDAQ as efficientand compact as possible the controller boardis a simple two layer printed circuit boardpopulated with COTS components. UsingCOTS components reduces the depend-ence on extremely specialized circuits thusmaking maintenance and repair for the enduser easier (Figure The same statement istrue for the battery pack since it is comprisedof 4 Sony Lithium-Ion camcorder batteries

connected in series to produce the 28.8V 5.5amp hour pack.

Control of the CRDAQ is done using anyWindows XP/2000 based computer withEthernet by two pro- grams; one tocontrol/monitor the CRDAQ system via amicrocontroller and one to control and obtainthe data from the Acqiris digitizer. The micro-controller program monitors battery voltage,internal temperature, controls the attenuatorsetting, and provides for remote startup andshutdown to conserver battery life (Figure 5).The second program developed by Acqiris,AcqirisMAQS or Multichannel AcquisitionSoftware, provides a virtual window into thedigitizer for configuring the acquisitionparameters, arming the unit, and displayingthe digitized data which can be saved to a.le for further analysis at a later date (Figure 6).


Figure 2 - CRDAQ electronic subassembly Figure 4 - CRDAQ controller board

Figure 5 - CRDAQ control softwareFigure 3 - CRDAQ assembly process


Testing of both the 250MHz and 1.5GHzCRDAQ models has been performed withexceptional correlation with commercialmeasurement equipment. The DC110 or250MHz model was used in a recent fieldtest of a pulsed power source at the NSWCDahlgren MOATS test facility. In this test aEaton 91550- 2 150MHz current clamp wasused to measure the coupled current on apower cable with the DC110 CRDAQ and anEG&G ODT-E6 200MHz analog fiber trans-mitter. Figure 7 shows how well the CRDAQsignal is correlated with the EG&G signal.One significant observation is that the noisefloor of the CRDAQ is less than that of theEG&G.

The DC152 or 1.5GHz CRDAQ verifica-tion measurement was made in the laborato-ry where it was compared with a NanofastOP300 1GHz analog fiber link and a LecroyWavemaster 8300A using a Bournlea pulsegenerator. The signal from the Bournlea wassent through a 3-way power splitter to allthree instruments where a single pulse wassampled and used for comparison. In Figure8 it can be seen that the CRDAQ measure-ment is in agreement with the Lecroy oscillo-scope, used to directly digitize the signal, aswell as exhibiting less noise than theNanofast measurement system.

Literature

[1]"Technical Product Description, ModelsDC152 & DC122," Acqiris SA, Geneva,Switzerland, Apr. 2004.

Ben Grady received an AASET in 1987,BSEET from ODU in 1993 and a MSEE fromVirginia Tech in 2000. From 1986 to 1989 heworked as an Avionics technician, from 1990to 1994 he worked at NASA LangleyResearch Center as a MicrowaveTechnologist, and as a cellular base stationproduct engineer at Ericsson Telecom from1995 to 1997. Since 2000 he has been withthe NSWC Dahlgren Directed EnergyTechnology Office investigating the suscepti-bility of critical infrastructure systems tointentional EMI and developing pulsedpower/HMP measurement instrumentation.

www.acqiris.com


Figure 7 - CRDAQ 250MHz Measurement

Figure 8 - CRDAQ 1.5GHz measurement

Figure 6 - Acqiris MAQS software


Snap Shots of Product Innovation at

PCIM Nuremberg 2006LEM: Low-Profile, PCB-Mounting Transducer forCurrents up to 100ARMS

LEM has introduced the LAX 100-NP, aminiaturised PCB-mounting transducer forthe measurement of currents up to100ARMS. This Closed Loop Hall-effect sen-sor can be configured, by means of the pri-mary connections on the PCB, to measurecurrents up to 16.67, 25, 33.33, 50 or100ARMS. Its design simplifies integrationwith power modules in drive and inverterdesigns.

www.lem.com

ABB Switzerland Ltd: Extends the HiPak1 Series of IGBTModules.

ABB launched a new family of high power IGBT modules in the industry standard modulewith the popular 140 mm x 130 mm footprint. ABB uses its well-established SPT technology in

all HiPak modules. In particular, the high voltagechip-sets (2.5 – 6.5 kV) allow exceptionally highSafe Operating Area. Additionally, recourse to pas-sive clamping and snubbers has also been used toavoid costly de-rating. ABB’s HV SPT and SPT+planar chips require no such measures allowing fulldevice rating with efficient, hard switching.

www.abb.com/semiconductors

Bergquist: Thermal Plates Increase PackingDensity and Cut costs

The Bergquist Company has announced IsoEdge, a new range of heat sink products thatcan improve component packaging densities, reduce parts counts and cut the assembly costsof a wide range of electronic products. Available in custom and off-the-shelf configurations.

Intended in particular for use within power converter designs, IsoEdge thermal plates aremade using a powder-coating technology which confers a dielectric isolation of 2,250Vdc.

www.bergquistcompany.com

Power Integration:Reference Design Kitfor Multi-class Power-over-Ethernet

Power Integrations introduced a refer-ence design kit for Power-over-Ethernet(PoE) Powered Devices (PDs). The rapidgrowth of the PoE PD market ? expanding ata compounded annual growth rate of almost36 percent (Venture DevelopmentCorporation, June 2005) ? is being driven bythe wide adoption of network appliances,wireless LANs and Voice over InternetProtocol (VoIP) telephones.www.powerint.com.

P C I M I N N O V A T I O N S

www.bodospower.com50

Tyco Electronics: flowPIM 0 Optional withoutBreak-Chopper and with Enhanced Rectifier

The flowPIM 0 Family ( 3phase input rectifier, inverter, BRC and NTC) from Tyco is nowoptional available w/o break-chopper as well as enhanced input rectifier, with unchanged pin-out. Furthermore, the 600V module is now available like the 1200V module before in trenchfieldstop technology. This causes fewer switching and saturation losses in the application andleads to lower heat sink temperature or to higher out put power.

www.tycoelectronics.com

P C I M I N N O V A T I O N S

Micrel: Family ofUltra High-SpeedMOSFET Drivers

Micrel will showed itsMIC44F/18/19/20, a new family ofultra high-speed MOSFET drivers.The Company will also showcasedits recently introduced MIC2285,the industry’s first 8 MHz, 500mAsynchronous buck regulator forportable applications, whichmerges the best of LDO and buckregulator technology.

www.micrel.com

Mitsubishi: 3A/600V Module Using a New PowerChip TechnologyA super mini Dual In-line Package Intelligent Power Module (DIP-IPM Ver.4) with ratings of3A/600V has been developed by using a new power chip technology. As this technologywhich integrates FWD (Free Wheeling Diode) chip to IGBT chip in inverse parallel reduces ahalf of the power chip number in power module, this IPM makes reliability higher and handlingpower capability larger at same package size.

www.mitsubishichips.com

Semikron: Semitop 4 Brings More Power toExisting Range

Semikron expanded the Semitop family andthereby increases the power range with theintroduction of the Semitop 4 with a power capa-bility up to 22 kW motor power. The new mod-ules are available as three-phase IGBT and CIBmodules with currents up to 200A for 600V andup to 100A for 1200V modules. The Semitop 4will also be offered with the new Trench IGBTchip technology.

www.semikron.com

Texas Instruments:Electronics BoostWhite Goods’ EfficiencyBy Up To 30%

Three-phase asynchronous motorsiIncorporate FOC for quieter, faster andmore efficient white Goods at lower systemcosts. Tier Electronics LLC and TexasInstruments announced that TI’s digital sig-nal processing- (DSP) based TMS320C2000controllers are the key component in Tier’smotor control system for washing machinesand other white goods. System designersusing Tier’s Mini Universal Power Converter(UPC) can harness the processing powerand efficiency of TI’s C2000 controller.

www.ti.com


Texas Instruments announcedthe POLA alliance has agreed tooffer pin-compatible plug-in mod-ules based on TI’s T2 non-isolated,power modules with ultra-fast tran-sient response.

POLA alliance members, includ-ing Artesyn Technologies, EricssonPower Modules and Emerson’sAstec Power will develop and mar-ket the new plug-in modules withthe same functionality and form fac-tors as those provided by othermembers of the POLA alliance. Todate, POLA companies have manu-factured and introduced more than200 products with the same electri-cal designs to ensure full interoper-ability and true second sourcing.

Initially, the companies will sec-ond-source the 16-A and 30-A ver-sions of TI’s T2 series of point-of-

load modules thatprovide step-downDC/DC conversionfrom a wide 4.5 Vto 14 V input withadjustable outputvoltages down to0.7 V. POLA mem-bers will evaluateextensions to theT2 family as theyare released intoproduction.

Ideal for sup-porting 1-GHzprocessor-basedintermediate bus architecture (IBA)applications, the T2 modules offerseveral advanced features, such asTurboTrans technology, SmartSyncmodule-to-module synchronizationfunctionality and Auto-Tracksequencing feature. In addition, the

series of modules reduces the over-all power solution footprint by asmuch as 50 percent compared toTI’s previous generation devices.

www.ti.com/t2

POLA T2 Point-of-Load Modules

Isabellenhütte’s IKL series resis-tors are compact and calibratable,enabling users to make precisecurrent measurements from 10 Aup to 2000 A. The four wire resis-tors are completely pluggable, sothat a change-over in the measur-ing system for calibration purposescan be carried out easily andquickly. Depending on the model,resistor ranges are between 5 and100 µOhm, 100 µOhm to 1 mOhmor 1 mOhm to 1 Ohm. The use ofManganin resistor alloy means highaccuracy, +/- 0.05 %, which alsoguarantees a low temperaturecoefficient (< 10 ppm/K) as well ashigh time stability (< 0.05 %). Thelow thermal inner flow resistancecoupled with the high thermalcapacity, as well as the extremelylow thermal e.m.f. on copper enablethe measurement of very highimpulses on the one hand andenables the certain capture ofextremely small permanent currentsin the mA range on the other hand,

even immediately after a heavy cur-rent load. Typical applications forthe resistors are in calibration unitsfor electronic battery managementsystems in vehicles as well as inhigh current measurement systems.

The resistors are supplied with aDKD (German Calibration Service)calibrating certificate for the mostdemanding calibration measure-

ments. The relatively low change ofresistance over the temperaturecan even be compensated for by acalibrated Pt100 temperature sen-sor incorporated in the IKL-Hseries.

www.isa-asic.de

www.isabellenhuette.de

Calibration Resistors for Precise Current Measurements

N E W P R O D U C T S




The A8435 from AllegroMicroSystems Europe is a high-effi-ciency charge-pump white LEDdriver IC which combines excellentaccuracy and matching with flexibili-ty in dimming and control in a verycompact package.

The device, which is targeted atportable electronics display applica-tions, uses a proprietary 1´/1.5´control scheme to match up to fouroutput currents to within 0.5% LED.A low 1´/1.5´ transition voltagethreshold maintains optimum opera-tion in the 1´ mode for higher over-all efficiency, helping to prolong theoperating life of the lithium-ion bat-teries typically used in these appli-cations.

The A8435 operates over aninput range of 2.7 V to 5.5 V anddelivers up to 30 mA for each of thefour regulated current sources. Itcan deliver a total output current of120 mA, meeting the requirementsof most lithium-ion battery-poweredwhite LED backlight applications.Outputs can also be combined forflash or torch applications.

The devicealso offersflexibleoptions forLED currentdriving. TheLED currentcan be set byone of fourdifferentmethods:choosing anappropriatesetting-resist-ance value;two-bit paral-lel controlwith three lev-els; PWMcontrol; orone-wire seri-al pulse input to enable the partand set up to 11 dimming levelsfrom 100% down to 5%.

Comprehensive protection cir-cuitry includes short-circuit andovervoltage protection as well asthermal shutdown, while a soft-startfeature is used to limit the inrushcurrent.

The A8435 is available in a verylow profile 3 mm-square MLP-16package (A8435EES) with a thick-ness of only 0.75 mm.

www.allegromicro.com

Charge-Pump White LED Driver IC

Vicor announces the addition ofseven mid-power Micro DC-DCconverters to its high-density 24Vdcinput family: 50W models at 3.3, 5,12, 15, 24, 28, and 48Vout. Themodules — which incorporateVicor’s low-noise Zero-Current and

Zero-Voltage Switching (ZCS/ZVS)— are appropriate for power sys-tem applications in industrial andprocess control, distributed power,medical, ATE, communications,defence, and aerospace.

The addition ofthese modules dou-bles the size of thehigh-power density24Vin Micro family,which previouslyconsisted of 75W at3.3Vout and 100Wat 5, 12, 15, 24, 28,and 48Vout. Theconverters operatefrom 24V nominalinput, with an inputrange of 18V to

36V, and will operate down to 16Vafter startup. Efficiencies range upto 89% for the higher output volt-ages.

The modules, which are RoHScompliant (with F or G pin option),are 57.9 x 36.8 x 12.7mm in sizewith a height above board of10.9mm.

www.vicoeurope.com

Cost-Effective 24Vin Micro Modules



SynQor is proud to announce therelease of the PQ60033SGL20, thefirst in our fully 6/6 RoHS compliant,sixteenth brick DC/DC converterfamily. The PQ60033SGL20 has a

full 36-75V Telco input range andprovides an isolated 3.3V outputwith up to 66W of usable power ina 1.17in2 footprint. Using theDOSA standard pinout and foot-

print, the sixteenth brickuses 43% less board spacethan eighth brick convert-ers.

The PQ60033SGL20 uti-lizes a synchronous rectifi-cation topology to provideexcellent thermal perform-ance with a virtually flatderating curve. The moduleprovides the full rated cur-rent of 20A at 70C,200LFM – over 3A moreavailable current than othersixteenth bricks on themarket, and up to 4A morethan similarly rated eighthbricks.

The compact size of 1.3”x 0.9” frees up board real

estate for designs with limitedboard space. The low profile heightof 0.332” also makes the converteroptimal for applications with lowboard-to-board spacing constraints.

The 35-75Vin PQ60033SGL20 iscapable of withstanding transientson the input to 100V for 100ms,and has a basic isolation level frominput to output of 2000Vdc.Standard control features include+/-10% trim, remote sense, andremote on/off. The converter’sstandard protection features includeinput under voltage lockout (UVLO),output over voltage (OVP), overcurrent (OCP), over temperature(OTP), and short circuit protection.Operating temperature range is -40to +100degC.

www.synqor.com

Sixteenth Brick up to 66W

Micrel launched a new dual ultra-low dropout voltage (ULDO) linearregulator. The MIC5330 is part ofa new family of dual LDOs offeringultra low dropout voltage of75mV@300mA, more than 70dbpower supply ripple rejection(PSRR) and ultra low output noise.The part is offered in a tiny 2 mm x2 mm 8 pin leadless MLF packagemaking it ideal for today’s mostdemanding portable applicationsincluding cellular phone RF power,camera modules, imaging sensorsfor digital still and video cameras,PDAs, portable media players(PMP) and PC cameras. The IC iscurrently available in volume, withpricing starting at $0.66 for 1Kquantity.

The MIC5330 integrates twoindependently-controlled, high per-formance LDOs that offer excep-

tional transient performance whilerequiring only very small and inex-pensive 1uF ceramic capacitors.Both LDOs feature a low quiescentcurrent of 75µA per output, a fastturn-on time of 30µsec, current limitand thermal shutdown protection,

and can operate from -40°C to125°C.

www.micrel.com

Tiny Dual LDOs

Microchip announces a Web-based simulation tool for power-management applications. Knownas the Mindi simulation tool, thenew software enables designers toquickly generate detailed circuit dia-grams and specify associated pas-

sive components for a variety ofpower-supply and battery-chargerapplications. Circuits developed onthe web using the Mindi tool can bedownloaded to a PC and porteddirectly into system diagrams.

The Mindi simulation tool wasdesigned for engineers of all experi-ence levels. The software assistsdesigners in choosing system com-ponents by recommending a widerange of Microchip PIC microcon-trollers and analog products, basedupon the circuit. Being Web-based,the Mindi simulation tool providesreal-time updates ensuring that thelatest circuit developments andproducts are provided.

Applications supported by theMindi simulation tool include powersupplies such as DC/DC convertersfor handheld electronics devices,and battery chargers for recharge-able battery-powered devices.

Mindi is available for free onMicrochip’s Web site.

www.microchip.com/Mindi

Battery and Power Circuit Simulator

Puls Power Supplies announcesthe launch of the new UB10.241DC UPS. System power failures orvoltage fluctuations can damagevaluable equipment or machinesand cause expensive system down-time and loss of production. ThePuls UB10.241 together with a suit-able battery supply offers reliableand economical protection for24VDC systems.

The UPS input is isolated fromthe output to allow simple separa-tion of system elements that requireno-break power from non-criticalfunctions. This ensures that back-up time is not reduced by support-ing auxiliary circuits. Under normaloperation the system power supplycharges the UPS 12V battery,should the supply voltage drop or

be disconnected, the batteryvoltage is boosted to 24V viathe UPS and supplied to theload as a regulated powersource. On-board battery man-agement incorporates a “soft”battery charger, deep dischargeprotection and overload protec-tion to ensure long battery serv-ice life. Puls also offer a match-ing DIN-Rail battery module, theUKZ12.07 featuring a 12V 7AHmaintenance free lead acid bat-tery with on board fuse protec-tion for safety and isolation pur-poses and connecting cables tosuit the UB10.241 UPS.

DIN Rail DC UPS Eliminates Downtime

www.puls.co.uk/backup.php



Vacuumschmelze offers high-preci-sion current transformers for manu-facturers of electronic electricitymeters. A new revised productinformation sheet, including currenttransformers of the highly perme-able Vitroperm core material, whichreplace the old series of Ni-Fematerials, is now available. Thephase and amplitude error curvesdepending on the primary current

and temperature are given for everycomponent. Besides their applica-tion in electronic electricity metersthe de-scribed current transformersalso benefit other applications, e.g.precision meters and also otherfields such as installation and plantengineering.

www.vacuumschmelze.com

High Precision Current Transformers

Analog Devices unveiled theaddition to its iSensor family ofhighly integrated intelligent sensors,a low power, highly programmable

gyroscope that contains all of theembedded calibration, tuning, andcontrol functionality required todetect the rate at which a system is

rotating. The sin-gle-componentsolution, whichleverages AnalogDevices’ iMEMSMotion SignalProcessing tech-nology, requiresless than half thedesign space ofexisting multi-com-ponent discretesolutions, butoffers moreadvanced controlfunctionality.Using the iSensor

gyroscope, designers of industrialapplications where control is essen-tial – such as instrumentation, plat-form stabilization and navigation –can realize the benefits of inertialsensing in their systems at a lowercost and up to six-month fasterdevelopment times.

The gyroscope output is pre-cali-brated and indicates the rate atwhich the device is rotating.Depending on the applicationrequirements, the user can digitallyscale the sensitivity from +/– 80degrees per second to +/– 320degrees per second, with thedevice dynamic range scaling withit.

www.analog.com/isensor

Programmable MEMS Gyroscope

N E W S


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low-loss HiPak1 with SPT+

1200 – 6500 V IGBTs

duals, singles, choppers, diodes

up to 10.2 kV isolation

SPT with astronomic SOA

Industry standard module 130 x 140 mm

... and coming soon to a planet near you:

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Documents

ZKZ 64717 7-06 Bodo´sBodo´sPower Systems · designer to quickly optimize designs and monitor real-time system performance. "The expanding Di-POL product line offers flexibility,