In each issue of How2Power Today, experts from industry and academia present the latest design techniques and solutions for power conversion in a wide range of applications. In this section, we provide some background on these authors.
Evgenije M. Adžić
Evgenije M. Adžić received the Dipl.-Ing and M. S. degrees in electrical engineering from the Faculty of Technical Sciences, University of Novi Sad, Novi Sad, Serbia in 2005 and 2007, respectively. In 2005, Evgenije joined the Faculty of Technical Sciences, University of Novi Sad, Serbia and since September 2007, he has been a Ph.D. student at the Chair for Power Electronics and Electrical Machines at University of Novi Sad. In 2010, Evgenije joined Typhoon HIL in Novi Sad where he currently serves as director for Power Electronics Application Engineering and Quality Assurance Group. His interests are in the field of power electronics, renewable energy sources, and ultra-low-latency hardware-in-the-loop systems.
Dr. Sunil Akre
Sunil Akre, a senior member of the technical staff, joined Maxim Integrated Products in 2006. Prior to joining Maxim he Worked for C&D Technologies and Martek Power Abbott, both in the U.S., as well as for Alpha Technologies in Canada, Artesyn Technologies in Ireland, Siemens A.G. in Germany, Advanced Microcomputers in Singapore, and Aditya Power Systems in India. In 2003 he earned a Ph.D. in Power Electronics from the University College in Cork, Ireland and in 1986, an undergraduate Degree in Electronics & Telecommunications from Govt. College of Engineering in Pune, India.
Articles written by Dr. Sunil Akre in How2Power Today:
Small-signal Analysis, Modeling and Design of a Synchronous Buck-Converter in Voltage-Mode Control
Don Alfano
Don Alfano serves as director of power products at Silicon Laboratories. Prior to Silicon Laboratories, Don was co-founder and vice president of marketing for Cygnal Integrated Products, which was acquired by Silicon Laboratories in 2003. Prior to founding Cygnal, he worked for TelCom Semiconductor, an analog and mixed-signal IC supplier, where he served as director of marketing and director of applications. Previously, Don served as vice president of marketing for NVE, Eastern area manager for Dallas Semiconductor and field applications engineer for Mostek. He has also held design engineering positions for analog and digital control equipment and telecommunication systems. Don holds a master’s degree in electrical engineering from Villanova University.
Articles written by Don Alfano in How2Power Today:
Digital Isolators: A Space-Saving Alternative to Gate-Drive Transformers in DC-DC Converters
C. Appere
Cédric Appere joined STMicroelectronics in Tours, France in 2000 and currently serves as a telecom application engineer. Cédric is a graduate of Ecole Centrale d'Electronique.
Integrated Protection and Careful Layout Protect PoE Systems from EOS and ESD
Hector F. Arroyo
Hector F. Arroyo holds a BSEE degree with a major in Electronics and Communications from the Monterrey Institute of Technology (ITESM) in Mexico City. Hector joined National Semiconductor in 1997 and since then has held various positions in the applications, sales and technical marketing areas. Since 2005 he has been a senior field applications engineer and a staff field applications engineer in San Diego for local southern California markets as well as for Latin America on selected technologies such as LED lighting.
Articles written by Hector F. Arroyo in How2Power Today:
Tapped Inductors Enable Simple, Compact Buck-Boost Converters With Single Noninverting Or Dual, Complementary Outputs
Agasthya Ayachit
Agasthya Ayachit received his B.E degree in Electrical and Electronics Engineering from Visvesvaraya Technological University, India in 2009 and M.S degree in Electrical Engineering from Wright State University in 2011. Currently, he is working as a lecturer at Penn State Erie—The Behrend College. His research interests are in resonant and PWM dc-dc power converters, modeling and control of dc-dc converters, and energy harvesting.
Articles written by Agasthya Ayachit in How2Power Today:
Power Electronic Circuitry In LED Modules: An Overview
Nikola L. Čelanović
Nikola L. Čelanović received a B.S. degree in electrical engineering from the University of Novi Sad in 1995, an M.S. degree in Mechanical Engineering from Vanderbilt University, Nashville, Tennessee in 1996 and a Ph.D. degree from Virginia Polytechnic Institute and State University in 2000. From 2000 to 2005 Nikola was with the ABB Research Centre in Baden-Dättwil, Switzerland and from 2005 to 2008 with the ABB Drives Development Department, Turgi, Switzerland. Since 2008 Nikola has been the CEO and co-founder of Typhoon HIL in Baden, Switzerland.
Alan Ball
Alan Ball has 35 years experience in switching power supply design and analysis. His career has encompassed both military and commercial power supply design. For the past fifteen years, Alan has been involved with applications support for semiconductor products, working for ON Semiconductor where he has held various application engineering positions. Alan is currently the technical director of engineering for the Digital Consumers Group at ON Semiconductor. Previously, Alan worked for Power Paragon as an engineering manager and general manager of the Airborne Power division. He holds a BSEE from Arizona State University, and an MBA from Keller Graduate School of Management. Alan holds approximately 25 patents.
Maximize The Efficiency Of Induction Heating By Minimizing IGBT Losses
Christophe Basso
Christophe Basso is an Application Engineering Director at ON Semiconductor in Toulouse, France. He has originated numerous integrated circuits among which the NCP120X series has set new standards for low standby power converters. SPICE simulation is also one of his favorite subjects and he authored a second book, “Switch-Mode Power Supplies: SPICE Simulations and Practical Designs”, published by McGraw-Hill in 2008. His work was positively reviewed in several magazines and in a recent PELS newsletter. Christophe holds a BSEE-equivalent from the Montpellier University, France and a MSEE from the Institut National Polytechnique de Toulouse, France. He holds 17 patents on power conversion and often publishes papers in conferences and trade magazines.
Articles written by Christophe Basso in How2Power Today:
Ali M. Bazzi received the B.E. degree in electrical engineering in June 2006 (with high distinction), and the M.E. degree in electrical engineering in July 2007 from the American University of Beirut, Lebanon. Since August 2007, he has been pursuing the Ph.D. in electrical engineering at the University of Illinois at Urbana-Champaign.His research interests are power electronics applications in motor drives and renewable energy, mainly in the fields of control and optimization. He was the conference director of the 2010 Power and Energy Conference at Illinois, and is currently the chair of the IEEE PELS/PES joint Student Chapter at the University of Illinois at Urbana-Champaign. He is a student member of the IEEE, and a member of the IEEE Power Electronics Society, and IEEE Industry Applications Society, and IEEE Power and Energy Society.
Articles written by Ali M. Bazzi in How2Power Today:
Comprehensive Flux Estimator Implementation Procedures For Advanced Control Of Inverter-Fed Induction Machines
Bob Bell
Robert (Bob) Bell is the applications engineering manager for the National Semiconductor design center in Phoenix, Ariz. Products designed at the Phoenix design center include integrated switching regulators, next-generation PWM power controllers, gate drivers, and hot-swap and load-share controllers. He has been with National Semiconductor since September 2001. Prior to joining National, Bob designed power converters for military and space applications. Bob holds a Bachelor of Science degree in Electronic Engineering from Fairleigh Dickinson University. To date he has published 25 power design articles, 8 conference papers and 3 patents.
Frequency Dithering: A Tool for Overcoming Last-Minute EMC Hurdles
Dakshina Murthy Bellur
Dakshina Murthy Bellur received his BE degree in electrical engineering from Visveswaraiah Technological University, Belgaum, India, and MS from Wright State University, Dayton, OH in 2003, and 2006, respectively. He is currently pursuing PhD at Wright State University. His areas of interest are PWM dc-dc converters, resonant power converters, high-frequency magnetics, and renewable energy systems.
Articles written by Dakshina Murthy Bellur in How2Power Today:
An Overview and Simulation of DC-DC-AC and Z-Source Grid Connected Inverters
Ashok Bindra
Ashok Bindra is a veteran writer and editor with more than 25 years of editorial experience covering RF/wireless technologies, semiconductors and power electronics. He has written, both for print and the web, for leading electronics trade publications in the U.S, including Electronics, EETimes, Electronic Design and RF Design. Presently, he has his own technical writing company called Technika through which he does writing projects for different trade publications and vendors. Prior to becoming an editor, Bindra worked in industry as an electronics engineer. He holds an M.S. degree from the Department of Electrical and Computer Engineering, Clarkson College of Technology (now Clarkson University) in Potsdam, NY, and an M.Sc (Physics) from the University of Bombay, India. He can be reached by email at bindra1[at]verizon.net.
Carl Blake
Carl Blake is vice president of marketing at Transphorm. Blake began his career with Raytheon as a power systems design engineer, gaining experience in power supply, RF and logic design. Over the next 19 years, he progressed through many levels of the organization before moving to the semiconductor industry in 1991, bringing customer understanding to the new product definition process. Blake has successfully launched hundreds of new products and technologies in the power industry. In addition, he served as co-chair of the Technology Roadmap committee of the Power Sources Manufacturers Association (PSMA), and was recently elected as PSMA president. Blake received his Bachelor of Science degree in Electrical Engineering summa cum laude at the University of New Haven.
Articles written by Carl Blake in How2Power Today:
GaN Power Devices Slash Size, Raise Efficiency Of 4-kW Solar Inverter
Cyril Borchard
Cyril Borchard is a product marketing engineer responsible for rectifiers in the power segment at STMicroelectronics, France. He was previously in charge of marketing activities for rectifiers, protections, IPAD, thyristors and triacs in the consumer segment. In that scope, Cyril Borchard participated as marketing representative in the development of dedicated rectifiers for flat-panel displays (LCD and PDP) as well as specific protections and IPAD for consumer applications such as HDMI. Cyril Borchard holds a degree in Microelectronics and Automation from the Ecole Polytechnique de Montpellier.
Articles written by Cyril Borchard in How2Power Today:
PFC Efficiency Improvement Using SiC Power Schottky Rectifiers
Vipin Bothra
Vipin Bothra is product marketing manager at STMicroelectronics based in Schaumburg, Ill. Over the years Vipin has held many roles at ST in application, marketing and technical marketing. He holds an MBA from the Kellogg School of Management and a Bachelors degree in Electrical Engineering from VNIT, India. Vipin’s technical experience includes designing various applications in power conversion such as digital power supplies, drivers for LED lamps, high-efficiency solar inverters and PFCs. The Triac-dimmable offline LED driver was developed by Vipin and his team and received a patent in 2008. Vipin has authored many publications in technical publications around the world and has actively participated in many regulatory and standard-setting bodies in the U.S.
Articles written by Vipin Bothra in How2Power Today:
Process, Packaging Combine To Advance High-Voltage Power MOSFETs
John Bottrill
John Bottrill is a senior applications engineer at Texas Instruments in Manchester, NH. John supports customers and evaluates new ICs before release. In doing so, he has produced more than 20 technical papers and has two patents to his credit. He received his B. Sc. in Electrical Engineering from Queen’s University at Kingston, Ontario, Canada. You can reach John at ti_johnbottrill@list.ti.com.
Articles written by John Bottrill in How2Power Today:
Don't Let Jitter Shake Up Your Flyback Converter Designs
David Bour
David Bour, chief scientist and head of MOCVD at Avogy has worked for nearly 30 years on semiconductor electronics and optoelectronics, and metal organic chemical vapor deposition, including UV-blue-green GaN-based LEDs and laser diodes, red AlGaInP lasers, telecommunication devices, strained quantum well lasers, mid-IR quantum cascade lasers, heterojunction bipolar transistors, and photovoltaic devices. Before Avogy, Bour was the chief technology officer of Applied Materials’ Solid State Lighting Division and held positions at BridgeLux, Xerox Palo Alto Research Center’s Electronic Materials Laboratory, Alta Devices, and Agilent Laboratories. Bour received a B.S. degree in Physics from MIT in 1983 and a Ph.D. degree in Electrical Engineering from Cornell University in 1987. His research is documented in more than 200 publications and 90 U.S. patents; and he is a fellow of the IEEE, for contributions to the growth and understanding of quantum well lasers.
Articles written by David Bour in How2Power Today:
Vertical Devices In Bulk GaN Drive Diode Performance To Near - Theoretical L imits
Oliver Brennan
Oliver Brennan is a senior IC design engineer with Analog Devices where has worked for 12 years. He currently works on Power Management Products. Previously, Oliver worked on data converters.
Articles written by Oliver Brennan in How2Power Today:
Switching-Regulator Insights: Achieving Longer Battery Life in DSP Systems
Frank Cathell
Frank Cathell has been a senior applications engineer with ON Semiconductor for over 6 years. Frank has worked in the power electronics industry for over 35 years and has obtained several patents for power conversion circuits and has written numerous articles and/or papers on the subject. Frank’s previous employment has included Lambda Electronics, International Power Systems, Maxwell Laboratories, Tectrol Inc. and others in addition to his own past consulting business.
Articles written by Frank Cathell in How2Power Today:
Power Supply Topology Selection – It’s Not Just About Power
Arthur Chiang
Arthur Chiang currently holds the position of director of reliability engineering for Vishay Intertechnology. He is a member of IEEE, AEC, JEDEC, and EDFAS, and holds numerous patents in emission microscopy and power diodes. Mr. Chiang holds an M.S. in electrical engineering from Stony Brook University and a Ph.D. in electrical engineering and computer science from Princeton University.
Articles written by Arthur Chiang in How2Power Today:
Failure Analysis On Power MOSFETs With Copper Wire Bonds
Vijay Choudhary
Vijay Choudhary is an applications engineer at National Semiconductor’s Phoenix Design Center. At National Semiconductor, Vijay has worked on wireless charging and power management ICs for mobile devices. He currently works on isolated and nonisolated switching converters for industrial applications. Vijay has a Bachelor of Technology from Indian Institute of Technology, Kharagpur, and a Master of Science and PhD from Arizona State University. Vijay has written several papers, application notes, and articles in the field of power management.
Articles written by Vijay Choudhary in How2Power Today:
Simple Stepdown Regulator Generates Multiple Voltage Rails With Good Efficiency and Regulation
Steve Clemente
Steve Clemente joined International Rectifier (IR) in 1980, after working in the Numerical Control Division of General Electric and the Corporate R&D of Westinghouse. In his 30+ years at IR, Clemente has held several managerial positions in Applications, R&D and Systems Engineering.
Articles written by Steve Clemente in How2Power Today:
Enhanced Web Tool Speeds IGBT Selection, Matching Device To The Application
Mala D. M.
Mala D. M. currently holds the position of hardware engineer for Strategic Technology Group. She has a B.E. in Electrical and Electronics and M.Tech in Power Electronic Systems and controls from Manipal University. She has teaching experience in power electronics. Her interests include design and firmware development of permanent magnet motor control for electric vehicles, switch-mode power supplies, simulation, and electromagnetic design and analysis.
Articles written by Mala D. M. in How2Power Today:
Selecting A DSP Controller For Brushless Permanent Magnet Motor Drives
Barry Dagan
Barry Dagan, P. E. is chief technology officer of Cool Innovations. Barry has more than 25 years of experience in thermal management design and holds multiple patents in this area.
Articles written by Barry Dagan in How2Power Today:
Flared Pin Fin Heat Sink Keeps LED Light Burning Brightly
Pierre Delatte
Pierre Delatte is CTO and one of the co-founders of CISSOID. With 15 years of experience in high-temperature integrated circuit (IC) design, he is in charge of the technical development and vision of the company. Delatte is also in charge of advanced R&D programs at Cissoid. Delatte holds a Master of Science in Electrical Engineering from Université Catholique de Louvain.
Articles written by Pierre Delatte in How2Power Today:
Designing Power Converters For 100°C+ Environments: Why Use 225°C-Rated Power Components?
Rakesh Dhawan
Rakesh Dhawan is a twenty years veteran of Power Electronics Industry. Rakesh has a BTech in Electrical Engineering from the Indian Institute of Technology, Kharagpur, a Masters’ of Electrical Engineering (MSEE) from the University of Minnesota, and an MBA from Old Dominion University, Virginia. Rakesh has been an entrepreneur who has built several high-quality technology businesses. Rakesh has six approved and filed patents and twenty five conference and journal publications to his credit. Rakesh founded Strategic Technology Group to further his passion in power electronics. His interests include electric bicycles, electric vehicles, permanent magnet brushless motor drives, switch-mode power supplies, solar inverters, simulation, statistics, project management and new and ultra-fast product development. Rakesh has built and managed several high-technology product development teams in his career. He has been directly responsible for over twenty five product launches.
Articles written by Rakesh Dhawan in How2Power Today:
Integrating Statistics and Manufacturing Data into Simulation of Permanent Magnet Motor Drives
Giuseppe Di Stefano
Giuseppe Di Stefano is a technical marketing manager in the Industrial & Power Conversion Business Unit of STMicroelectronics. He is based in Catania (Italy). Di Stefano joined the company in 1982 and covered different roles inside ST: application engineer for small-signal and medium-power transistors, hardware development engineer for advanced testing, marketing engineer for automotive smartpower devices, and finally technical marketing manager for intelligent power switches (IPS) for industrial. He is the author of several technical articles concerning smartpower devices, presented in international conferences and technical magazines.
Articles written by Giuseppe Di Stefano in How2Power Today:
Use Intelligent High-Side Power Switch To Satisfy Safety Requirements In Process Control And Industrial Automation
Cristian Dinca
Cristian Dinca received his Diploma degree and Master’s degree in electronic and engineering from the University Politehnica Bucuresti, Romania in 2006 and 2008. Cristian Dinca is currently working at ON Semiconductor Romania as an analog IC designer dealing with low dropout regulators.
Articles written by Cristian Dinca in How2Power Today:
Internal LDO Circuit Offers External Control Of Current Limiting
Kelly Ding
Kelly Ding joined Integrated Device Technology (Shanghai) Co., Ltd. in 2002 and now serves as a marketing manager. Kelly holds B.S. degrees in English of science and technology as well as computer science from Shanghai Jiao Tong University.
Articles written by Kelly Ding in How2Power Today:
Energy Meter Design Operates Accurately Over Wide Current Range
Lisa Dinwoodie
Lisa Dinwoodie is an applications engineer at Texas Instruments where she supports customers, evaluates new ICs before release, and designs evaluation modules for customer use. Lisa has more than 16 years in the power supply design industry. She received her B.Sc. in Electrical Engineering from Northeastern University in Boston, Massachusetts. You can reach Lisa at ti_lisadinwoodie@list.ti.com.
Articles written by Lisa Dinwoodie in How2Power Today:
Primary-Side Current Monitoring Won’t Stop Overcurrents In DCM-Operated Flybacks
Don Disney
Don Disney is the senior director of technology and product development at Avogy. He received his BSEE from Kettering University and PhD EE from Stanford University, and subsequently has held senior engineering and management positions at Delco Electronics, Power Integrations, Advanced Analogic Technologies, and Monolithic Power Systems. Disney’s contributions to the field of power semiconductors span many technologies, including silicon-on-insulator power devices, IGBTs, high-voltage integrated circuits, Bipolar-CMOS-DMOS, and power MOSFETs. He has authored several IEEE papers and more than 100 U.S. patents.
Articles written by Don Disney in How2Power Today:
Vertical Devices In Bulk GaN Drive Diode Performance To Near - Theoretical L imits
John Dunn
John Dunn is a licensed professional engineer in the State of New York. He has had over forty-five years of design experience in services to over a dozen military and industrial corporations in multiple electronic disciplines including analog (low noise audio, power audio, temperature measurement, electrocardiogram recordings, etc.), power supplies (low voltage to 100 A and high voltage to 100,000 V), HF/VHF/UHF equipment, uP development and debugging, test instrument design and test program development. John has had more than forty technical items published in the trade journals. Items appearing in Electronic Design Magazine's "Ideas For Design" column won their "Best Of The Issue" award on four occasions. John is also the founder of the LinkedIn group Analog Developments and has lectured adult classes in mathematics and in electronics theory.
Use Exponential Equations And A Simple Program To Solve Power Supply Problems
Andrew Edwards
Andrew Edwards is simulation and modeling manager at Avogy and has been involved with GaN since 1994. Prior to Avogy, Edwards was a device engineer at International Rectifier and before that, at Nitronex. Andrew has a bachelor’s degree from Virginia Tech, and masters and Ph.D. from George Mason University. Edwards also served as a postdoctoral researcher at the Naval Research Laboratory in Washington D.C.
Articles written by Andrew Edwards in How2Power Today:
Vertical Devices In Bulk GaN Drive Diode Performance To Near - Theoretical L imits
Harold Eicher
Harold Eicher is VP of engineering at Champs Technologies, a company which he founded in 2005. In this role he has designed planar magnetics for telecom, industrial, computer and avionics markets. From 1985 to 2005, Eicher was the VP of engineering at Magnetico, which he also founded. At Magnetico, Eicher designed and developed magnetics and electronics for avionics, military, and space satellite markets. Eicher sold this company in Dec 2003 to Standex Electronics, but continued consulting through June 2005. Previously, Eicher was an engineer at AVM where he performed magnetics design and field application engineering. Eicher studied at Boston College where he obtained an AB degree in economics and political science, and then studied law, receiving a JD degree in 1979 from the Saint Louis University School of Law.
Articles written by Harold Eicher in How2Power Today:
Embed Your Planar Magnetics To Maximize DC-DC Converter Performance (Part 1)
Anthony Esposito
CEO and owner of Avatar Engineering Corporation, Anthony Esposito, has over
30 years of experience in power conversion and precision instrumentation for
all markets; consumer, industrial, telecommunications, green-power, medical,
military, and space. Present activities include new semiconductor research,
high-efficiency converters for military and fuel cell applications, and
RF-thermal therapy systems for treatment of cutaneous cancer and other
malignancies. Prior work includes medical MRI gradient amplifier and
systems design, telco cell site power systems design, as well environmental
controls design for NASA's original Enterprise Shuttle. The New Product
Development (NPD) software, "EQuote" (short for Engineering Quote) has been
used extensively by the SBA and Harvard Business. Mr. Esposito resides in
Arizona, is degreed in electrical engineering, business, and computer
science, has numerous patents in power controls and communications, and
often mentors young engineers from ASU on the joys of analog design and
entrepreneurship.
Articles written by Anthony Esposito in How2Power Today:
Synergy: SEPIC-Cuk Combo Illustrates Benefits of Creative Thinking
Andrew Ferencz
Andrew Ferencz received his SB and SM degrees from MIT in 1987 and 1989. He was previously the VP, Technology at Galaxy Power in Westborough, Mass., developing high power density dc-dc converters. Prior to that, Andrew was the VP, Engineering at Acumentrics in Westwood, Mass. For the last eighteen months he has been self-employed, working on various projects as a turnkey design engineer and consultant in the medical, military, commercial, and industrial markets.
Articles written by Andrew Ferencz in How2Power Today:
Magnetically Isolated Digital Coupling Circuit Solves Gate Drive and Communications Dilemmas
Dennis Feucht
Dennis Feucht has been involved in power electronics for 20 years, designing motor-drives and power converters. He has an instrument background from Tektronix, where he designed test and measurement equipment and did research in Tek Labs. He has lately been doing current-loop converter modeling.
Articles written by Dennis Feucht in How2Power Today:
Rediscovering The Integrated-Magnetics Isolated Ćuk Topology
Randy Frank
Randy Frank has more than 30 years of industry experience in electronics and semiconductors at companies that include Chrysler, Motorola and International Rectifier, where he was involved with product engineering, marketing and applications. At American Motors, now part of the Chrysler Group LLC, he was responsible for implementing their first electronic engine control systems. Randy was the product manager for SMARTMOS ICs at Motorola, now Freescale Semiconductor, when its first power ICs were introduced. He has written on a variety of topics from power semiconductors and ICs to microcontrollers and digital signal processors. Randy is a Society of Automotive Engineers (SAE) Fellow and an IEEE Fellow. He has an MSEE, MBA and BSEE from Wayne State University in Detroit, MI.
Dave Freeman
David Freeman is a Texas Instruments Fellow and engineering manager in Texas Instruments’ Power Management business unit where currently he manages TI’s Solar Energy Systems Lab. This lab focuses on methods that increase the delivered power from solar energy systems as well as provide monitoring and management for improved reliability and safety. David’s 35-year career has always focused on energy sources and energy management. David is a popular expert in his field who has presented at many conferences around the world, including in the U.S., China and Japan. He has written multiple technical papers and a monthly column in a publication targeted to electrical engineers. Many patents in battery technology and power management have been credited to David’s efforts. David has a BS degree in physics from Midwestern University. He can be reached at ti_davefreeman@list.ti.com.
Articles written by Dave Freeman in How2Power Today:
Solar Microconverter Implements Novel MPPT Algorithm
Giovanni Frezza
Giovanni Frezza joined STMicroelectronics in 1999 after he received a Master of Science Degree in physics from the University “La Sapienza” of Rome, Italy in 1998. After several years working on MEMS, advanced packaging and sensors as R&D team leader, he focused on industrial application-specific products in the Technical Marketing organization. Today, he is a technical marketing manager in the Americas region based in Schaumburg, Illinois, USA.
Articles written by Giovanni Frezza in How2Power Today:
System-On-Chip Architecture Raises Performance Of Microstepping Motor Driver Designs
Veda Prakash Galigekere
Veda Prakash Galigekere received the B.E, M.S Degrees from Visveswaraiah Technological University, Belgaum, India and Wright State University, Dayton, Ohio in 2004 and 2007, respectively. He is currently pursuing his PhD at Wright State University. His areas of interests are PWM dc-dc and dc-ac inverters, power semiconductor devices, renewable energy systems and system-level simulations of the same.
Articles written by Veda Prakash Galigekere in How2Power Today:
An Overview and Simulation of DC-DC-AC and Z-Source Grid Connected Inverters
Frederic Gautier
Frederic Gautier is an application engineer at STMicroelectronics, France. He has been an expert in switched-mode power supply applications and the industrial and power segments within the Application & System Engineering department since 1998. Frederic Gautier graduated with a technical degree in electronics and holds several patents in the switched-mode power supply domain within STMicroelectronics.
Articles written by Frederic Gautier in How2Power Today:
PFC Efficiency Improvement Using SiC Power Schottky Rectifiers
Profirescu Ovidiu George
Profirescu Ovidiu George is a design engineer at ON Semiconductor Romania, with seven years of experience in design, verification and validation of analog integrated circuits. He has actively participated in the development of several LDO product families. George is also involved in academic activities as an assistant professor at the University Politehnica of Bucharest, Electrical Engineering Department where he teaches Electronic Devices and Circuits, TCAD, Device and Process Simulation, using industry-standard simulators and equipment. George graduated from the University Politehnica of Bucharest in 2006 as an “Advanced Microelectronics” Master and also from the University Politehnica of Bucharest in collaboration with Infineon Technologies in 2008. Since 2007 George has been a PhD student.
Peter Green
Peter Green received a BSc degree in electrical engineering from Queen Mary College, University of London in 1985. Since then he has worked in product design and development for commercial and military companies in the power supply and lighting industries in the UK. He is a member of the Institution of Engineering and Technology and a Chartered Engineer. In 2001 he relocated to California to join the Lighting Design Center at International Rectifier where he has worked on new lighting ASIC definition and design, as well as application support. Peter is currently managing LED systems and applications. Peter has previously presented at APEC, PCIM and many other conferences and has several patents related to lighting electronics.
Paul Greenland
Paul Greenland is a power industry veteran with over thirty years’ experience in the design, application and marketing of power conversion systems. His designs range from dc-dc converters in the first cellular phones to ion propulsion systems in satellites. Paul is an avid radio amateur, dedicated to the proliferation of power electronics know-how across a wide variety of applications.
Articles written by Paul Greenland in How2Power Today:
Understanding Industrial System Structures Is Key To Powering Them
Varun Kumar H
Varun Kumar H received his Bachelor’s of Engineering from Visvesvaraya Technological University, Belgaum, India in 2009. He has his MTech from MIT, Manipal University, Manipal, India, in Power Electronics Systems and Control. He is currently working as a hardware and simulation engineer at Strategic Technology Group, Pune, India. His areas of interests are power semiconductor devices, motor drives and control, and OrCAD/PSPICE (system-level simulations.)
Articles written by Varun Kumar H in How2Power Today:
Selecting A DSP Controller For Brushless Permanent Magnet Motor Drives
Chad Hall
Currently serving as chief operating officer of Ioxus, Chad Hall has used his extensive mechanical engineering and business experience to take Ioxus from funding to factory to launch. Chad is responsible for manufacturing and testing of standard products, as well as further establishing the company and building the team, increasing sales, locating funding, and spurring continued product development. Chad is also responsible for educating the market on Ioxus products and training sales personnel on the technical aspects of the expanding product line.
Chad spent 14 years with Ioxus’ parent company, Custom Electronics, Inc. (CEI). In addition, he has been involved in several high-voltage, high-reliability capacitor projects at national labs. Chad attended State University of New York, Delhi and received a 3-M certificate in electro-mechanical design and drafting. Chad is a member of the American Society of Mechanical Engineers (ASME).
Ajay Hari is an Applications Engineer at the National Semiconductor design center in Phoenix, Arizona. He has been with National Semiconductor since 2007. Prior to National, he worked for General Electric designing power converters for lighting applications. He holds a Master’s in Electrical Engineering from the University of Florida. Ajay has published several papers and articles in the area of power electronics and holds one U.S. patent.
Frequency Dithering: A Tool for Overcoming Last-Minute EMC Hurdles
Sanjay Havanur
Sanjay Havanur is currently the principal applications engineer at Alpha & Omega Semiconductor, Inc. Since receiving his Master's Degree in Power Electronics and Drives at the Indian Institute of Technology, Mumbai in 1983, Havanur has gained extensive experience in the field of power electronics, having worked in design and applications in both India and the U.S.
He has published papers and application notes in technical journals, and holds several patents relating to high-frequency power conversion. Sanjay Havanur's current interests include novel and efficient power conversion topologies, energy harvesting techniques and solar power.
Articles written by Sanjay Havanur in How2Power Today:
Timothy Hegarty is a principal applications engineer for the National Semiconductor design center in Tucson, Ariz. He received the B.E.(Elec.) and M.Eng.Sc degrees in Electrical Engineering from University College Cork, Ireland in 1995 and 1997, respectively. Prior to joining National, he worked for Artesyn Technologies designing isolated board-mounted brick converters. His areas of interest are integrated PWM switching regulators and controllers, LDOs, references, hot-swap controllers, renewable energy systems, and system-level simulation of same.
Articles written by Timothy Hegarty in How2Power Today:
SIMPLIS Simulation Tames Analysis of Stability, Transient Response, and Startup For DC-DC Converters
Richard K. Hester
Dick Hester currently works on solar power module electronics for Texas Instruments Power Management group. Dick has over three decades of experience working on everything from circuits and subsystems for analog interfaces to DSP-based systems. He received a PhD in physics from The College of William & Mary, Williamsburg, Virginia, and was a post-doc in the Chemistry Department of MIT. He has been active in the IEEE in various capacities and was elected IEEE Fellow in 1994 and TI Senior Fellow in 2002. He can be reached at ti_dickhester@list.ti.com.
Articles written by Richard K. Hester in How2Power Today:
Solar Microconverter Implements Novel MPPT Algorithm
Jun Honda
Jun Honda is a senior staff engineer in International Rectifier’s Energy Savings Product Business Unit in El Segundo, Calif. Jun has more than 15 years of experience in designing consumer, as well as professional audio circuits, including class D audio amplifiers.
Integrated Driver Shrinks Class D Audio Amplifiers
Yueqaun Hu
Yuequan Hu received the Bachelor’s and Master’s degrees in Mechanical Engineering, and Ph.D. degree in Electrical Engineering from the University of Science and Technology of China in 1989, 1992, and 1999, respectively. From May 2003 to Oct. 2010, he was a member of R&D staff at the Power Electronics Laboratory, Delta Products Corporation, Research Triangle Park, North Carolina, the Advanced R&D unit of Delta Electronics, Inc., Taiwan, one of the world’s largest manufacturers of power supplies. He is currently with Cree Inc., working on R&D of LED lighting solutions. His main research interests include high-intensity discharge (HID) lamp ballasts and LED lighting.
Laszlo Huber
Laszlo Huber was born in Novi Sad, Yugoslavia, in 1953. He received the Dipl. Eng. degree from the University of Novi Sad, Novi Sad, the M.S. degree from the University of Niš, Niš, Yugoslavia, and the Ph.D. degree from the University of Novi Sad in 1977, 1983, and 1992, respectively, all in electrical engineering.
From 1977 to 1992, he was an Instructor at the Institute for Power and Electronics, University of Novi Sad. In 1992, he joined the Virginia Power Electronics Center at Virginia Tech, Blacksburg, as a Visiting Professor. From 1993 to 1994 he was a Research Scientist at the Virginia Power Electronics Center. Since 1994, he has been a Senior Member of the R&D Staff at the Power Electronics Laboratory, Delta Products Corporation, Research Triangle Park, North Carolina, the Advanced R&D unit of Delta Electronics, Inc., Taiwan, one of the world’s largest manufacturers of power supplies. His 33-year experience includes the analysis, simulation, and design of high-frequency, high-power-density, single-phase and three-phase power processors; modeling, simulation, evaluation, and application of high-power semiconductor devices; and modeling, simulation, analysis, and design of analog and digital electronics circuits. He has published over 80 technical papers and holds five U.S. patents. Dr. Huber is the recipient of the IEEE Power Electronics Society (PELS) Transactions Prize Paper Award for the best paper published in 2009 and of the Yugoslav Conference on Electronics, Telecommunication, Automation, and Nuclear Technique (ETAN) Best Paper Award in 1990.
Articles written by Laszlo Huber in How2Power Today:
Single-Stage Flyback LED Driver Meets Class C Limits on Harmonic Currents
Charles Hymowitz
Charles Hymowitz is a technologist, marketer and business executive with over 25 years of experience in the engineering services and EDA software markets. Mr. Hymowitz has been Chairman and CEO of AEi Systems, LLC since its re-organization in 2002. He currently guides all aspects of the company’s operations including technical services, product quality, sales and a staff of over 30 in-house and consulting engineers.
Articles written by Charles Hymowitz in How2Power Today:
Lost in Space: Unpredictable Aging Can Send Resistor Accuracy Way Off Course
Radu H. Iacob
Radu H. Iacob is a product design manager at ON Semiconductor, coordinating design and product engineering activities, from concept to market, on various products lines such as non-volatile memories, digital potentiometers and power management circuits. He has been with ON Semiconductor since 2008. Previously, he held the position of design manager at Catalyst Semiconductor, in charge of design and product introduction for EEPROM memories and other mixed-signal products. He was an employee of Catalyst Semiconductor since 1996. Prior to that, Iacob was a research engineer at the Institute of Micro-technology in Bucharest, Romania. Iacob has co-authored over 20 patents and scientific papers, and holds MS and PhD degrees from the Politehnica University of Bucharest.
David Jacquinod
David Jacquinod graduated with a Master’s degree in power electronics from the Ecole Centrale Marseille, France in 1996. He is currently an application and marketing manager in International Rectifier’s Automotive Business Unit where Jacquinod is in charge of defining and promoting the Intelligent Power Switch products and low-voltage ICs.
Articles written by David Jacquinod in How2Power Today:
Automotive Battery And Component Technologies Address Start-Stop Design Challenges
Matt Jenks
Matt Jenks graduated from Michigan State University with a BSEE. He worked ten years for Motorola at both their Automotive and Industrial Electronics Group and Semiconductor Products Sector, in hardware and sales engineering roles. His work included the maintenance and development of powertrain control modules and related custom ICs. He has also worked at Visteon as an electrical engineer and Vishay Intertechnology as a sales engineer. Matt has been with International Rectifier as an automotive field applications engineer for over 7 years.
Articles written by Matt Jenks in How2Power Today:
Livin’ On The Edge: Switching Converter Slew Rate Is Key To Mitigating EMI In Automotive Environments
Bill Johns
Bill Johns is an applications engineer for bqTESA Wireless Power at Texas Instruments where he specializes in power conversion for portable battery powered applications. Bill has 20 years of design experience in the field of power conversion across a number of different markets. He received his BSEE from University of Texas in Dallas. Bill can be reached at ti_billjohns[at]list.ti.com.
Articles written by Bill Johns in How2Power Today:
Milan M. Jovanović was born in Belgrade, Serbia. He received the Dipl. Ing. degree in Electrical Engineering from the University of Belgrade, Belgrade.
He is currently the Chief Technology Officer of the Power Systems Business Group of Delta Electronics, Inc., Taiwan, one of the world’s largest manufacturers of power supplies, and Vice President for R&D of Delta Products Corporation, Research Triangle Park, NC.
Girish R. Kamath
Girish R. Kamath graduated with a Masters degree in 1996 and a Ph. D in Electrical Engineering from the University of Minnesota in 1998. Since then Girish has been working in the U.S. motor drives and plasma cutting industries. He also has work experience in the Indian power electronics industry, in the area of high-frequency power conversion for UPS applications. Girish currently designs power electronic systems and controls for plasma-cutting power supplies. His main areas of interest are the multi-physics modeling approach to power component design, high-voltage circuits, and digital control.
Articles written by Girish R. Kamath in How2Power Today:
Simple Control Method Tames Flux Saturation In High-Frequency Transformer-Link Full-Bridge DC-DC Converters
Mike Kania
Mike Kania is currently the business development manager for Eltek, a provider of power electronics and energy conversion products. Mike has been with Eltek and Valere (a power supply company acquired by Eltek) for more than eight years. In this role, Mike’s focus has been on the introduction of state-of-the-art dc power systems technology into new applications and new market segments. Much of his work has been associated with the introduction of high-efficiency rectifier technology and the business cases that accompany its utilization. This has included the development of products designed for telecom applications such as switching centers, wireless cell sites, and broadband access systems. Most recently, Mike has focused on the introduction of switch-mode rectifier systems into traditional industrial markets such as power generation and distribution; railroads; oil and gas; water and wastewater; mining; and industrial processing.
Articles written by Mike Kania in How2Power Today:
Suresh Kariyadan joined International Rectifier in June 2009 as senior staff engineer for POL Applications, Enterprise Power Business Unit (EPBU) where he is responsible for all Point Of Load customer support for the EPBU. The role involves understanding the customer’s power supply requirements, providing reference designs, layout of PCBs, design verification tests, troubleshooting customer application boards and evaluating new product performance in application circuits.
Prior to joining International Rectifier, Suresh held senior engineering positions with Maxim Integrated Products and Cherokee International. He holds a Bachelor Degree in Electronics and Telecommunication from Kerala University, India.
Articles written by Suresh Kariyadan in How2Power Today:
Reverse-Current Phenomenon in Synchronous Rectifiers
Marian K. Kazimierczuk
Marian K. Kazimierczuk received the M.S., Ph.D., and D.Sci. degrees in electronics engineering from the Department of Electronics, Technical University of Warsaw, Warsaw, Poland, in 1971, 1978, and 1984, respectively. He is currently a professor of electrical engineering at Wright State University, Dayton, OH. His areas of research are in high-frequency high-efficiency RF power amplifiers, resonant and PWM dc-dc power converters, high-frequency rectifiers, modeling and control of converters, high-frequency magnetics, power semiconductor devices, electronic ballasts, RF transmitters, sensors, and superconductivity. He is a Fellow of IEEE and has published more than 230 papers
Articles written by Marian K. Kazimierczuk in How2Power Today:
An Overview and Simulation of DC-DC-AC and Z-Source Grid Connected Inverters
Sameer Kelkar
Sameer Kelkar joined Power Integrations in 2002 and is currently a senior applications engineer. He has a Masters degree in Electrical Engineering from the University of Minnesota.
Articles written by Sameer Kelkar in How2Power Today:
Software Speeds Transformer Design For AC-DC Power Supplies
Ramesh Khanna
Ramesh Khanna is a senior applications engineer with Texas Instruments’ High Reliability group where he is responsible for supporting customer design issues. Ramesh has more than 30 years of industry experience. He has a bachelor’s degree in engineering from Concordia University (Montreal, PQ, Canada) and a master’s degree in engineering from the University of Colorado (Boulder, CO). Ramesh can be reached at ti_rameshkhanna@list.ti.com.
Articles written by Ramesh Khanna in How2Power Today:
Tips For Applying POL Converters In Downhole A nd Other Harsh Environments
Paul Kierstead
Paul Kierstead has been in the semiconductor business since 1984. He has held engineering and marketing positions in the high-speed interface and interconnect sectors and most recently has been dedicated to power semiconductor devices. Paul has lead efforts in power market analysis, developed market and product strategies and has driven marketing business development efforts. Paul joined Cree SiC Power Products Group in 2008 as the director of marketing. In that role, he is responsible for Cree’s global SiC business development, applications support and new product strategy. Prior to joining Cree, Paul was employed by Fairchild and National Semiconductor.
Articles written by Paul Kierstead in How2Power Today:
Silicon Carbide Power Solutions Are Ready To Revolutionize Motor Drives
Jonathan Kimball
Dr. Jonathan Kimball received a BS from Carnegie Mellon in 1994 and an MS from the University of Illinois at Urbana-Champaign in 1996. He then worked in industry, first for Motorola (designing IGBT modules) and then for Baldor (designing industrial motor drives). Kimball returned to the University of Illinois as a research engineer in 2003. He subsequently co-founded SmartSpark Energy Systems (now named SolarBridge Technologies). After receiving a PhD from Illinois in 2007, he joined Missouri S&T as an assistant professor. Kimball’s research interests include photovoltaic systems, hydrokinetic energy, and digital control of power converter systems.
Isik C. Kizilyalli
Isik C. Kizilyalli is the CTO and founder of Avogy. Prior to founding Avogy, he held technical and management positions at Bell Laboratories (AT&T and Lucent Technologies), Agere Systems, Nitronex, and Alta Devices. His research, development, and commercialization experience covers a broad range of semiconductor materials (Si, GaAs, InP, and GaN), devices, and technologies (CMOS, BiCMOS, HFETs, detectors, HBT, photovoltaics). Kizilyalli is a fellow of the IEEE and was the recipient of the Distinguished Member of Technical Staff award by Bell Laboratories. He received a B.S. and Ph.D. degree in Electrical Engineering from the University of Illinois at Urbana. Kizilyalli has published 100 technical papers and has 45 U.S. patents.
Philip T. Krein
Philip T. Krein received the B.S. degree in electrical engineering and the A.B. degree in economics and business from Lafayette College, Easton, Pennsylvania, and the M.S. and Ph.D. degrees in electrical engineering from the University of Illinois, Urbana. He was an engineer with Tektronix in Beaverton, Oregon, then returned to the University of Illinois. At present he holds the Grainger Endowed Director’s Chair in Electric
Machinery and Electromechanics as director of the Grainger Center for Electric Machinery and Electromechanics. His research interests address all aspects of power electronics, machines, and drives, with emphasis on nonlinear control approaches. He published an undergraduate textbook, Elements of Power Electronics (Oxford University Press, 1998). In 2001, he helped initiate the International Future Energy Challenge, a major student competition involving fuel cell power conversion and energy efficiency for machines. He holds twelve U.S. and four European patents. Dr. Krein is a registered professional engineer in Illinois and in Oregon. He was a senior Fulbright Scholar at the University of Surrey in the United Kingdom in 1997-98, and was recognized as a University Scholar in 1999, the highest research award at the University of Illinois. In 2003 he received the IEEE William E. Newell Award in Power Electronics. From 2005 to 2007 he was a Distinguished Lecturer of the IEEE Power Electronics Society.
Articles written by Philip T. Krein in How2Power Today:
Comprehensive Flux Estimator Implementation Procedures For Advanced Control Of Inverter-Fed Induction Machines
Alain Laprade
Alain Laprade received an MEng in electrical engineering from McGill University in Montréal in 1984. Since then he has worked in power supply development for commercial, telecommunication, automotive, and aerospace applications as an applications engineer. In 2010, he relocated to Rhode Island to join ON Semiconductor’s Analog Power Group New Product Development team.
Articles written by Alain Laprade in How2Power Today:
Simplified Analysis Of A DCM Boost Converter Driving An LED String Part I: Theoretical Analysis
Bill Laumeister
Bill Laumeister is an engineer in strategic applications with the Precision Control Group at Maxim Integrated Products. He works with customers who use DACs, digital potentiometers, and voltage references. He has more than 30 years of experience and holds several patents.
Articles written by Bill Laumeister in How2Power Today:
Self-Starting Can Be Hard To Do–Understanding Power-On-Reset Requirements In Regulators And Bandgaps
Tom Lawson
Tom Lawson has been involved with instrumentation since 1968. During the 1970s he worked in medical electronics with Bill Morong, the principal inventor of predictive energy balancing. During the 1980s and 90s he built his own instrumentation company. Since rejoining with Bill Morong, the focus has been power conversion. Lawson started CogniPower in 2009 to begin the commercialization process. Lawson is named on eight issued patents and five patents pending, spanning four decades.
Articles written by Tom Lawson in How2Power Today:
Predictive Energy Balancing Enhances Control of Power Converters
Julie J. Lee
Julie J. Lee holds a BS and MS in electrical engineering from Wright State University. She is currently pursuing her PhD in Electrical Engineering from Wright State University, and working as a research assistant and a graduate teaching assistant in the Department of Electrical Engineering at WSU. Her research interests are in power electronics, PWM dc-dc converters, and power semiconductors. Ms. Lee is a member of Tau Beta Pi and an IEEE student member.
Articles written by Julie J. Lee in How2Power Today:
Effects of Load Changes On The Control-to-Output Transfer Function Of A Buck-Boost Converter In CCM
Leonard Leslie
Leonard G. Leslie, Jr. received the B.S. degree from Virginia Tech in 2001 and M.S. degree from the Center for Power Electronics Systems (CPES), Virginia Tech 2002. He is currently the manager of Space Product Engineering at VPT Inc. in Blacksburg, Va. Leonard has combined his experience in the Navy Nuclear Power Program and power electronics design to develop and validate custom and standard radiation-hardened dc-dc converter solutions to support the space industry.
Articles written by Leonard Leslie in How2Power Today:
Rad Hard Processors And Power Converters Propel Intermediate Bus Architecture Into Space Applications
Alex Lin
Alex Lin is an application engineer for Fairchild Semiconductor’s PCIA computing product line. He has been with Fairchild for about six years. Alex holds a B.S.E.E. and an M.S.E.E. degree from National Taiwan University of Science and Technology.
A More-Efficient Half-Bridge LLC Resonant Converter: Four Methods For Controlling The MOSFET
Greg Lubarsky
Greg Lubarsky is a senior applications engineer with National Semiconductor’s Grass Valley design center and works in the Mobile Devices Power group. He received his Bachelor of Science degree in Electrical Engineering from the University of California, Davis in 2002. Lubarsky has over seven years of experience as an applications engineer working with white LED backlight drivers, LED flash drivers and other power management electronics.
Articles written by Greg Lubarsky in How2Power Today:
Give Your Battery A Rest With A Supercapacitor-based Power Subsystem
Yanping Ma
Yanping Ma is currently the head of Quality and Reliability at Efficient Power Conversion (EPC). She received her Ph.D in Materials Science and Engineering from the University of California at Berkeley in 1996. Prior to joining EPC, she held various engineering positions in silicon component R&D at International Rectifier.
Articles written by Yanping Ma in How2Power Today:
Arindam Maitra is a senior project manager at the Electric Power Research Institute (EPRI). He is responsible for leading and managing activities related to the power system infrastructure requirements for plug-in hybrid vehicles. He is also conducting and managing numerous research activities associated with power systems and power electronics. Prior to joining the Electric Transportation group, Maitra worked as a senior project manager in the System Analysis and System Studies group, conducting and managing a wide range of research activities and power system studies in the transmission, distribution, power quality, and IntelliGrid research areas. Maitra holds two patents for the Intelligent Universal Transformer design topology and one patent in solid-state switchgear topology. Maitra received his B.E. degree from the Regional Engineering College, Nagpur, India, and holds an M.S. and a doctorate in electrical engineering from Mississippi State University. Maitra is also a recipient of the 2005 and 2010 Chauncey Award.
Articles written by Arindam Maitra in How2Power Today:
Utility Direct Technology Boosts Efficiency Of Fast Charging For Electric Vehicles
Amitabha Mallik
Amitabha Mallik received his Bachelor’s of Engineering from Visveswaraiah Technological University, Belgaum, India in 2008. He is pursuing his MTech at MIT, Manipal University, Manipal, India, in Power Electronics Systems and Control. He is currently working at Strategic Technology Group, Pune, India. His areas of interests are power semiconductor devices, motor drives and control, PWM dc-dc converters, and OrCAD/PSPICE (system-level simulations).
T. K. Man
T. K. Man received the BSc (Hon) degree at Manchester Polytechnic in 1984, MSc degree in engineering at Hong Kong Polytechnic University in 1999 and MSc degree in IC Design Engineering at Hong Kong Science and Technology University in 2007. Man has 22 years experience in power supply design, both linear and switching. He joined National Semiconductor in 2004 as a product application manager in Hong Kong. Prior to National, Man worked at Motorola and ON Semiconductor. His research interests include control modeling of SMPS, LED lighting systems and energy harvest technology. He is a senior member of IEEE.
John Mandelcorn
Josh Mandelcorn is a member of the Group Technical Staff at Texas Instruments where his focus is on low-power isolated and nonisolated converters. With more than 30 years of power supply/system experience, Josh has either invented or co-invented 17 U.S. patents. Josh received his BSEE from Carnegie-Mellon University, Pittsburgh, Pennsylvania. In 1998 he was appointed Distinguished Member of Technical Staff in Bell Labs. Josh can be reached at ti_joshmandelcorn[at]list.ti.com.
Vincenzo Marano
Vincenzo Marano is a system and application manager in the Industrial and Power Conversion Division, STMicroelectronics. He received a degree in electronic engineering from the Politecnico di Milano, Italy, in 2000 and then joined STMicroelectronics. His main focus is on motor drivers, MOS/IGBT drivers and industrial ICs. He is the author of papers and holds several patents on motor control ICs and architectures.
Articles written by Vincenzo Marano in How2Power Today:
System-On-Chip Architecture Raises Performance Of Microstepping Motor Driver Designs
Michelangelo Marchese
Michelangelo Marchese is a technical marketing engineer in the Industrial & Power Conversion Division of STMicroelectronics. He is based in Catania (Italy). Marchese joined the company in 1997 as a front-end engineer for smartpower devices, then became a marketing engineer for Intelligent Power Switches (IPS) for industrial. He is also experienced in software development for programmable logic controllers (PLCs).
Articles written by Michelangelo Marchese in How2Power Today:
Use Intelligent High-Side Power Switch To Satisfy Safety Requirements In Process Control And Industrial Automation
Jack Marcinkowski
Jack Marcinkowski holds the position of senior technical marketing and applications manager in International Rectifier’s Automotive Business Unit and is responsible for development of power modules with a focus on HEV and EV applications. Jack first joined IR in 2003 as an applications design manager working for the Automotive Business Unit for four years and re-joined IR in July of 2011. His professional experience includes many years of working as a marketing manager, engineering manager and power electronics design engineer in the area of industrial and automotive power electronics and in the semiconductor industry. Besides IR, Jack has worked for General Motors, Fairchild Semiconductor and National Semiconductor where he held multiple positions with increasing responsibilities. Jack holds an MSEE degree from Technical University in Warsaw, Poland as well as an MBA degree from UCLA in Los Angeles, California.
Articles written by Jack Marcinkowski in How2Power Today:
IGBT Devices And Modules Evolve To Address Inverter Design Challenges In Electric And Hybrid-Electric Vehicles
Colonel W. T. McLyman
A recognized authority in the field of magnetics design with 47 years of experience, Colonel McLyman is an accomplished inventor, author, and lecturer. He holds fourteen U.S. Patents on magnetics-related concepts and has written four popular textbooks including the recently revised and expanded, Third Edition of Transformer and Inductor Design Handbook.
McLyman retired as a senior member of the Avionics Equipment Section of the Jet Propulsion Laboratory (JPL). In his thirty years at JPL in power conversion and as the magnetics specialist, McLyman wrote over seventy JPL Technical Memorandums, New Technology Reports, and Tech-Briefs on the subject of magnetics and circuit designs for power conversion, fifty of which have been published by NASA. McLyman is President of Kg Magnetics, Inc., which specializes in power magnetics design.
Articles written by Colonel W. T. McLyman in How2Power Today:
Jean-Jacques Meneu is a technical marketing engineer in the Industrial & Power Conversion Division of STMicroelectronics. Since joining the company in 1997, he has focused on industrial applications. Meneu received a degree in Electronic Engineering from the National Superior Electronics School in Paris, France.
Articles written by Jean-Jacques Meneu in How2Power Today:
Non-Dissipative Control Saves Power And Cost In Stepper Motor Applications
Jean-Jacques Meneu
Jean-Jacques Meneu is a technical marketing engineer in the Industrial & Power Conversion Division of STMicroelectronics. Since joining the company in 1997, he has focused on industrial applications. Meneu received a degree in Electronic Engineering from the National Superior Electronics School in Paris, France.
Articles written by Jean-Jacques Meneu in How2Power Today:
Non-Dissipative Control Saves Power And Cost In Stepper Motor Applications
David Morrison
David G. Morrison, Editor/Publisher of How2Power.com, is a veteran technical writer and editor. Prior to founding How2Power.com, Morrison served as Editor-in-Chief of Power Electronics Technology (PET) magazine. Prior to joining Power Electronics Technology, Morrison served as a Technology Editor at Electronic Design magazine where he reported on analog & power technologies, and as an associate editor at Electronic Products magazine, where he reported on analog ICs and other components.
Before becoming an editor, Morrison worked for several years as an electrical engineer at audio and RF electronics companies. Morrison received a BSEE from the University of Rochester.
Hui Nie
Hui Nie is the director of device technology at Avogy. He has spent nearly 20 years working on semiconductor electronic and optoelectronic devices; including GaAs, InP and InAlAs-based avalanche photodiodes (APD), PIN photodiodes, laser diodes and solar cells. Before Avogy, Nie was the lead solar cell designer at Alta Devices, and world recorder holder of the most efficient single-junction solar cell. He has held positions as director of product line management, director of advanced technology and senior engineer at Source Photonics, Finisar, Triquint and Lucent Technologies. Due to his contributions, InP-based APDs transitioned from R&D lab into mass production, and are now widely deployed around world in fiber-to-the-home (FTTx) applications. Nie received a B.S. degree in Physics from University of Sciences and Technology in China in 1993, and a Ph.D. in Electrical Engineering from the University of Texas at Austin in 1998. He is a senior member of IEEE for his contributions toward telecommunication APDs, receivers and transceivers.
Vertical Devices In Bulk GaN Drive Diode Performance To Near - Theoretical L imits
Kim Nielson
Kim Nielson is a Sr. Engineering Technician for National Semiconductor's Design Center (Phoenix), where he has worked for five years. The center's products include next-generation PWM power controllers, gate drivers, and hot-swap and load-share controllers. Before joining National Semiconductor, Nielson spent 15 years as a power supply proto-type development specialist for commercial, military, and space applications. In his spare time, he enjoys golf, music, and travel.
Articles written by Kim Nielson in How2Power Today:
Increase Boost Regulator Efficiency With Synchronous Rectification
Rich Nowakowski
Rich Nowakowski is a product marketing manager for dc-dc converters within TI’s Power Management group. Rich received his BSEE and MBA from North Dakota State University, Fargo, ND.
Articles written by Rich Nowakowski in How2Power Today:
Techniques For Implementing A Positive And Negative Output Voltage For Industrial And Medical Equipment
Michael O'Loughlin
Michael O'Loughlin is an applications engineer with the Power Supply Control Products group at Texas Instruments. He specializes in offline and isolated power supply design and has authored numerous articles on power factor correction and power supply design related topics. Michael received his Bachelor of Science degree from the University of Massachusetts.
Minyoung Park
Minyoung Park is an application engineer at Fairchild Semiconductor, where he is an expert in power electronics. Park joined Fairchild in 2011, and is currently focused on induction heating applications in consumer power systems. He received his master’s degree in power electronics from Kyungpook National University in 2011.
Kevin Parmenter
Kevin Parmenter has over 20 years of experience in the electronics and semiconductor industry. Presently the director of Advanced Technical Marketing for Digital Power Products at Exar, Kevin previously led global product applications engineering and new product definition for Freescale Semiconductors AMPD - Analog, Mixed Signal and Power Division based in Tempe, AZ. Prior to this, he worked for Fairchild Semiconductor in the Americas as senior director of field applications engineering. In this role, Kevin led the FAE team in the Americas region plus three regional design centers.
Previously Kevin held various technical and management positions with increasing responsibility at ON Semiconductor and in the Motorola Semiconductor Products Sector. Kevin also led an applications engineering team for the start-up Primarion where he worked on high-speed electro-optical communications and digital power supply semiconductors.
Kevin is president and serves on the board of directors of the PSMA (Power Sources Manufacturers Association) and was the general chair of APEC 2009 (the IEEE Applied Power Electronics Conference.) Kevin has also had design engineering experience in the medical electronics and military electronics fields. He holds a BSEE and BS in Business Administration, is a member of the IEEE, and holds an Amateur Extra class FCC license (call sign KG5Q) as well as an FCC Commercial Radiotelephone License.
Articles written by Kevin Parmenter in How2Power Today:
Bad HR Processes Stymie Efforts To Hire Talented Engineers
Parviz Parto
Parviz Parto is director of Systems Applications Engineering at International Rectifier where he is responsible for defining and developing power management products for point-of-load (POL) applications. Parviz has more than 15 years of design experience in power electronics. He received his M.S. from Chalmers University of Technology, Gothenburg, Sweden in electrical engineering. Parviz is author or coauthor of many technical papers and holds U.S patents in the area of power management. His interests include high-frequency switched-mode power supplies and ICs for power management applications.
Articles written by Parviz Parto in How2Power Today:
Voltage-Mode Control Scheme Improves Buck Converter Performance At High Frequencies
Jeff Perry
Jeff Perry is the senior development manager for National Semiconductor's WEBENCH online design environment. He spent the first part of his career in semiconductor process engineering and the latter portion in power supply applications and development. He has been involved with the WEBENCH tool since it's inception in 1999. Jeff graduated from UCLA with a BS in physics and received an MBA from San Jose State University. He holds 10 patents.
Articles written by Jeff Perry in How2Power Today:
Enrico Poli is a senior application engineer for STMicroelectronics in Agrate Brianza, Italy. Since 2006 he has worked in the Industrial Business Unit, Motor Control Team, with a focus on monolithic solutions.
Articles written by Enrico Poli in How2Power Today:
System-On-Chip Architecture Raises Performance Of Microstepping Motor Driver Designs
Vlado B. Porobić
Vlado B. Porobić received the B.S., M.S and Ph.D. degrees in electrical engineering from the Faculty of Technical Sciences, University of Novi Sad, Serbia, in 2000, 2005, and 2011, respectively. From 2000 to 2011, Vlado was employed on the Faculty of Technical Sciences, as a teaching and research assistant in the Department for Power Electronics and Electrical Machines. Since 2011 he has been with Typhoon HIL in Novi Sad where he is working as a power electronics application engineer, developing various control applications for testing and evaluating HIL models and accompanying software. His main research is focused in the area of power electronics and motor control.
Roberto Prieto
Roberto Prieto was born in Madrid, Spain. He received the M.Sc. and Ph.D. degree in electronic engineering from the Technical University of Madrid, Spain, in 1993 and 1998 respectively. Since 1994, he has been an assistant professor at the Technical University of Madrid, where he is currently associate professor and deputy vice-president for research. He has published more than 100 papers in International conferences and journals, most of them from the IEEE. His research interests include high-frequency magnetic components, modeling of power electronics systems and development of CAD tools for power electronics applications.
Articles written by Roberto Prieto in How2Power Today:
Paul Pu joined Integrated Device Technology (Shanghai) Co., Ltd. in 2009 and serves as a marketing director at present. Paul brings almost ten years experience in the power and energy industry and holds M.S. and B.S. degrees in electrical engineering from Tsinghua University.
Energy Meter Design Operates Accurately Over Wide Current Range
Shishir Rai
Shishir Rai received his B.Tech. degree in electrical engineering from the Indian Institute of Technology, Madras, India in 2002 and his M.S. degree in electrical engineering from the University of Notre Dame, Notre Dame, Indiana in 2005 with a focus on the design of high speed III-V devices. He has been with International Rectifier since 2005 where he has worked in the areas of power device design, high-voltage IC design, applications engineering and technical marketing.
Articles written by Shishir Rai in How2Power Today:
MOSFET Package Technology Enhances Performance Of Motor Drives
Tom Ribarich
Since joining International Rectifier (IR) in 1996, Tom Ribarich has been the director of IR’s Lighting IC Design Center where he is responsible for developing control ICs for the global lighting market, including fluorescent, halogen, HID, LED and LCD backlighting applications. Prior to that, Tom was employed by Knobel Lighting Components in Switzerland where he designed dimmable electronic ballast systems for a variety of applications. Tom holds a BSEE degree from California State University, Northridge and a Master’s degree in ASIC design from University of Rapperswil, Switzerland.
Articles written by Tom Ribarich in How2Power Today:
Steve Sandler has over 30 years of experience in engineering. He is the founder and CTO of AEi Systems, LLC and is responsible for worst-case circuit analysis of power, RF, and linear systems as well as the design of AEi Systems’ line of rad-hard dc-dc converters. Mr. Sandler is president of SM Sandler Holdings, LLC and is a recognized author, educator and entrepreneur in the areas of power, RF and instrumentation
Articles written by Steve Sandler in How2Power Today:
Lost in Space: Unpredictable Aging Can Send Resistor Accuracy Way Off Course
Benjamin Sarpong
Benjamin Kwame Sarpong is a systems and applications engineer for TI’s Battery Management Group. He received his BSEE and MSEE from the University of Virginia. He also holds an MBA Degree from the McCombs School Of Business at the University of Texas, Austin. Ben has been at TI for 13 years and served in several roles during this time. He is a senior member of the TI Technical Staff. He previously held the position of engineering operations manager in the TI Storage Products Group. Ben is also a co-sponsor of the Texas Instruments—Africa Analog University Relations Program, where he is working with universities in Ghana to develop the mixed-signal design talent and in collaboration with Cadence has setup a Cadence Design Lab at the Kwame Nkrumah University of Science and Technology in Ghana.
Articles written by Benjamin Sarpong in How2Power Today:
A Guide To Selecting Battery Management Controllers When Designing Li-Ion UPS Systems
Paul L. Schimel
Paul Schimel spent his early years developing a wide ranging interest in all this electrical and mechanical, investigating and eventually repairing all types of equipment. He was working conventional machine tools and welding by 14. Through high school, he fixed most anything that was breakable including yard equipment, two-way radio gear, power tools, TVs, and stereos. He attended the School of Electrical Engineering at the University of Illinois at Urbana Champaign, specializing in power electronics where he earned a BSEE degree.
After this, he spent eight years in successful design engineering roles in consumer equipment including power supply design for projection and direct view televisions and telecommunications equipment including ring generators, battery rectifiers/eliminators, dc-dc converters, and UPSs—both switch-mode and ferroresonant. He then moved on to field applications engineering where he has spent the last six years on power management support and design work for Unitrode/TI, Fairchild and International Rectifier. He has assisted successful designs from mW to MVA and from prototype stages to finished end equipment. He moonlights in broadcasting, antique test equipment restoration, metal working, wood working, TIG welding, loudspeaker building, and amateur radio (K5NJP). He holds a commercial radio telephone license, a refrigeration license, and PE license. Mr Schimel holds several patents on magnetic structures for power electronics and novel circuitry.
Articles written by Paul L. Schimel in How2Power Today:
Mike Schnecker has a BS from Lehigh University and an MS from Georgia Tech, both in electrical engineering. He has 22 years of experience in the test and measurement industry in applications, sales and product development roles, and has specialized in signal-integrity applications including jitter using oscilloscopes and other instruments. Prior to joining Rohde & Schwarz, Schnecker held positions at LeCroy and Tektronix. While at LeCroy, he was responsible for the deployment of the SDA series of serial data analyzers. Schnecker currently serves as business development manager at Rohde & Schwarz.
Hiroo Sekiya
Hiroo Sekiya was born in Tokyo, Japan, on July 5, 1973. He received the B.E., M.E., and Ph. D. degrees in electrical engineering from Keio University, Yokohama, Japan, in 1996, 1998, and 2001 respectively. Since April 2001, he has been with Chiba University and now he is an assistant professor at Graduate School of Advanced Integration Science, Chiba University, Chiba, Japan. Since Feb. 2008 to Feb. 2010, he was with the Department of Electrical Engineering, Wright State University, Ohio, USA, as a visiting scholar. His research interests include high-frequency high-efficiency tuned power amplifiers, resonant dc-dc power converters, dc-ac inverters, and digital signal processing for wireless communication.
Articles written by Hiroo Sekiya in How2Power Today:
For the past year, Upal Sengupta has been Texas Instruments’ marketing manager for portable power. Prior to that, he worked as an applications and systems engineer in TI’s battery management and power conversion business units. Before coming to TI, Upal was a power system design engineer for mobile phone and portable computer OEMs, and a customer for both TI and National Semiconductor components. Upal has a BSEE from the University of Illinois and MSEE from Michigan State University.
Articles written by Upal Sengupta in How2Power Today:
Hemal Shah is the head of systems products at Avogy where Avogy's bulk GaN products are leveraged to make state-of-the-art power electronics systems. Prior to Avogy, Shah was the director, strategic marketing and applications at International Rectifier where he was responsible for new technology platform development, product strategy and tactical business development for a $400M product line. Shah has authored many IEEE publications and power electronics and technical magazine articles. He has an MSEE from RPI, Troy, NY and an MBA from IE business school, Madrid.
Articles written by Hemal Shah in How2Power Today:
Vertical Devices In Bulk GaN Drive Diode Performance To Near - Theoretical L imits
Cornel Stanescu
Cornel Stanescu graduated in 1984 with a Master’s degree from the Faculty of Electronics of the Politehnica University of Bucharest. In 1998, Stanecu obtained his PhD in Microelectronics. Between 1984 and 1996 he was with ICCE (Development Center for Electronic Components) being involved in analog design, mainly in bipolar technology, developing voltage regulators, precision operational amplifiers and thermal sensors. From 1996 to 1998 he was with SEMICONIX Design, as technical manager for analog ICs. Since 1998, he has been working with the Romanian Catalyst group (now part of ON Semiconductor) as a design manager or technical lead for digital potentiometers, LDOs and thermal sensors, all in CMOS technology. Since 1984, Stanecu has been a visiting lecturer at the Faculty of Electronics of “Politehnica” University of Bucharest, teaching, both in Romanian and English languages, Project and Seminary classes at Analog Integrated Circuits course. He is also the main author of five patents (one Romanian and four U.S.) and has more than 30 papers presented at the Romanian Annual Semiconductor Conference (CAS), many recognized with best-of-the-section awards. For the last 10 years, Stanecu has been a member of the Paper Review Board and chairman at the same conference. An IEEE member since 1994, he was also a reviewer for the IEEE Transaction on Circuits and Systems II: Express Briefs.
Articles written by Cornel Stanescu in How2Power Today:
Internal LDO Circuit Offers External Control Of Current Limiting
Johan Strydom
Johan Strydom is currently the head of Applications Engineering at EPC Corporation. He received his Ph.D from the Rand Afrikaans University, South Africa in 2001. From 1999 to 2002 he was working as a GRA and post-doctoral researcher at the Center for Power Electronics (CPES), Virginia Tech. Prior to joining EPC, he held various application engineering positions at International Rectifier Corporation (IRF) and more recently at Linear Technology Corporation (LLTC), working on a wide range of consumer and industrial applications including motor drives, class-D audio, hybrid power modules and dc-dc converters for VRM and POL.
Articles written by Johan Strydom in How2Power Today:
Joel Turchi holds an engineering degree from the ENSEEIHT school, which is part of the National Polytechnic Institute of Toulouse. With 20 years of power supply design experience at Motorola and ON Semiconductor, Joel is a regular contributor of application notes for ON Semiconductor as well as articles for trade magazines. He holds 12 issued U.S. patents pertinent to control techniques, whereas six others are pending. Joel has originated several new concepts in the power conversion arena through the introduction of PWM and PFC controllers. Among these circuits are notable devices such as the MC44608 controller for flyback converters with secondary reconfiguration, the NCP1653 CCM PFC controller and the NCP1631 interleaved PFC controller.
Articles written by Joel Turchi in How2Power Today:
Frequency-Foldback Technique Optimizes PFC Efficiency Over The Full Load Range
Paul Vrabel
Paul Vrabel has worked at Sandia National Laboratories for 25 years. Most of those years were designing test circuits, fixtures and testers for various components throughout the Labs. During the past seven years, he has
worked in the Magnetics Department designing, developing, and qualifying function, in-process and design testers. Paul is a member of the Product Realization Team (PRT). Sandia is a multi-program laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy’s National Nuclear Security Administration under contract DE-AC04-94AL85000.
Articles written by Paul Vrabel in How2Power Today:
Testing Military Grade Magnetics: Transformers, Inductors and Coils
Ed Walker
Ed Walker is president of Design/Analysis Consultants, Inc. (DACI), a consulting firm specializing in design validation, risk assessment, and optimization of electronics and electromechanical technologies. Walker is the author of The Design Analysis Handbook, A Practical Guide to Design Validation (Elsevier). He is also the creator of Design Master, a probability-based analysis software tool, which complements the handbook. You can follow Ed through the DACI Newsletter and the Engineering Thinking blog. Ed also writes edgy psychological fiction.
Use Worst-Case Analysis Tool To Efficiently Validate Your Designs
Gordon Wang
Gordon Wang is in product line marketing for Fairchild Semiconductor’s computing product segment. He has been with Fairchild for over seven years, and has experience in development and marketing positions in the power electronics industry.
Articles written by Gordon Wang in How2Power Today:
A More-Efficient Half-Bridge LLC Resonant Converter: Four Methods For Controlling The MOSFET
Dewight Warren
Dewight Warren is a product definer in the Mixed-Signal Business Unit at Maxim Integrated Products. He has a BSEE from the University of Florida and an MBA from the University of Texas at Dallas.
Articles written by Dewight Warren in How2Power Today:
Ed Wenzel is an applications engineer for STMicroelectronics in Schaumburg, Ill. He joined the company in June 1998 in the power lab for various power supply applications. He has more than 40 years experience in the power field with various topologies and semiconductors. Ed has a BSEE degree from Northeastern University in Boston. He has publications and app notes in the power supply area and for LED applications. Ed has been awarded two patents.
Adjustable Clamp Circuit Enables Use of Lower-Voltage MOSFET In High-Voltage Flybacks
Bob White
Bob White is currently chief engineer at Embedded Power Labs and is a consultant to EPC. He has over 30 years experience in power conversion and has held management and individual contributor roles in product development, applications and systems engineering, and power electronics technology development. Bob is the principal author of the PMBus specifications. He has a BSEE from MIT, an MSEE from Worcester Polytechnic Institute, and is a Fellow of the IEEE.
High Step-Down Ratio Buck Converters With eGaN Devices
Tim Wilkerson
Tim Wilkerson joined Analog Devices in 2001 as a senior field applications engineer located in San Jose, Calif. Prior to that Tim was with STMicroelectronics and Waferscale Integration in central applications. Previous work includes 20 years in design and development for several companies in the Midwest, most recently at Basler Electric working on protective relays for power systems. Tim received a BSEE from Purdue in 1976 and an MSE with Electrical option in 1997 from Southern Illinois University.
Articles written by Tim Wilkerson in How2Power Today:
Switching-Regulator Insights: Achieving Longer Battery Life in DSP Systems
LK Wong
L. K. Wong received his Ph.D. degree at the Hong Kong Polytechnic University in 1999. Wong joined National Semiconductor (now Texas Instruments) as a senior product application engineer in 2006, working in the area of power electronics including modeling, control, and dc-dc power converter design. Currently, he is focusing on high-efficiency, high-performance LED driver design for general illumination and backlight applications. He is a member of the IEEE.
Huixian Wu
Huixian Wu currently holds the position of reliability manager for Vishay Intertechnology. She is a member of IEEE and AEC, and is the author of over 30 papers. Ms. Wu holds a B.S. in material science and M.S. in semiconductor materials from Zhejiang University; an M.S. in reliability engineering from the University of Maryland, and a Ph.D. in electrical engineering from Lehigh University.
Articles written by Huixian Wu in How2Power Today:
Failure Analysis On Power MOSFETs With Copper Wire Bonds
Felix Yao
Felix Yao joined Integrated Device Technology (Shanghai) Co., Ltd. in 2010 and currently serves as a senior application engineer. Felix brings over 10 years application experience in consumer and industrial products and holds a B.S. degree in electrical engineering from Nanjing Southeast University.
Energy Meter Design Operates Accurately Over Wide Current Range
Jae-Eul Yeon
Jaeeul Yeon serves as a principal application engineer at Fairchild Semiconductor, where he has worked for over six years. A specialist in power electronics, Yeon is now in charge of HV discrete products in consumer power supply systems such as display power supplies, induction cooking inverters, health care systems, etc. Yeon received his Ph. D. degree in electric and electronics engineering from Hanyang University in 2006.
Articles written by Jae-Eul Yeon in How2Power Today:
IGBT With Intrinsic Body Diode Improves Performance Of Single-Ended-Resonant Inverters In Induction Heating Applications
Bob Zwicker
Bob Zwicker received a BSEE in 1974 from North Carolina State University and began designing switching power supplies in 1980. He has one patented invention for a method of secondary-side control of synchronous rectifiers. Bob became an applications engineer in 2002 and began doing semiconductor power applications with Analog Devices in 2005. He lives and works out of his home in Olympia, Wash.
Articles written by Bob Zwicker in How2Power Today:
More Boost With Less Stress: The SEPIC-Multiplied Boost Converter
Sudharshana _
Sudharshana received his B.E degree in Electronics and Communication Engineering from Visvesvaraya Technological University, India in 2009 and his MTech from MIT, Manipal University, Manipal, India, in Power Electronics Systems and Control. He is currently working as a software engineer at Strategic Technology Group, Pune, India. His areas of interests are modeling and control of resonant and PWM dc-dc converters, embedded system design and development of motor drives hardware and firmware.
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