1. APEC Celebrates Its 35th Anniversary – See You in New Orleans March 15-19, 2020
   
2. You are Invited to Attend the PSMA Annual Meeting at APEC 2020
   
3. Meet Your Directors
   
4. About Our Members
   
5. Welcome to PSMA
   
6. Power Magnetics @ High Frequency: PSMA Magnetics Committee and IEEE PELS Pre-APEC Workshop
   
7. PSMA and IEEE PELS Sponsor Pre-APEC Workshop on Capacitors in Power Electronics
   
8. Registration is Open for EnerHarv 2020
   
9. 3D-PEIM 2020: The Third International Symposium on 3D Power Electronics Integration and Manufacturing
   
10. 2020 International Power Supply-on-Chip (PwrSoC) Workshop
    
11. WiPDA 2020 Workshop: The 8th Workshop on Wide Bandgap Power Devices and Applications
    
12. RoHS 3 – The countdown is engaged!
    
13. X Capacitor Discharge Must Satisfy Both Safety and Energy Efficiency Rules
    
14. Events of Interest – Mark Your Calendar

If you or anyone in your company is interested in getting on the distribution list for future issues of PSMA UPDATE, please send e-mail to: power@psma.com. Be sure to include your name and the name of your company.

Previous issues of update: Q2_2019 | Q3_2019 | Q4_2019

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PSMA UPDATE is published and distributed via e-mail quarterly by the Power Sources Manufacturers Association. Send editorial information and comments to:

Permission to reprint information and articles as published is granted: a courtesy line is appreciated.

Membership in PSMA is open to any organization or corporation involved in the power sources and supplies industry. For membership information, visit our website or contact us by fax, telephone or email.

If you or anyone in your company is interested in getting on the distribution list for future issues of PSMA UPDATE, please send e-mail to: power@psma.com. Be sure to include your name and the name of your company.

 

or thirty-five years, APEC has established itself as the leading power electronics conference and exposition and has evolved to be the annual get-together event for applied power electronics professionals for knowledge exchange and networking. APEC 2020 will be held at the New Orleans Ernest N. Morial Convention Center, New Orleans, LA, March 15 - 19, 2020 and, like its predecessors, APEC 2020 will once again offer attendees an extraordinary program of seminars, technical and industry sessions, forums and social events.

APEC 2020 is still scheduled to be held as scheduled from March 15-19, 2020 in New Orleans. We encourage you to review the conference's Travel Information page for tips and travel recommendations.

The APEC 2020 Conference Committee has put together:

• The Plenary Session on Monday, March 16 that will feature world-class presentations to keynote our week-long conference. And, if you can't make to the Monday plenaries in person, you can watch them on streaming video, courtesy of IEEE.tv.
• Eighteen Professional Development Seminars on Sunday, March 15 and Monday, March 16, presented by world-class experts designed to bring you up to speed on critical power electronics design technologies and techniques.
• 40 Presentation Sessions from Tuesday March 17 through Thursday March 19 plus a Dialog (Poster) event during the Thursday hosted lunch.  There will be over  600 high-quality, peer-reviewed papers  presented.
• 23 Industry Sessions running concurrently with the Technical Program will cover the latest developments presented by  the industry's leading innovators.
• Three controversial topics will be covered in the annual Rap Sessions held on Tuesday, right after the exhibits close at 5:00 p.m. Grab a cool beverage and bring your questions for the panelists.
• A busy exhibit hall packed with the latest power electronics products.
• The annual MicroMouse contest pitting teams from around the world to solve the maze the fastest with their intelligent motorized mice.
• A terrific social event that brings us all together at Mardi Gras World on Wednesday evening.

On the Saturday prior to the start of APEC2020, PSMA and PELS will again be sponsoring two workshops: the fifth High Frequency Magnetics Workshop "Power Magnetics @ High Frequency" and the third Capacitor Workshop "How to Choose and Define Capacitor Usage for Emerging Applications". For more information see the articles on each workshop in this issue of the UPDATE.

Speaking for all of us on the APEC Conference Committee, I invite you to come to New Orleans to be part of our annual gathering. You really don't want to miss it.  As the folks in New Orleans like to say, "Laissez le bon temps rouler." Check the APEC website for details (www.apec-conf.org).

Provided by Greg Evans, APEC 2020 Publicity Chair

he 2020 PSMA Annual Meeting will be held in conjunction with APEC 2020 at the New Orleans Ernest N. Morial Convention Center in New Orleans, LA on Monday March 16. A buffet breakfast at 7:30 a.m. will precede the meeting and individuals from member companies as well non-member guests are invited to attend and participate in a full agenda of topics of interest to the industry. At the meeting, you will have the opportunity to meet and interact with many of the students who received APEC Travel Support to present their papers at the Technical Sessions. year. Regular member company representatives will participate in the election of four Directors to serve on the PSMA Board for a three-year term beginning immediately and ending at APEC 2022. The detailed agenda for the meeting will be on the PSMA web site and will include reports from each of the technical committees and stimulating discussions on new PSMA initiatives for 2020 and beyond. The APEC 2020 Conference Chair will review the progress on APEC2020 and there will be a report on plans for APEC 2021 in Phoenix, AZ. There will also be invited presentations from iNEMI and IEEE PELS to review their activities and opportunities to continue to strengthen the relationships between PSMA and each of these organizations.

Members and guests are also invited to remain for the Board of Directors meeting that will immediately follow the Annual Meeting. Participation in these meetings will provide you with the opportunity to network with colleagues from other companies and to influence the direction of the PSMA and the power sources industry.

Another way to get more out of your company membership in PSMA is to get involved with one of our active technical committees. The Capacitor, Energy Harvesting, Energy Management, Industry-Education, Magnetics, Marketing, Power Electronics Packaging, Power Technology Roadmap, Reliability, Safety & Compliance, Semiconductor and Transportation Power Electronics committees all plan to hold open meetings during the week of APEC 2020. All are invited to participate or to just drop in any of these committee meetings to hear and provide input as the committee activities are being planned for the coming year. Visit the PSMA website to see the schedule of PSMA meetings and events at APEC 2020.

On March 14, 2020, the Saturday prior to the start of APEC 2020, PSMA and PELS will be sponsoring two workshops, the fifth High Frequency Magnetics Workshop -"Power Magnetics @ High Frequency" and the third Capacitor Workshop – " How to Choose and Define Capacitor Usage for Emerging Applications". Information on these workshops are available in separate articles in this issue of the Update.

Be sure to visit us at the PSMA booth, in the APEC hub #1325, in the exhibition area during APEC. PSMA is again sponsoring the popular PSMA/ APEC Passport Program in the Exhibit Hall. Visit the booths of participating PSMA members to enter your name into a raffle drawing.

We look forward to a good turnout at the PSMA meetings and a very busy and exciting week.

For the latest information on all of the activities planned during APEC 2020, visit us at www.psma.com.

our members of the Board of Directors are elected at the PSMA Annual Meeting held every year during the APEC conference. Each Director serves a three-year term and is eligible to be reelected for one additional term.

In this issue we would like to introduce you to Alexander Gerfer and Tim McDonald who are both serving their first term.

Alexander Gerfer Managing Director and Chief Technology Officer of Würth Elektronik eiSos group, one of Europe's largest manufacturers of electronic and electromechanical components with around 8,000 employees. The company is based in Waldenburg, Munich, Berlin and Barcelona, and has R&D locations in Silicon Valley, Dallas and Shenzhen.

The graduate electrical engineer learned his business from scratch as a radio and television technician. He completed his studies at the Rheinische Fachhochschule Köln. He is also the author of many technical articles and publications in the field of electronics design, author of the book "trilogy of inductors", co-author of various other textbooks and holds numerous patents.

At Wurth Elektronik eiSos, he is a man of the first hour and founded the product development as well as the quality management. His passion is to communicate electronic content to users of electronic components in an understandable way, without unnecessary ballast. Numerous Magnetics product designs and innovations are based on his constant research for more efficient components.

Today the Rhinelander is responsible for the product strategy of Wurth Elektronik eiSos and thus for the areas of product management, quality management, supply chain management, research and development. Alexander Gerfer also travels internationally as a sought-after key note speaker, lecturer and as a promoter and supporter of innovative hardware startups.

Provided by Alexander Gerfer, Managing Director and Chief Technology Officer,
Würth Elektronik eiSos GmbH & Co. KG
 

Provided by Tim McDonald, Senior Consulting Advisor
for the CoolGaNTM Program, Infineon Technologies
 

ULS was founded 40 years ago in Munich, Germany with a handful of engineers and one common goal; to revolutionize power supply technology.  Today, PULS is the leading manufacturer of the most efficient DIN-Rail switched mode power supplies and DC power products.  This was made possible by our focus and a global team that strives for the next stage of innovation for every PULS product.  Users can experience this ambition in the highest efficiency levels, longest service lifetimes, smallest form factors, and absolute reliability of all PULS products.

PULS is committed to developing and producing leading edge technologies and energy efficiency is at the heart of all PULS product designs.  Achieving the highest efficiency ratings possible reduces exess heat generation, minimizes power losses, and extends the service lifetimes of PULS products to provide users with the lowest total cost of ownership.  Minimizing excess heat generation also extends the lifetimes of surrounding components located near PULS power supplies.  The wide breadth of the PULS product offering enables users to select the best PULS products for their individual application requirements.  PULS products are frequently used in Proccess Automation, Material Handling, Food & Beverage, Semi-Conductor, Railway, Renewable Energy, Water & Waste Water, Automotive, and Building Automation applications throughout the world.

Production of all PULS products is carried out in two innovative and highly automated manufacturing plants in the Czech Republic and China. The entire value chain is kept under our full control, and this level of control is important to us. In customer audits, our plants are repeatedly praised for their efficiency, streamlined structure and environmentally friendly objectives.  Owning and operating multiple manufacturing facilities provides PULS the flexibility to ensure seamless delivery for a global market.

Innovative and efficient product designs are just a part of the PULS advantage.  PULS provides technical and commercal support globally to support customers needs and requirements.  PULS locations throughout the world maintain significant levels of inventory to ensure immediate availability and timely delivery for our customers.  Training session are provided regularly to better educate the market on the many critical aspects of PULS' industry leading products.  Detailed product specifications, application notes, drawings, agency approvals, and other valuable information can be found at www.pulspower.us

The next time you fly, recognize that it is -40 degrees outside, you are traveling at 500 miles per hour, 6 miles high, and there is not enough oxygen to survive. There are several hundred systems keeping you alive, comfortable, entertained, and flying in this environment. Astronics is the expert providing the power to those systems.

"At Astronics, innovation is in our core," explained Mark Peabody, President of Astronics AES. "We pioneered the in-seat power that passengers use while seated on a plane, and today there are more than a million seats outfitted with our product. Every day, our team members work side-by-side with customers to create exciting new technologies that, like in-seat power, will help transform the future of the flight experience."

To date, Astronics power engineers have generated dozens of patents for power systems on aircraft.

Astronics EMPOWER® in-seat power systems keep passengers powered throughout a flight.

Astronics now offers wireless charging for embedding in furniture and seat backs to charge the newest phones.

Driving Innovation in Aircraft Passenger and Crew Power Systems
Since launching in-seat power, Astronics has continued to innovate and expand its product line over the years. Today, major OEMS and airlines count on Astronics to provide the industry's most comprehensive, most certified, most widely deployed set of in-seat power solutions in the world.

"Recently we introduced USB Type-C outlets to serve laptops, phones, and other emerging devices powered by this new standard," Peabody said. "And what we're really excited about right now is wireless charging, where we're now able to provide inductive charging for the newest passenger devices. Creating this for the aircraft was a challenge where we had to satisfy stringent power and safety requirements, and today we're thrilled to say many first and business class seat manufacturers are implementing this new technology to service their most tech-savvy passengers."

Astronics in-seat power systems offer real-world impact on passengers and flight crews, enabling them to enjoy inflight entertainment and stay connected to loved ones throughout their journey without worrying about conserving device batteries.

Astronics is helping to drive the development of tomorrow's more electric aircraft.

On a Mission: To Drive the More Electric Aircraft
Astronics is also deeply involved with the industry drive to the more electric aircraft. From R&D efforts to thought leadership on emerging standards and solving technical issues, Astronics is creating products and systems for tomorrow's innovative aircraft. Astronics is supporting its longtime customers in new initiatives to bring more electrical systems to fixed-wing aircraft, rotorcraft, and now, the emerging class of electrical vertical take-off and landing (eVTOL) aircraft.

"We're thinking about the performance improvements that can be expected in transitioning to an aircraft where more systems are powered and monitored electronically. With our power systems, we're also incorporating smart sensing elements to help with vehicle health management and predictive maintenance. We're pushing power to do more than simply provide power -- we're excited to be introducing a whole new class of intelligent power systems for the evolved aircraft of tomorrow," Peabody said.

For airframe power, Astronics manufactures power generation, power conversion, and power distribution products. Incorporating the latest solid-state technologies and designs, these systems deliver highly efficient, clean electrical power that improves aircraft operation through weight and system wiring savings.

Astronics' starter generator units form the foundation of a more electric airframe power system.

The Importance of Culture at Astronics AES
Astronics AES considers culture to be at the heart of everything they do – from how they work together to how they serve their customers and their community. The culture tenets include learning, teamwork, humility, life, and at the center of it all, passion. "We believe it is the journey that is impactful – it provides us with opportunities to ask questions, learn from our challenges, and positively affect the lives of many people," Peabody explained.

Astronics employees show their Seattle Seahawks team spirit.

Located in beautiful Kirkland, WA, Astronics AES draws inspiration from a tech-focused community rooted in aerospace but that now incorporates the fast-forward pace of companies including Amazon, Google, and Apple who also call the Seattle area home.
Astronics AES is a wholly owned subsidiary of Astronics Corporation, which serves the world's aerospace, defense, and other mission-critical industries with proven, innovative technology solutions. Astronics experts work side-by-side with customers, integrating an array of power, connectivity, lighting, structures, interiors, and test technologies to solve complex challenges. For over 50 years, Astronics has delivered creative, customer-centric solutions with exceptional responsiveness. Today, global airframe manufacturers, airlines, military branches, completion centers, and Fortune 500 companies rely on the collaborative spirt and innovation of Astronics. Learn more at Astronics.com.

Provided by Ellen Cheng, Marketing Communication Coordinator, Astronics

Editors Note: We would like to feature your company in a future issue of the Update. Please contact the Association Office for information about how to submit an article for consideration.

Exxelia USA
James Tabbi
1221 N US Hwy 17-92
Longwood, FL 32750
Telephone: 585-729-7909
Fax: 585-243-383
E-mail: jtabbi@exxelia.com
Website: https://exxelia.com/us/

Exxelia is a manufacturer of complex passive components and precision subsystems focusing on highly demanding end-markets, applications and functions. Their product portfolio includes wide ranges of capacitors, filters, position sensors, slip rings, wound magnetic components and high-precision mechanical parts. Products are commonly used for power electronics, power generation, energy storage, and signal filtering functions in numerous leading industrial areas such as aviation, defense, space, medical, railway, oil & gas and telecommunications.

Exxelia is valued for its ability to meet complex specifications and develop standard and custom products complying with the most demanding qualification procedures intended to critical functions.

Megmeet USA, Inc.
Chavonne Yee
4020 Moorpark Ave Ste 115
San Jose, CA 95117-1846
Telephone: 408-893-4212
E-mail: chavonne.yee@megmeetusa.com
Website: http://megmeetusa.com/

Established in 2003, Megmeet USA is a high-tech company that focuses on power electronics and industrial control technology and is engaged in the R&D, production, sales and services of hardware, software and system solutions in the field of electrical automation. Their state-of-the-art technical platforms combine power electronics and control technology to provide everything from core components to complete solutions. Megmeet is a global pioneer of reliable, efficient power products for the consumer, industrial, and medical markets.

Phononics
Shye Shapira
HaTa'asiya 51
Nesher
Israel
Telephone: +972528747162
E-mail: shye@phononicstech.com
Website: https://phononicstech.com/

Phononics technology enables higher energy density drivers through advanced heat management solutions. Phononics applications include Transportation, Communication, Lighting and Renewable Energy. In Transportation, enabling the next generation of active sensors and RADARs that transmit in real time the vehicle location and its interaction with the surroundings. For Communication, the heat management of end-user devices will reduce heating and improve reliability. For Lighting, Phononics can remove the heating barrier of LED and LASER lighting and significantly increase light source efficiency and reliability. With Renewable Energy, Phononics-based energy converters will save significant energy losses and increase efficiency.

Premier Magnetics
Dennis Earley
20381 Barents Sea Circle
Lake Forest, CA 92675
Telephone: 949-452-0511
E-mail: dennis_e@premiermag.com
Website: premiermag.com

Premier Magnetics, incorporated in 1991, has become a recognized world leader as a multinational company producing and marketing a broad range of magnetics components. Premier has been providing quality products to the Communication, Computer, Industrial, and Medical industries, as well as various government and military agencies around the world. We are world class designers and manufactures of transformers and magnetics for Communication, Networking, and Power Applications.

Dedicated to delivering the highest quality products and short cycle times at the most competitive cost in the industry, Premier has sales and distribution locations throughout the world, with manufacturing locations in Southern California and China.

Teodora Plamenova Todorova
Technical University of Sofia
Department of Power Electronics
Block 1, Office 1402, 8 St. Kl. Ohridski
Sofia 1756 Bulgaria
Telephone: +359897900681
E-mail: t.todorova@tu-sofia.bg

 

Teodora Plamenova Todorova received the B.S. and M.S. degrees in communication engineering and technologies and the Ph.D. degree in electronics from Technical University of Varna, Varna, Bulgaria, in 2012, 2014 and 2018, respectively. As a part of her Ph.D. study, from 2016 to 2017, she was an Exchange Student at the Electrical Energy Laboratory, Ghent University, Ghent, Belgium, where she was conducting research in the area of high frequency power magnetic components and electrical conductivity of Mn-Zn ferrites.

Since 2019, she has been an assistant professor in the Department of Power Electronics at Technical University of Sofia, Sofia, Bulgaria. Her current research interests include high-frequency power magnetic components with focus on electrical properties of Mn-Zn ferrites and their influence on the core loss, total power loss in magnetic cores and a description of its nature, electronic circuits, equipment and approaches appropriate for measurements of magnetic core loss and characterization of the electromagnetic properties of soft-magnetic materials.

Prior to APEC 2020
Date: Saturday March 14, 2020
Ernest N. Morial Convention Center
New Orleans, LA

he PSMA Magnetics Committee together with IEEE PELS will hold the fifth "Power Magnetics @ High Frequency" workshop on Saturday, March 14, 2020 -  the day before and in the same venue as APEC 2020 at the Ernest M. Morial Convention Center, New Orleans, Louisiana.

The target audience for this workshop is all who wish to achieve higher power densities, low profile aspect ratio, higher efficiencies, and improved thermal performance.  The workshop content is especially suitable for:

DESIGNERS of power magnetic components
MANUFACTURERS of magnetic materials and magnetic structures
FABRICATORS of magnetic components
PROVIDERS of modelling and simulation software
MANUFACTURERS of test and characterization equipment

Workshop attendees are invited to arrive to the meeting room between 7:00 and 8:00 AM for a buffet breakfast and informal discussions with their colleagues and peers. There will also be an opportunity to preview the technology demonstrations during the breakfast session.

The workshop will consist of morning (modelling and characterization) and afternoon (winding techniques) technical sessions and a lunchtime interactive technology demonstration session. The two technical lecture presentation sessions will each be followed by a panel Q&A. The technology demonstrations will also be available during the breakfast prior to the opening session, during lunch and during the networking session at the end of the day's events.

The morning technical session will feature a keynote presentation and four lecture style presentations concluding with two panel Q&A sessions. There will be a five-minute Q&A after each lecture presentation. The tentative schedule for this session is:

• Tom Wilson, Simplis Technologies will present a keynote presentation "Benefits of Concurrent Design of Electric and Magnetic Circuits in Power Electronics"
• Pedro Alou and Alberto Delgado, University Polytechnic Madrid, will present "Modeling Approach of Magnetic Components Based on Equivalent Conductor Layer for Fast 3D Finite Element Simulations"
• Tom Wilson, Pedro Alou and Alberto Delgado will lead a panel discussion on modelling magnetic components. Everyone's participation is encouraged.
• Michael McHenry, Carnegie Melon, will present "Driving Motors to Higher Frequencies"
• Phyo Aung Kyaw, Resonant Link will present "Deriving Loss Models From Measurements"
• Mike Wens, MindCet, will present "Triangular Flux Excitation: The Proposed Standard for Measuring Power Inductors"
• Tom Wilson, Pedro Alou, Alberto Delgado, Michael McHenry, Phyo Aung Kyaw and Mike Wens will lead a panel discussion regarding issues associated with modelling magnetic components. Everyone's participation is encouraged.

The second session "Technology Demonstrations" will be coincident with the luncheon period. This will include an interactive session of technology demonstrations and/or presentations each addressing specific technical disciplines and capabilities consistent with the workshop agenda. The individual technology demonstrations will repeat as required with a five to ten-minute presentation and a five to minute Q&A during each small group interaction. Workshop attendees are encouraged to move between the technology demonstrations on approximately fifteen-minute intervals so they can cover as many of the demonstrations as possible during the session as well as to allow reasonably small groups for each technology demonstration.

The technical capabilities and disciplines that will be demonstrated and displayed during the technology demonstration session are as follows:

• Rodney Rodgers, Allstar Magnetics: Waves in Magnetic Cores
• Jose Molina, Frenetics: Real Time Magnetics Design Using Artificial Intelligence
• Tom Wilson, Simplis Technologies: Software Module for Design of Magnetic Components
• JC Sun, Bs&T:  Pulse Characterization of Magnetic Components
• Tobias Schuster, Omicron/Pico Test: DC Biased Impedance Measurements in Power Electronics Using a LF-VNA
• Chris Oliver, Micrometals:  Latest Advances in Inductor Design Software
• Thomas Brander, Wurth Elektronik: Thermal Behavior of Power Inductors at High Frequency
• Thomas Brander, Wurth Elektronik: Impact of Winding Configuration on Leakage Inductance and Circuit Performance
• Marcin Kacki, SMA Magnetics: Measurements to Demonstrate Dimensional Effects of Ferrites
• Chuck Wild, Dexter Magnetics:  Emerging Magnetic Materials and Magnetic Structures. 
• Ferroxcube: Joel Salas
• Hitachi: Mark Rine
• Magnetics: Brad Van Fleet
• Rubadue Wire: Kyle Jensen

Attendees will also be able to visit the technical demonstrations for the Capacitor Workshop "How to Choose and Define Capacitor Usage for Emerging Applications" that will be held concurrently.

There will also be four posters presented during the technology demonstration session

• Apoorv Agarwal, NCSU: Analytical comparison of Single Active Bridge and Phase Shifted Full Bridge PWM topologies
• Murat Kaymak, RWTH Aachen University: Winding and Magnetic Core Selection for Medium-Frequency Transformers
• Phyo Aung Kyaw, Aaron Stein, Charles Sullivan, Resonant Link: Groundbreaking Wireless Charging Performance for Every Application
• Rachel Yang, MIT:  Application Flexibility of a Low-Loss High-Frequency Inductor Structure

The third technical session will feature a keynote presentation and three lecture style presentations concluding with a panel Q&A session. Each presenter will speak for thirty minutes followed by a five-minute Q&A. The tentative schedule for this session is as follows:

• Charles Sullivan, Dartmouth will present a keynote overview covering "Survey of Winding techniques Used For Power magnetic Components"
• Minjie Chen, Princeton, will present "Modeling and Design of Multiwinding Planar Magnetics for High Performance Power Electronics"
• Kyle Jensen, Rubadue Wire, will present Technical Performance and Manufacturing Cost Trade-offs Between Litz Wire and Stranded Wire"
• Jannik Schaefer, ETH Zurich, will present "Design of PCB Winding Inductors Employing the CFFC-Compensating Fringing Field Concept"
• Panel Discussion: Charles Sullivan, Minjie Chen, Kyle Jensen and Jannik Schafer will address topics of interest relative winding techniques from the workshop attendees.  Everyone's participation is encouraged.

The workshop will close with remarks regarding the best of the best by Alexander Gerfer of Wurth Elecktronik summarizing the workshop presentations.

Following the closing remarks will be a networking hour with hors d'oeuvres, soft drinks, wine and beer from 5:00 to 6:00. This will provide an additional opportunity to visit the technology demonstration stations.

After February 1, the registration fee is $400 reduced to $300 for PSMA Members, PELS Members and students. Continuing Education Units (CEU) are available are available for participating in the workshop for a $5 fee. There will be a $25 surcharge for onsite registration, if available. Breakfast, lunch and the reception will be provided as part of the workshop. Electronic copies of all presentations will be made available to the workshop participants via a password protected website.

The latest information on agenda as well as registration information for the workshop will continue to be available on the PSMA website at: http://www.psma.com/technical-forums/magnetics/workshop.

Organizing Committee

Steve Carlsen, Raytheon Systems Company
Ed Herbert, PSMA
Rodney Rogers, Allstar Magnetics
George Slama, Wurth Elektronik
Fred Weber, Future Technology Worldwide
Chuck Wild, Dexter Magnetic Technologies Inc.
Matt Wilkowski, EnaChip

How to Choose and Define Capacitor Usage for Emerging Applications
- With a Focus on Wideband Trends and New Technologies -

he PSMA Capacitor Technical Committee and IEEE PELS are jointly sponsoring an all-day workshop titled "How to Choose and Define Capacitor Usage for Emerging Applications - With a Focus on Wideband Trends and New Technologies" on Saturday, March 14, 2020, the day before the start of and in the same venue as APEC 2020 at the Ernest N. Morial Convention Center in New Orleans, LA.

The time is getting closer and the attendee list is growing. This workshop is just around the corner with only a few weeks to go. Industry professionals from leading capacitor manufacturers and scientists from around the world will get together to address the latest challenges and developments on the technology and applications of capacitors. The mixture of technology-based presentations from industry, contributions from university professors, panel sessions with specialists and Q&A formats will make the day a high-class value for participants. In the morning over breakfast, during lunch, and at the final networking session attendees will have the chance to meet other workshop participants from around the world to have in-depth discussions on power electronics, capacitors and magnetics while exploring the vast array of demonstrations and posters from both this workshop and the 5th Power Magnetics @ High Frequency Workshop which will be held concurrently.

The 2020 capacitor workshop is the third of its kind, with the inaugural workshop in 2018, and has become an anticipated annual pre-APEC event. With the growing interest and excellent feedback from former attendees, we know that we deliver valuable insights and have identified topics for this year's agenda. The 2020 capacitor workshop will provide interesting and trending topics on the technologies and applications of capacitors in power electronics. The workshop will include an incredible mixture of professionals from market leading capacitor manufacturers such as KEMET, CDE & Wurth Electronics and international high-class lecturers from universities around the world.

This year's workshop will open with a keynote presentation on the challenges and requirements for capacitors in the electrification of future mobility. Additionally, this year's workshop will provide for selected students to present their Capacitor research in a poster session format.

In 2020 we will again feature the very successful and highly appreciated technology demonstration stations. These demonstrations will be available during the breakfast prior to the opening session, during the luncheon and during the closing networking session at the end of the day's events. This will provide attendees the opportunity to interact with the presenters one-on-one and to discuss the various technologies and their advantages for your needs. The demonstrations will include some of the world's leading measurement equipment manufacturers who will provide close-up opportunities to view the high accuracy of their latest developments.

The Capacitor workshop will address the specific needs of both novices and advanced designers of DC-DC converters, frequency drivers, inverters, and other power conversion applications. The workshop agenda covers application-based challenges rising from the use of GaN and SiC topologies on capacitor technologies, the impact of the rapidly emerging electrification of mobility products, as well as the latest capacitor developments. Finally, we will discuss the continuously growing demand for supercapacitors, applications for using ceramics in harsh environments, the application of capacitors at high frequencies and the latest advances in film capacitors.

The workshop will end at 5:00 p.m. and will be followed by a social networking event with wine, beer and hors d'oeuvres. The presenters will participate and the technical demonstrations will remain active for those who wish to continue discussions after the workshop.

The registration fee for the workshop is $400 reducing to $300 for PSMA members and IEEE PELS members. The day of workshop registration fee will be $425 reducing to $325 for PSMA members and IEEE PELS members if seating is available. There is an option at a nominal fee of $5 to obtain Continuing Education Units (CEUs) for attending in this workshop.

Breakfast and lunch will be provided as part of the workshop and electronic copies of the technical lecture presentations and technology demonstration presentations will be made available to workshop participants.

The latest agenda, registration, and additional information is available at www.psma.com/technical-forums/capacitor/workshop.

Provided by members of the Capacitor Workshop Organizing Team:
Pierre Lohrber, Wurth Electronics
Fred Weber, Future Technology Worldwide

Early bird registration ends March 31!
16-18 June 2020
ASSIST Center, North Carolina State University

"Building the Ecosystem for Powering the Internet of Things"

Three-day program will build on the highly acclaimed 2018 inaugural event;
Industry thought-leader keynote speakers announced  

SMA

EnerHarv 2020 will build upon the inaugural event held in 2018 at the Tyndall National Institute in Cork, Ireland. The mission remains the same - to create a focal point for a community of experts and users of energy harvesting & related technologies to share knowledge, best practices, roadmaps, experiences and to create opportunities for collaboration primarily in the wireless IoT edge device sector.

"EnerHarv was set up as a key biennial event to help solve the 'trillion sensor challenge' of 2025, recognizing that most of the world's IoT devices will require a portable power source such as a battery needing to outlive the device that it powers," commented Brian Zahnstecher, PSMA Energy Harvesting Committee and EnerHarv Co-Chair.

The slate of keynote speakers has already been announced and the overall program is well in development with a strong organizing committee in place. Baoxing Chen, ADI Fellow at Analog Devices will present "Powering the IoT, an Energy Harvesting Perspective." Veena Misra, Distinguished Professor at NC State University will discuss "Self-Powered Wearable Sensors for Health and Environmental Monitoring." Sally Safwat Amin, Research Scientist at Intel's Technology, Systems Architecture & Client Group will discuss "Towards Miniaturized Energy Harvesting Platform for Powering Net-Zero Energy Systems."

Attendees will learn of the many constituents of existing and emerging 'power IoT' solutions and how to apply these in a system-optimized way creating high impact solutions for a broader range of applications. Through technical presentations, networking, panel sessions, viewing real life demos and participating in discussions, attendees will gain a step function increase in their knowledge and ability to develop/gain access to energy harvesting powered solutions.

EnerHarv 2020 is also being supported by the China Power Supply Society (CPSS), the European EnABLES Project and the IEEE Power Electronics Society (PELS).

Visit http://www.enerharv.com to learn more. Proceedings from the inaugural workshop, EnerHarv2018, can also be found here in an open source repository.

	Provided by
Mehmet Ozturk, NC State (General chair)				Brian Zahnstecher, PowerRox (General co-chair)

June 22-24, 2020
Osaka University, Japan

Registration is Now Open

The 3rd biennial 3D-PEIM Symposium has invited world-class experts representing a far-reaching range of disciplinary perspectives who are advancing the development of future 3D power electronics systems. The experts are Industry Professionals and Academics engaged in R & D of power electronics packaging design, and manufacturing processes. The Symposium encompasses additive, embedded, co-designed, and integrative packaging technologies with sessions that address mechanical, materials, reliability, and manufacturability issues using small, smart, power-dense components and modules.

This Symposium will provide attendees an excellent opportunity to gain insight or to broaden their expertise in 3D power electronics packaging and integration. The Symposium schedule is arranged to provide ample time between sessions for attendees to share ideas, progress, and challenges with leading members of Universities, companies from industry, and representatives from international associations and societies. On the last day of the Symposium, attendees are invited on a guided tour of the Osaka University Laboratory for Power Electronics and Electrical Energy and the Graduate School of Engineering Gallery.

General Chair Professor Tsuyoshi Funaki states, "I am glad we are the first to host the 3D-PEIM Symposium outside the USA. It is very appropriate that 3D-PEIM is held here because there are many power device and peripheral packaging material manufacturers in Japan. I believe this Symposium will be an amazing experience for the attendees because we are assembling world prominent experts in power electronics packaging and manufacturing. I also believe that all attendees will gain significant advance packaging knowledge through discussions at this Symposium".

The Symposium schedule will include Plenary and Keynote Presentations, Technical Sessions, new this year - a Sponsors Round Table Discussion, Tabletop Demonstration Exhibits and Networking & Laboratory Tours. The technical program and session chairs are:

• S1 Plenary I: Tsuyoshi Funaki, Osaka University, Japan
• S2 Additive Manufacturing: Patrick McCluskey, University of Maryland, USA and Douglas Hopkins, North Carolina State University, USA
• S3 Systems Integration & Thermal Management: Christina DiMarino, Virginia Tech, USA
• S4 Plenary II: Katsuaki Suganuma, Sanken Osaka University, Japan
• S5 Multiphysics Design and Tools: Michihiro Shintani, Nara Institute of Science and Technology (NAIST), Kansai Science City, Japan
• S6 Materials: Jason Rouse, Sekisui America, USA
• S7 Manufacturing Technologies: John Bultitude, Kemet Corporation, USA
• S8 Sponsors Session: Minora Ueshima, Daicel, Japan
• S9 Quality and Reliability: Steven Martell, Nordson Sonoscan, USA
• S10 Heterogeneous Integration of Components: Cyril Buttay, Laboratoire Ampère, France

The complete Symposium agenda and latest updates are available on the 3D-PEIM Website: http://www.3d-peim.org/program/

If you are interested in being a 3D-PEIM 2020 PARTNER, contact info@3d-peim.org

Some feedback from attendees at the 2016 & 2018 Symposiums:

• "The 3D-PEIM brings together a unique set of participants – those involved in power packaging who actually know and care about manufacturing and reliability."
• "Most valuable is the breadth of topics. I don't consider myself an expert in many topics presented so, touching on multiple topics is very helpful."
• "The keynote speeches were most valuable, providing an excellent recent update on embedded technologies."

Register now at http://www.3d-peim.org/registration/

We look forward to seeing you in Osaka, Japan, this coming June.

For further information, contact the 3D-PEIM Symposium organizers at http://www.3d-peim.org/contact/ or Sponsor PSMA at power@psma.com

General Chair, 3D-PEIM Symposium 2020 Prof. Tsuyoshi Funaki, Osaka University
Technical Program Co-Chairs:
Prof. Katsuaki Suganuma, Osaka University	Minora Ueshima, Daicel, Japan	Prof. Guo-Quan (GQ) Lu, Virginia Tech USA

Organizing, Financial and Technical Partners:

University of Pennsylvania, Philadelphia, PA
October 25 – 28, 2020
Sponsored by PSMA and IEEE PELS

he seventh edition of the biennial International Workshop on Power Supply on Chip (PwrSoC) workshop returns to North America on October 25 thru October 28 2020 will be held at the Singh Center for Nanotechnology on the campus of the University of Pennsylvania in Philadelphia PA.

PwrSoC is the leading international forum for the discussion of the challenges and opportunities in technology, business and supply chain, with focus on advancing the miniaturization and integration of power conversion and power management solutions. The upcoming workshop will feature presentation and dialog sessions of advanced technologies with global academic and industry experts aimed at miniaturizing power management solutions through system architecture, circuits and topology, packaging, and passive components. The Power Sources Manufacturers Association (PSMA) and IEEE Power Electronics Society (IEEE PELS) are joint financial and technical sponsors for the  workshop.

Since the inaugural Power Supply on Chip workshop initiated by Cian O'Mathuna and hosted by Tyndall National Institute, PwrSoC has grown from discussion of initial concepts to discussion of commercialized products and technology roadmaps that evolved from the initial concepts of earlier workshops to the most recent workshop in Hsinchu Taiwan in 2018. The workshop series has evolved to encompass presentations that encourage dynamic and productive dialog between academia and industry. With each workshop there continues to be research oriented presentations of new technologies complemented by a growing number of attendees from industry companies representing semiconductor equipment manufacturers thru foundry and fabrication facilities, out sourced assembly and test companies, passive component suppliers and power converter companies that address application and near term and long term product roadmaps.

In 2020, PwrSoC returns to North America at the Singh Center for Nanotechnology on the campus of the University of Pennsylvania in Philadelphia, PA centrally located on the I95 corridor of the US east coast. PwrSoC 2020 will be chaired by an experienced team with Prof. Mark Allen as the General Chair and Matt Wilkowski and Hanh-Phuc Le as the Technical Program Co-Chairs.

The PwrSoC 2020 Workshop will continue as a single-track format allowing attendees access to all the latest developments in systems and integration, active and passive components, system integration, packaging and manufacturing, granular power topologies and control.

The technical presentation sessions are a combination of lecture style presentations and interactive panel Q & A dialog sessions and will be complemented with interactive poster session demonstrating the wide range of perspectives from emerging system and application requirements, research initiatives and industry commercialization.

Throughout its history, the workshop has spotlighted advanced technologies to build granular power supplies and compelling demonstrations of commercialized products that make a clear case for power on chip and power in package (PSIP) technologies becoming more prominent and mainstream.

General Chair Mark Allen points out "The venue of Singh Center for Nanotechnology on the campus of the University of Pennsylvania offers a unique opportunity to pursue advanced component and device fabrication technologies towards supporting market applications on the horizon being developed elsewhere on campus." Supporting the ambition to identify the solutions that PwrSoC and PSIP technology can contribute towards new applications, there will be an opportunity to tour various labs on the campus of UPENN including the GRASP Lab (robotics, automation, sensing & perception applications), Penn Electric Racing (electric vehicles) in addition to the facilities of the Singh Center for Nanotechnology

The technical program chairs for the PwrSoC2020 are Professor Hanh-Phuc Le of University of California at San Diego and Matt Wilkowski of EnaChip. Both have been presenters, session chairs and program chairs for past PwrSoC workshops. They have assembled a team of world-renowned experts, innovators and pioneers of the PwrSoC technology to chair the workshop's nine sessions:

• Plenary Session - Jose Cobos, University Polytechnic Madrid
• Systems and Applications - Francesco Carobolante, IoTissimo
• Topologies and Control - Jason Stauth, Dartmouth College
• Wideband Gap Integration - Brian Ma, University Texas Dallas
• Integrated Capacitors & Energy Storage - Medhi Jatlaoui,, Murata
• Integrated Magnetics - Masahiro Yamaguchi, Tohoku University Japan
• Sys Integ Manufacturing and Packaging - Baoxing Chen, Analog Devices
• Granular Power - Santosh Kulkarni, Dialog Semiconductor
• Posters - Minjie Chen, Princeton University

This year a panel session will be introduced to explore the circumstances and thresholds to connect the emerging trends and developments of the technology with market opportunities and associated investments. Anyone interested in being a presenter or participating in the technical organization of the workshop should contact Hahn Phuc Le or Matt Wilkowski directly.

As part of identifying a theme for this year's workshop, Matt Wilkowski has stated that "The technical objectives of the 2020 workshop are to showcase the contributions of technologies from a diverse global representation of innovators and pioneers from both research and industry towards recent products and products on the horizon for both PSiP and PwrSoC applications. A great deal of progress has been inspired by the first six workshops and there is still a great amount that can be accomplished. As part of the process to identify additional presentation topics, an industry session titled 'PwrSoC Driving Lead Edge Components' with presentations by the session chairs of the 2020 workshop will take place at APEC, IS20 on Thursday March 19th. We are looking forward to another high energy workshop that will continue to drive power efficiency, size, reliability, quality and cost."

The planning of the technical program, supporting activities as well as identifying workshop partners to contribute to its success are in process. If interested in being a workshop partner, please contact the workshop financial chair, Trifon Liakopoulos, at trifon@enachip.com

With the intention of continuing the tradition of the enthusiasm, market relevance and success of past workshops, we are looking forward to another successful PwrSoC 2020 in Philadelphia, PA. The latest information and updates on PwrSoC2020 are available at pwrsocevents.com.

General Chair:
    Dr Mark Allen  mallen@seas.upenn.edu

Technical Program Co-Chairs
  Matt Wilkowski mwilkowski@enachip.com
  Prof. Hanh-Phuc Le hanhphuc@ucsd.edu

he 8th Annual IEEE / PMSA Workshop on Wide Bandgap Power Devices and Applications (WiPDA) will be held in Redondo Beach, California from October 25 to 27, 2020. This annual event provides engineers and scientists with opportunities to share their expertise in wide bandgap (WBG) semiconductor technology. This year's workshop features tutorials on October 25, 2020.  The following two days will host keynote sessions, panel sessions, technical sessions, and a poster session that covers four technical tracks: silicon carbide (SiC) power devices, SiC applications, gallium nitride (GaN) power devices, GaN applications, and new this year, Gallium Nitride (GaN) RF devices and applications and International Technology Roadmap for Wide Bandgap Power Semiconductors) (ITRW).  Topics in emerging WBG materials will also be solicited.  

There will be many opportunities to network with leading WBG specialists in industry,  academia and national laboratories, especially at the Industry and Sponsors Exhibition, which occurs simultaneously with the workshop.  A reception will be held October 25, 2020 and a banquet is planned for October 26, 2020.

The workshop is brought to you by the IEEE Power Electronics Society (PELS), the Power Sources Manufacturers Association (PSMA), and the IEEE Electron Devices Society (EDS).  The General Chair is Sameh Khalil, Lead Principal Engineer, GaN Device Reliability and Product Engineering Management at Infineon Technologies.  He is supported by Vice Chair Helen Li, Professor of Electrical and Computer Engineering Department, FAMU-FSU college of Engineering

Key Dates:

• June 1, 2020:             Abstract submission deadline.
• July 17, 2020:            Notification of the acceptance.
• August 28, 2020:       Submission to mentor
• September 9, 2020:   Final paper submission deadline for workshop proceedings.

Call for Abstracts:
The abstract submission portal will open mid spring to accept authors' manuscripts.  Researchers are encouraged to submit their latest findings on the design and fabrication of WBG power devices, their insertion in power electronics circuits/systems, and on technology of SiC, GaN, their reliability and other emerging, high performance WBG power semiconductors. 
 
Authors and speakers are encouraged to submit their latest research findings in this WiPDA world-renown symposium. For  abstracts proposals, the technical topics of interest include:

• Heteroepitaxial & Bulk Materials Growth
• Gate Dielectrics & Surface Passivation
• Device Structures & Fabrication Techniques
• Device Characterization & Modeling
• Very-High Efficiency Or Compact Converters
• Safe Operating Areas Of Wide Bandgap Devices, Including Short Circuit, Spike, &Transient Tolerance
• Harsh Environment (High Temperature) Operation & Reliability
• Packaging Power Modules & ICs
• Hard-Switched & Soft-Switched Application Analysis
• Gate Drive & Other Auxiliary Circuits
• High-Performance Passive Components
• Applications in Renewable Energy & Energy Storage, Transportation, Industrial Drives, & Grid Power Systems
• Wide Band Gap System Design Philosophies & Strategies
• Radio Frequency (RF) GaN (NEW)
• Technology Roadmap of Wide Bandgap Including Devices, Applications and Packaging (NEW)

We look forward to seeing you this fall in Redondo Beach, California, USA.

Provided by: Renee Yawger WiPDA 2020 Publicity Chair

s specified in the European Directive 2015/863 dated 22nd of July 2019, electronic equipment manufacturers will have to comply with the third revision of the Restriction of Hazardous Substances (RoHS), referenced as RoHS 3. All categories of electrical and electronic equipment are affected except medical devices and monitoring and control instruments, for which restrictions will apply from the later date of 22 July 2021 to take into account their longer innovation cycles. The "Revision 3" adds four additional restricted substances, listed under phthalate, to the original list of six (see table 1).

Table 1– From RoHS 1 to RoHS 3

In 2010 some phthalates were on the REACH candidate list or listed in REACH Annex XIV as subject to the authorization process. They were also included in the European Commission's proposal for the recast of the EU Directive on the restriction of hazardous substances (RoHS) in electrical and electronic equipment as priority substances to be assessed for potential restriction, which eight years later is now happening.

Since the original listing in REACH, and in the candidate list of Substances of Very High Concern for authorization (SVHC), the risk and toxicity of the four substances, listed below, have been researched by international laboratories.

• Bis (2-ethylhexyl) phthalate (DEHP)
• Benzyl butyl phthalate (BBP)
• Dibutyl phthalate (DBP)
• Diisobutyl phthalate (DIBP)

The results of more than 10 years tests and investigation exhibit a very high hypothesis that the effects of exposure to phthalates may affect human reproduction, development and risk of cancer. These results have motivated the European Commission to move the four phthalates from "Observation" to "Restriction and Interdiction".

Phthalates are a group of chemical substances used to soften and increase the flexibility of plastic and vinyl. They are commonly used in all industries from food packaging to cables, in insulation tapes and in some resins, in short they are almost everywhere (see table 2).

Table 2 – The four banned phthalates are widely used across the whole industry

As was the case for the previous six restricted substance in RoHS 1st edition and RoHS 2nd edition, due to the high usage of phthalates in electronics equipment - including in power supplies - designers must work in close cooperation with their suppliers to substitute such materials with "phthalate free" elements and components.

Due to some industries (e.g. medical) being more sensitive to the risk of phthalates affecting people (patients), as long ago as 2010 they were informing and educating their suppliers about the forthcoming regulations, thus anticipating the demand for parts with less than 1000 ppm of the identified substances listed in REACH and SVHC.

Today, a number of companies are offering RoHS 3 compliant substitutes but there is a huge legacy lagging in the supply chain which will require some pretty intense work to ensure that all products delivered after 22nd July 2021 are compliant, which for newly made products might not be a major problem but it could be for products held in stock all over the world.

Are my products complying and what about legacy?

Since the European Directive 2015/863 was released on the 31st March 2015, designers have worked with their suppliers to guarantee that all new products pre-comply with the forthcoming regulation, but in some case it has been difficult to replace certain parts (e.g. insulation tape for high voltage transformers), thus delaying the compliance of some products. In three years' time suppliers will have implemented different processes and substances to replace banned phthalates, but there are few questions remaining on special components or parts.

However, if in new products the level of banned phthalates is reduced to below 1000 ppm, the doubt remains for items laying in stock. To be on the safe side a number of companies have taken the decision to run samples through an X-Ray Fluorescence (XRF) analyzer, and if this is not deemed enough to use Fourier Transform Infra-red Spectroscopy (FTIR) testing methods and sometimes Scanning Electron Microscopes (SEM).

The cost for such analysis could be substantial however, in the context of present day market conditions and the effects of component shortages, scraping products without knowing if the level of the four phthalates below or over the 1000 ppm threshold might cost even more money.

Repair and maintenance, what should I do?

As specified in the Directive, the restriction of DEHP, BBP, DBP and DIBP shall not apply to cables or spare parts for the repair, the reuse, the updating of functionalities or upgrading of capacity of electrical and electronics equipment placed on the market before 22 July 2019, and of medical devices, including in vitro medical devices, and monitoring and control instruments, including industrial monitoring and control instruments, placed on the market before 22 July 2021.

RoHS-1, RoHS-2, RoHS-3, what's next?

"REACH aims to improve the protection of human health and the environment through the better and earlier identification of the intrinsic properties of chemical substances." That means that research on toxicology and its impact on health and the environment will continue in order to identify risks.

As well, the European Chemical Agency has worked on a "Roadmap for SVHC identification and implementation of REACH Risk Management measures from now to 2020" which gives an EU-wide commitment to ensure that all relevant, currently known substances of very high concern (SVHC) are included in the candidate list by 2020. The objective of the SVHC Roadmap is to screen to identify new substances of concern, and to analyze the risk management options (RMO) appropriate to the particular substance of concern.

In today's business environment, electronics engineers must continuously monitor the evolution of REACH and SVCH. With the growing concerns about health and the environment we can expect more substances to be added to the RoHS list, which in some cases may prove to be extremely challenging.

As in many other situations, knowing your industry, being innovative and investing in new technologies is probably the only way to go.

Provided by Patrick Le Fèvre Chief Marketing and Communications Officer, Powerbox

Editor's Note: Article reproduced with courtesy of Power Systems Design and Powerbox (PRBX)

any products including power supplies and household products are connected to the ac line. Within these products we find the so-called X capacitors used to provide line filtering. If no measures are taken to discharge these capacitors, they can retain a high-voltage charge even after ac power is removed from the product.

So, when the consumer removes the ac power cord plug of one of these products from the ac socket, there may be significant voltage remaining on the X capacitors. This high voltage may cause a shock to the consumer if their fingers touch the metal prongs of the ac plug during or shortly after its removal from the wall socket.

There are several regulations from the IEC/EN to prevent the consumer from being shocked if their fingers should touch the metal prongs of the ac power plug. These regulations are based on the IEC60335^[1], IEC62368^[2], and IEC/EN/ UL 60950^[3] standards.

IEC62368 applies to IT equipment and video and audio equipment, while the IEC60335 concerns appliances. Meanwhile, UL/EN/IEC 60950 is the harmonized standard for power supplies. UL has regulated the discharge of X capacitors for many years for TVs, where the X capacitor typically had a resistor value between a 1.0 MΩ and 2.2 MΩ to discharge them.

Satisfying the safety requirements for the discharge of X capacitors would be straightforward were it not for the energy efficiency standards, which are pervasive and over time are becoming more demanding. The simple act of using discharge resistors in a product's power supply can raise its power consumption under no-load or standby conditions to the point where it may exceed the mandated levels. This article discusses both the safety and energy efficiency requirements, looks at the different circuit approaches to discharging X capacitors and how well they do in terms of satisfying the energy efficiency regulations.

While the focus here is mainly on the X capacitors, note that there also Y-capacitors. Nick Davis ^[4] describes these X and Y capacitors along with the IEC ratings in his article, "Safety Capacitors First: Class-X and Class-Y Capacitors". 

The Y capacitor is connected from the mains to ground while the X capacitor is connected across the ac power mains. Fig. 1 shows both capacitor types. The Y capacitors are often ceramic and less than 0.0033 µF or 3.3 nF. The X capacitors cited in the standards are greater than 0.1 µF. These X capacitors are to be discharged to less than 34 V peak in 1 second after the power plug is removed from the socket. While it's only the X capacitors that pose the safety hazard, the Y capacitors are important to the discussion because they contribute to the ac leakage current.

Therefore, they also impact a product's ability to meet the energy efficiency rules.

Fig. 1. Generic schematic showing the front end of a power supply including discharge resistors, R, common-mode choke, differential-mode choke, X film capacitors, and Y ceramic capacitors for a product. The X capacitors are for EMI control, and the Y capacitors are limited in value due to leakage current to ground.

Discharge Resistor Power Consumption

While a product is plugged in, any discharge resistors associated with X capacitors will be continuously dissipating power, contributing to the product's continuous power loss.

The power loss produced by an X capacitor discharge resistor is a function of the ac line voltage and the resistor value:

Power Loss = (Vac Line)2/R

In the U.S., Canada, and Mexico, Vac is 120 Vrms nominal and R is typically 1 MΩ, so:

Power Loss = 0.0144 W or 14.4 mW

In Europe, Vac is 230 Vrms nominal and R is typically 1 MΩ, so:

Power Loss = 0.0529 W or 52.9 mW

This wattage seems small until you take into account the standby power requirements for some products. The U.S. Department of Energy ^[5] and the California Energy Commission ^[6] have new requirements for standby energy consumption that are, in the most stringent case, less than 2X the loss imposed by the discharge resistor. The no-load mode power is given below in Table 1.^[7]

Table 1. Efficiency requirements for single-voltage power supplies.

Discharge Time for X Capacitors

According to IEC 60335^[1] and IEC 62368^[2], the voltage across the X capacitors must be below 34 V, in less than 1 second. The X capacitors are part of the line-conducted EMI filter, and the values of these capacitors are determined at the timeline-conducted EMI testing is performed. The design engineer should use place holders on the pc board so the different values can be tried.   

Table 2 was created to show the value of the two resistors in series in Fig. 1 to discharge the total of X2 capacitors. The value of the X capacitors ranges from 0.1 µF to 5.6 µF. The voltage used for the calculation was 230 Vac. In addition, the power dissipation was calculated for the resistors in series. The value of the capacitance is the sum of the EMI capacitors including X-1, X-2, X-3 and the MOV capacitance. 

Table 2. Discharge resistor values for power supply circuit in Fig. 1.

The power dissipation shown exceeds the 0.1 W in the U.S. Department of Energy's standby power no-load regulations for some low-wattage power supplies and battery chargers of cell phones. To reduce the power dissipation in the standby mode, the semiconductor industry created X2 discharge ICs such as the Power Integrations CAPZero ^[8] family of parts. In a nutshell, these ICs disconnect the discharge resistors from the circuit when a product is plugged in and reconnect these resistors at the time ac power is removed. In this way, the discharge resistors are not dissipating unnecessary power that contributes to the product's standby or no-load power consumption.

Other companies have similar parts such as the TEA1708^[9] and HF81.^[10] This approach is shown in Fig. 2, which is taken from the Power Integrations Application Note AN-48.^[15]

Fig. 2. CAPZero X capacitor discharge IC approach. While the product is plugged in, the CAPZero IC disconnects the discharge resistors so that they are not dissipating power.

The semiconductor industry has found other ways to discharge the X capacitors and these methods have been implemented in pulse width modulation control ICs for the power supplies. This approach eliminates a separate X capacitor discharge control IC.

Some of these ICs were found via web search using "X capacitor discharge" as the search topic: FAN6756,^[11] NCP12400,^[12] TEA19363,^[13] and BM1C102F. ^[14] This is not a complete list. The PWM control IC approach shown in Fig. 3 is taken from the NCP12400.

The application notes AN-48^[15] from Power Integrations was helpful in determining the values of the discharge resistors and the time to discharge the X capacitors. The X capacitors used in the EMI or RFI filter capacitors can be classified as either X1 or X2 depending upon the construction of the capacitors; reference 4 explains the difference and uses of these capacitors.

Fig. 3. The discharging of the X capacitors using the NCP12400.

Summary

This article explains why there are discharge resistors across the X capacitors of a product. The resistor is used to discharge the voltage left on the capacitor to a safe level so as not to cause an electrical shock to the consumer when the product in unplugged. The time allowed to discharge the capacitor is 1 sec.

However, whenever a product is plugged in, the discharge resistors are consuming power, unless there is a control IC used to eliminate the resistors' constant current draw. Without such a control IC, the power draw of the discharge resistors contributes to the product's power consumption in the standby or no-load mode and may exceed the power consumption mandated by regulatory agencies, including the U.S. Department of Energy and the California Energy Commission. Similar regulations apply in Europe. 

References:

1. IEC 60355.
2. IEC 62368.
3. UL 60950-1.
4. "Safety Capacitors First: Class-X and Class-Y Capacitors" by Nick Davis, All About Circuits, May 06, 2019.
5. U.S. Department of Energy.
6. California Energy Commission.
7. https://ac-dc.power.com/green-room/regulations-agency/us-doe-eisa2007-energy-independence-and-security-act/ 
8. CAPZero-3 and CAPZer0-2 product page.
9. TEA1708T data sheet.
10. HF81 data sheet.
11. FAN6756 product page.
12. NCP12400 product page.
13. TEA19363 data sheet.
14. BM1C102F data sheet.
15. "CAPZero Design Considerations," Power Integrations application note AN-48.

Acknowledgements

I would like to thank Edward Ong of Power Integrations and Carl Walding of ON Semiconductor for their input to this article. - Jim Spangler

Authors:

Kevin Parmenter Director of Applications Engineering Taiwan Semiconductor America

Jim Spangler President Spangler Prototype Inc. (SPI)

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