ZKZ 64717

10-09ISSN: 1863-5598

Electronics in Motion and Conversion October 2009

A Goodcatch!

SAMPLES AVAILABLE!

Features50A gate drive current2 x 6W output power+15V/-10V gate voltageSeparated gate paths (on/off)150kHz switching frequency80ns delay time±1ns jitter3.3V to 15V logic compatibleIntegrated DC/DC converterShort-circuit protectionEmbedded paralleling capabilitySuperior EMC (dv/dt > 100V/ns)

The new SCALE-2 dual driver core 2SC0650P combines highest power density with broad applicability. The driver is designed for both high-power and high-fre-quency applications. It is suit-able for IGBTs with reverse voltages up to 1700V and also features a dedicated MOSFET mode. Intelligent paralleling allows all forms of parallel connection of high-power modules. Multi-level topologies are also supported. The 2SC0650P offers all

ultra-short signal delay times. CONCEPT’s patented

the highest requirements.

2SC0650P Dual Gate Driver

CT-Concept Technologie AG, Renferstrasse 15, CH-2504 Biel, Switzerland, Phone +41-32-344 47 47 www.IGBT-Driver.com

C O N T E N T S

www.bodospower.com October 2009

Viewpoint

The Golden Leaves of Fall and Show Time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

Events . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

News . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-8

Blue Product of the Month

2.25-MHz, 1-A DC/DC Converter for USB-Powered Applications

Texas Instruments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Guest Editorial

Semiconductors Hold Key to Electric and Hybrid Vehicles

By Dr. Henning Hauenstein, VP and GM, Automotive Products Business Unit, International Rectifier Corp . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Market

Electronics Industry Digest

By Aubrey Dunford, Europartners . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Market

New Market Drivers for Telecom

By Linnea Brush, Senior Research Analyst, Darnell Group . . . . . . . . . . . . . . . . . . . . . . . . 16-17

Cover Story

ISOPLUSTM-DIL Series – Designed for Highest Reliability

By Andreas Laschek-Enders, Dipl. Physiker, Produkt Marketing, IXYS . . . . . . . . . . . . . . . 18-20

MOSFET

Extending the OptiMOS™3 Power MOSFET Family

By Dr. Ralf Siemieniec and Dr. Oliver Häberlen, Research & Development, and Juan Sanchez, Technical Marketing, Infineon Technologies . . . . . . . . . . . . . . . . . . . . 22-24

MOSFETs

How Low Can You Go?

By Dr Georges Tchouangue, Principal Engineer, Power Semiconductors, Toshiba Electronics Europe GmbH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26-27

EMC

EMC Filters, new applications thanks to lower leakage current

By Volker Scharrer, EPCOS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28-29

Technology

A New Approach to Induction Heating Design

By Cesare Bocchiola, International Rectifier . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30-31

Technology

Mixed Signal and Power Integration Packaging Solutions

By Jim Gillberg, Fairchild Semiconductor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32-34

Power Management

The Correct Power Supply

By Oliver Kistner, Schroff GmbH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36-37

Measurement

High Speed Testing of Power Semiconductors

By Gérard Cuénoud, LEMSYS SA, Switzerland . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38-40

Design and Simulation

Thermal Simulation Predicts the Junction Temperature and Life Time of Semiconductors

By Tobias Hofer, Negal Engineering GmbH Switzerland . . . . . . . . . . . . . . . . . . . . . . . . . . . 42-43

Design and Simulation

Fit More Watts Into the Same or Less Amount of Space

By Herbert Endres, Molex . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44-45

New Products . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46-48

Ready formass production

Taking open loop technology to the next level: introducing a surface mount device.

HMS

Automatic assemblyDedicated LEM ASIC insideCompatible with themicrocontroller or A/D converter, reference provided outside or forced by external reference, 5 V power supplyImproved offset and gain drifts and enhanced linearity over traditional open loop designsVRef IN/OUT on the same pin8 mm creepage and clearance distances + CTI: 600No insertion lossesSeveral current ranges from 5 to 20 ARMS

SPS/IPC/

Drives

Hall 1.528

2 Bodo´s Power Systems® October 2009 www.bodospower.com

TThhee GGaalllleerryy

national.com/led

High Performance. Low Power.Energy-Efficient LED Lighting Solutions National’s new low-side, constant-current LED driver offers integrated thermal control

to increase system reliability. The thermal foldback feature of the PowerWise® LM3424

LED driver provides a more robust thermal design to extend the life of the LEDs, making

it an ideal solution for a variety of indoor/outdoor lighting and automotive applications.

Thermal ManagementSince thermal design greatly

impacts the light output

and lifetime of the LEDs,

a well-designed thermal

system is critical. The

LM3424’s thermal foldback

feature eliminates the

need for external thermal

management circuitry,

allowing for a more robust

and reliable thermal system

and extending the life of the

LEDs.

Easy to UseWith National’s WEBENCH®

LED Designer online tool,

designers can use the

LM3424’s thermal foldback

feature to visualize the

design’s behavior at user-

selected LED temperature

breakpoints for easy and

quick development of

a thermal management

system.

Flexible DesignNational’s LM3424 LED

driver, with a wide input

voltage range, can be easily

configured in buck, boost,

buck-boost, and SEPIC

topologies with minimal

adjustments. Driving a

maximum of 18 LEDs in

one string, the LM3424

gives designers flexibility

while providing up to 96%

efficiency and accurate

current regulation with less

power and heat dissipation.

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Bodo´s Power Systems® October 2009 www.bodospower.com

Summer comes to an end. The Baltic Sea

turns colder and only the hardiest among us

go for a swim. We approach Indian Summer

and witness as the leaves quickly turn gold-

en, before continuing on to brown. At times it

takes only one stormy night and the next

morning they cover the meadow. This is the

perfect time to sneak out and go south for a

conference or meeting, and Barcelona in

Spain fits the bill beautifully. The EPE Con-

ference, driven by the Universities, gives

new insight into progress in modern power

electronics. Efficiency is what counts in

reducing power consumption and renewable

energy is the key to conserving the

resources of mother earth.

Photovoltaic and wind power sources are

growing areas. Wind power is going off-

shore into deep water regions. Here the con-

ditions for reliable operations challenge engi-

neers – but challenge is the life of an engi-

neer, otherwise work is not fun. Photo-

voltaics will enter into any region that has

reasonable sunshine. New control tech-

niques will make photovoltaics more efficient

under shaded conditions. It is up to govern-

ments worldwide to provide financial stimu-

lus for photovoltaics – similar to the incen-

tives for new private cars.

Nuclear power has demonstrated risks all

around the world, and has highlighted the

inability of politicians to understand both the

physics and risks involved. The half-life for

most of the nuclear isotopes is much longer

than a politician’s life time. Politicians have

been talking for more than half a century and

have not yet paved a way to store nuclear

rubbish. While the cost for cleaning up tem-

porary storage areas remains unknown, we

can be certain that, in the end, this cost will

be paid by us, the taxpayers.

Recovery of wasted energy is a very impor-

tant engineering aspect of any application. It

has begun with electric hybrid vehicles, but

has been very common in mass transporta-

tion traction systems. The recovery of heat

from used air or water can only be done effi-

ciently with the ability of modern control

electronics to compute complex data.

We must use engineering resources to build

a secure and sustainable future for our chil-

dren. The role of legislatures is to provide

support through strict laws.

Modern semiconductor materials are con-

tributing to higher efficiency and better sys-

tems designs. Silicon Carbide and Gallium

Nitride materials are going step by step into

higher efficiency inverter designs. The ECPE

work shop in Barcelona has updated trends

and achievements thus far.

For all of you that have not been to

Barcelona to pick up crucial information, we

have my publication in print each month, and

in pdf form from my website, in addition to

the e-newsletter twice monthly for instant

updates. The production shows, SEMICON

Europa and Productronica, are just ahead

with their indications of future directions.

There is no better way to communicate. We

all share one world. As a publisher I serve

the world: one magazine, on time, every

time.

My Green Power Tip for the coming

months:

Rather than leaving your kids in front of the

TV screen, take a book and read a story for

them. This helps to get them into a dialogue

with you, and develops their imagination. By

the way, it also saves electricity if you did not

forget to turn off the TV.

See you next time in Dresden at SEMICON

Best regards

The Golden Leaves ofFall and Show Time

Events

SEMICON Europe,

Dresden, Germany,

October 6-8

http://semiconeuropa.org/

Productronica,

Munich, Germany,

November 10-13

http://productronica.com/

SPS/IPC/DRIVES,

Nuremberg, Germany,

November 24-26

http://mesago.de/sps

Power Electronics,

Moscow, Russia,

December 1-3

www.powerelectronics.ru

APEC 2010,

Palm Springs, CA,

February 21-25,

www.apec-conf.org

V I E W P O I N T

4

A MediaKatzbek 17a

D-24235 Laboe, Germany

Phone: +49 4343 42 17 90

Fax: +49 4343 42 17 89

editor@bodospower.com

www.bodospower.com

Publishing EditorBodo Arlt, Dipl.-Ing.editor@bodospower.com

Creative Direction & ProductionRepro Studio Peschke

Repro.Peschke@t-online.de

Free Subscription to qualified readers

Bodo´s Power Systems

is available for the following

subscription charges:

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world wide

Single issue is 18 €

subscription@bodospower.com

circulation

printrun

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A Media and Bodos Power Systems

assume and hereby disclaim any

liability to any person for any loss or

damage by errors or omissions in the

material contained herein regardless of

whether such errors result from

negligence accident or any other cause

whatsoever.

6 Bodo´s Power Systems® October 2009 www.bodospower.com

N E W S

Distributor RS Components announces the

expansion of its test and measurement

range with Agilent Technologies. The

increased range provides advanced perform-

ance in multimeters, oscilloscopes, function

generators and bench power supplies.

Products are optimised for accuracy, func-

tionality and ease-of use to ensure users

can record accurate data results when test-

ing their applications.

Among the new introductions, highlights

include the DSO1000 series oscilloscopes,

with bandwidths between 60MHz and

200MHz, available in two or four channels.

The U8000 series single-output DC power

supplies, a low cost expansion of the best

selling Agilent E3600 series, and the 33200A

series of function/arbitrary waveform genera-

tors, introduced for engineers who need

lower-frequency signals without sacrificing

accuracy.

The range of handheld instruments has been

significantly upgraded with additions includ-

ing the U1701A capacitance meter and

U1731A/U1732A LCR meters, giving engi-

neers easy and low cost access to compo-

nent testing. The two-in-one functionality of

the U1401A multi-function calibration/meter

lets technical staff travel light when carrying

out calibration, testing or service, while the

U1253A handheld digital multimeter (DMM)

is the first to use an organic light-emitting

diode (OLED) display to ensure crystal clear

viewing.

www.rs-components.com

RS Expands its Agilent Test and Measurement Range

The Fraunhofer Institute for Solar Energy

Systems ISE will hold an international sym-

posium on intelligent energy management

for non-residential buildings on October 1st

2009 in Berlin. The event will offer energy

and building professionals an overview of

the latest technology and future trends.

Since 2007, the EU's Building EQ project,

which will end in December 2009, has been

concerned with intelligent energy manage-

ment processes in existing buildings.

The EU buildings directive (EPBD – Energy

Performance of Buildings Directive) has

specified Europe-wide standards for building

certification since 2006. National legislation

has built upon the EPBD framework. Fur-

thermore, in Germany, the energy conserva-

tion ordnance (ENEV) will be updated on

October 1st 2009. Building owners are

required to show energy certification docu-

ments for their buildings prior to rental or

sale. As sensible as certificates are, they are

not an adequate means of adhering to certi-

fied values and, in turn, ensuring climate

protection effects. Buildings require constant

controlling to ensure compliance with certi-

fied values.

www.ise.fraunhofer.de

www.BuildingEQ.eu

Intelligent Energy Management in Buildings

CUI Inc is now a member of the Power

Management Bus Implementers Forum

(PMBus). PMBus is an industry standard

developed to allow power converters to com-

municate over a digital bus. Current PMBus

adopters include semiconductor companies

such as TI, Infineon, and Intersil, power sup-

ply companies like Delta and Artesyn, and

OEMs like Dell and Intel.

CUI’s power division, V-Infinity, continues to

focus on technologies that support the green

initiative and digital power is an area that

has great growth potential. “Digital power is

very intriguing to CUI and we intend on

investigating all options” said Matt McKenzie

CUI’s President. “Our focus is on develop-

ing solutions in growing technologies that

solve complicated needs with an emphasis

being on the ease of implementation.” The

digital power market segment is just entering

the adolescent stage according to the Dar-

nell Group and by 2010 will pass 5 billion

units in cumulative sales.

As technology moves towards greener appli-

cations, communication and intelligence with

data becomes essential in the successful

implementation of these technologies. As a

potential adopter of PMBus, CUI feels that it

is essential that they are part of the forum

that manages this standard. Matt McKenzie

continued, “CUI products were sold to nearly

50,000 customers in 2008 across every mar-

ket segment and the majority of those cus-

tomers have problems that digital power

could solve if it was easy to implement. We

are excited about the possibilities.”

www.cui.com

New Member of PMBus

Micrel Inc.

announced that

Chris Dingley,

Director of

Micrel’s Global

Account and

Western Sales

Territory, has

been promoted to

the position of

Vice President,

Worldwide Sales. In his new role, Mr. Ding-

ley has responsibility for the Company’s

global sales efforts.

Mr. Christopher Dingley has more than 22

years experience in the semiconductor

industry. He joined the Company in June

1997 as Director of Global Distribution and

was then named Director of Global Distribu-

tion and EMS. He was then promoted to

position of Director of Micrel’s Western Sales

Territory including Global Account responsi-

bility for Cisco. Prior to joining Micrel, Mr.

Dingley was Distribution Manager for Win-

bond North America. Before this, Mr. Ding-

ley held the positions of Area Sales Manager

and Distribution Sales Manager with General

Instrument. He attended Arizona State Uni-

versity where he studied Marketing and

Electrical Engineering Technology.

www.micrel.com

Chris Dingley VP, Worldwide Sales

© 2009 Cirrus Logic, Inc. All rights reserved. Cirrus Logic, Cirrus, the Cirrus Logic logo designs, Apex Precision Power, Apex and the Apex Precision Power logo

designs are trademarks of Cirrus Logic, Inc. All other brands and product names may be trademarks or service marks of their respective owners. BPS10-2009

innovationinnovation Product Innovation from Cirrus Logic

N O RT H A M E R I CA+1 800-625-4084

A S I A PA C I F I C+852 2376-0801

J A PA N+81 (3) 5226-7757

E U R O P E / U K+44 (0) 1628-891-300

For product selection assistance or technical support with Apex Precision Power® products email apex.support@cirrus.com.

FC MODULAR 42-PIN DIP

Open Frame Product Technology

(actual footprint 65.1mm X 42.5mm)

DP 12-PIN POWER SIP

(actual footprint 30.99mm X 20.17mm)

Model SlewRate

OutputCurrent

Supply VoltageOperation

PA107DP 3000 V/μs1.5 A continuous

5 A Peak

40 V to 200 V

Dual Supply

MP103FC 180 V/μsUp To

15 A PEAK

30 V to 200 V

Dual Supply

The PA107DP and MP103FC are the newest additions to the Apex Precision Power® family of

high speed, high voltage power amplifiers from Cirrus Logic. The PA107DP is housed in a very

small Power SIP measuring less than two inches square. The device targets medical ultrasonic

and imaging applications by providing up to 3000 V/μs on voltage supplies up to 200 V. For ap-

plications requiring lower speeds, but multiple drivers, the MP103FC is a dual channel amplifier

with a high power bandwidth of 230 kHz,

or a 180 V/μs slew rate. The open frame

form factor of the MP103FC is ideal for

high speed assembly and provides a low

per unit cost in comparison with many

in-house discrete designs.

Small Package Drives Big Speed For Piezo Transducers In Ultrasonic Medical Applications

DOWNLOAD A COPY OF THECIRRUS LOGIC V15 APEX PRECISIONPOWER® PRODUCT DATA BOOK ATWWW.CIRRUS.COM/107BPS

L E A R N M O R E AT

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8 Bodo´s Power Systems® October 2009 www.bodospower.com

N E W S

The most important meeting place for the

electric automation sector, SPS/IPC/DRI-

VES, will take place from 24 – 26 November

2009 in Nuremberg. The exhibition covers

the whole electric automation market and

focuses on the specific requirements of

users. This was affirmed in a recent survey

of the members of the Executive Committee

and the technical faculties of ZVEI (German

Electrical and Electronic Manufacturers´

Association) which showed that there is nei-

ther the need nor the desire to change the

concept, the structure, the modus operandi

or the location of the event.

In this the 20th year of the event, more than

1,300 companies are expected to exhibit at

SPS/IPC/DRIVES. They will fill eleven exhi-

bition halls with the complete array of com-

ponents and systems in the electric automa-

tion sector which will be on show to a trade

audience. Nearly 300 exhibitors from outside

Germany will be participating.

The main focus on the exhibition stands is

the dialogue with users. For the exhibitors,

there is the chance to persuade the high cal-

ibre trade audience (two-thirds work in

design and development, production or man-

agement) of the merits of their products. And

visitors can access a high volume of infor-

mation and guidance in their search for the

best solution to their automation problem.

As a result of the high visitor numbers the

SPS/IPC/DRIVES Exhibitors’ Advisory Board

has decided to extend the opening times this

year. Thus on Tuesday, the first day of the

exhibition, the halls will stay open until 19:00

hrs, which will allow more time for detailed

discussions between the users and the

exhibitors. This will also relieve the pressure

on the Wednesday which is traditionally very

busy. The event will continue to take place

over three days, from Tuesday to Thursday.

Important topics in the spotlight at

SPS/IPC/DRIVES 2009

The main topics at this year’s SPS/IPC/DRI-

VES, “Safety and Security”, “Energy Efficien-

cy” and “Industrial Identification” will be

addressed at the forums in the eleven exhi-

bition halls and at the simultaneous confer-

ence. The importance of these topics for

today’s electric automation sector will be

reflected in the products and services being

offered on the exhibition stands.

www.mesago.com/sps

SPS/IPC/DRIVES 2009 Extended Opening Hours on the First Day

American Superconductor announced that it

has received its second order for a D-VAR

system to meet dynamic reactive compensa-

tion requirements for the Chinese power

grid. Beijing-based China National Machin-

ery Industry Complete Engineering Corpora-

tion (CMCEC) will deploy the D-VAR system

to meet local grid interconnection require-

ments for Phase I of the Guanting Wind

Farm, located in the Beijing area. AMSC

expects to deliver the D-VAR system to

CMCEC by the end of calendar year 2009.

AMSC customers utilize D-VAR solutions to

provide voltage regulation and power factor

correction, along with post-contingency

assistance to stabilize voltage, relieve power

grid congestion, improve electrical efficiency,

and prevent blackouts in power grids. D-

VAR reactive compensation systems are

classified as Static Compensators, or “STAT-

COMs,” a member of the FACTS (Flexible

AC-Transmission System) family of power

electronic solutions for alternating current

(AC) power grids. These Smart Grid solu-

tions are able to detect and instantaneously

compensate for voltage disturbances by

dynamically injecting leading or lagging reac-

tive power into the power grid. AMSC has

received orders for over 70 STATCOM

power grid solutions worldwide, more than

all other manufacturers combined. The com-

pany’s STATCOM customers include more

than 20 electric utilities and over 45 wind

farms.

www.amsc.com

Dynamic Reactive Compensation Solution to Meet Grid Interconnection

Murata Power

Solutions has

appointed Chris

Viola as Vice

President, World-

wide Sales &

Marketing. He

moves to the new

role from his pre-

vious position as

Vice President of

Supply Chain Management that he has held

since joining the company in 2006.

As Vice President, Worldwide Sales & Mar-

keting Chris will have overall responsibility

for the global sales channel, product market-

ing teams and marketing communications.

Prior to joining Murata Power Solutions,

Chris held senior positions with both Celesti-

ca and Lucent. Chris is based at Murata

Power Solutions’ Mansfield, MA facility in

North America.

Commenting on the new appointment, Chris

Conlin, CEO, Murata Power Solutions, said:

“Murata Power Solutions has great confi-

dence in Chris’s ability to lead the sales

channel and marketing teams to new levels

of success. His experience, product knowl-

edge, enthusiasm and business acumen

strongly position us for sustainable future

growth.”

www.murata-ps.com

Chris Viola appointed VP, Worldwide Sales & Marketing

Texas Instruments introduced a 15-W stereo,

true filter-free, analog-input, Class-D audio

amplifier. The device’s advanced electro-

magnetic interference (EMI) suppression

technology eliminates the need for costly

inductor-based output filters, reducing bill of

materials (BOM) cost by as much as 50 per-

cent. The TPA3110D2’s SpeakerGuard pro-

tection circuitry protects speakers from dam-

age, helping to reduce end equipment cus-

tomer returns and associated support costs.

The device also features enhanced perform-

ance, making the TPA3110D2 an excellent

choice for consumer audio applications,

including HDTVs, media docking stations,

digital radios and sound bars. For product

details and to order evaluation modules and

samples see: www.ti.com/tpa3110d2-preu.

www.ti.com

Class-D Amplifiers Feature True Filter-Free Operation

10 Bodo´s Power Systems® October 2009 www.bodospower.com

Texas Instruments introduced the smallest 2.25-MHz DC/DC convert-

er for USB-powered portable applications and wireless modems. The

TPS62750 is a high-performance, 92 percent power-efficient, syn-

chronous step-down converter, which can provide up to 1-A typical

input current. The device supports an input voltage from 2.9 V to 6 V,

allowing it to support batteries with an extended voltage range and

USB-compliant power requirements.

The Features are:

• Efficiency > 90% at Nominal Operating Conditions

• Programmable Average Input Current Limits for USB Applications

o 50mA to 300mA for Low Current Limit Range

o 300mA to 1.3A for High Current Limit Range

±10% Current Accuracy

• Stable Output Voltage for Load Transients to

Minimize Overshoot at Load Step Response

• Hot Plug and Reverse Current Protection

• Automatic PFM/PWM Mode transition

• VIN Range From 2.9V to 6V

• Adjustable VOUT From 0.8V to 0.85×VIN

• Softstart for Inrush Current Prevention

• 2.25 MHz Fixed Frequency Operation

• Short Cicruit and Thermal Shutdown Protection

• Available in a 2.5 × 2.5 10 pin SON Package

• APPLICATIONS

o USB Wireless Modems

o Portable USB peripherals

o Handheld Computers

The TPS62750 device is a highly efficient synchronous step down

dc-dc converter optimized for USB powered portable applications. It

can provide up to 1300mA average input current and is ideal for

applications connected to a USB host.

With an input voltage range of 2.9 V to 6.0V, the device supports bat-

teries with extended voltage range and is ideal for powering USB

applications where USB compliance is required.

The TPS62750 operates at 2.25-MHz fixed switching frequency and

enters Power Save Mode operation at light load currents to maintain

high efficiency over the entire load current range. Output discharge

allows the load to discharge in shutdown.

The 10% accurate average input current limit can be programmed

with an external resistor, allowing use in applications such as USB,

where the current drawn from the bus must be limited to 500mA.

The device has a dynamic AVERAGE INPUT CURRENT LIMIT

The average input current limit can be set to two different values by

external resistors. These limits can be dynamically switched by a

high/low signal at the enable pin. This has the added benefit that of

allowing a device first plugged into the USB port to enumerate at

100mA before switching over to the high power mode (500mA).

In addition to small size, the TPS62750 offers a high degree of per-

formance and efficiency. The device’s unique Power Save Mode

operates at light load currents over the entire load current range. In

addition, the converter can discharge during shutdown.

The TPS62750 is available in volume now from TI and its authorized

distributors in a 10-pin, 2.5 mm x 2.5 mm SON package. Suggested

resale pricing is $1.20 in 1,000-unit quantities. The TPS62750EVM-

413 evaluation module, samples and application notes are available.

Texas Instruments (NYSE: TXN) helps customers solve problems

and develop new electronics that make the world smarter, healthier,

safer, greener and more fun. A global semiconductor company, TI

innovates through design, sales and manufacturing operations in

more than 30 countries.

www.ti.com

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

2.25-MHz, 1-A DC/DC Converter for USB-Powered

Applications

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12 Bodo´s Power Systems® October 2009 www.bodospower.com

The concept of the

electric car is older

than the internal

combustion

engine, and over

the years there

have been numer-

ous attempts to

develop electric

vehicle technology.

However, it is only in recent years – thanks

in no small part to consumer environmental

concerns and legislation on vehicle emis-

sions – that we are seeing signs of a com-

mercially viable electric vehicle market.

For the same reasons, the market for hybrid

automobiles is also set to see significant

growth. However, estimates for such growth

vary widely, partly due to the fact that this is

an emerging market and partly because of

the various definitions that can be applied to

the hybrid concept. It may, for example,

include vehicles that feature a ‘start-stop’

function that switches off the combustion

engine when a vehicle is stationary (for

instance at traffic lights). Then there are

‘micro-hybrids’, which add an energy recov-

ery braking system to start-stop capabilities,

or so-called ‘mild hybrids’ that incorporate a

medium-power electric motor to assist the

combustion engine and improve efficiency.

Finally we have the full hybrids that can

drive small distances using only electric

motors.

The good news for the electronics industry is

that electric vehicles (EVs) and Hybrid Elec-

tric Vehicles (HEVs) of all types require

much higher levels of silicon content than

the majority of vehicles based on the com-

bustion engine. In fact, semiconductors and

complementary electronic technologies –

and in particular those technologies that can

deliver cost-effective and efficient power

management systems - are critical to the

successful commercialisation of EV and

HEV designs.

Take, for example, the start-stop capability

mentioned above. This has an attractive cost

advantage in that it runs on a standard 12V

powernet, eliminating the need for both high-

er voltage schemes and batteries for energy

storage. The challenge, however, comes

from the fact that a powerful starter-alterna-

tor motor typically operating at up to 6kW is

required for the frequent engine cranking

cycles. Such an application requires very

rugged MOSFETs that combine the ability to

withstand junction temperatures as high as

200°C with very high avalanche capabilities.

In addition, providing the power for re-start-

ing the engine without any perceptible dis-

ruption to other vehicle functions requires

very efficient DC/DC converters that can

buffer the power demand during engine

start. These, in turn, create a demand for

fast semiconductor switching components

that feature very low EMI ratings.

EVs and HEVs that combine batteries,

regenerative braking systems and combus-

tion energy technologies and that work with

high voltage powernets have even more

requirements for advanced power manage-

ment silicon. These include high-power

switch, driver and control ICs capable of

handling voltages anywhere between 600V

and 1200V. Indeed, the biggest challenge for

automotive designers who are used to living

in a ‘12V world’ is how to implement systems

that address the very high voltages required

for EVs and HEVs.

Fortunately, semiconductor companies are

rising to the challenge and there is a growing

range of automotive-certified silicon devices

and integrated ASSPs available to designers

of EV and HEV applications. International

Rectifier, for instance, expects to release

over 200 new products for the automotive

sector within the coming 12 months. These

include highly efficient power devices such

as IGBTs and MOSFETs and novel, rugged

driver ICs with enhanced safety features.

Indeed there is a particularly strong focus on

protection functionality – the latest motor

driver ICs now incorporate functionality that

protects both the device and the associated

electronics without the need for microcon-

troller intervention in the case of catastrophic

failure or conditions such as short circuit of

the HEV traction motors. It is also worth not-

ing that International Rectifier’s power semi-

conductors were the first to offer guaranteed

safe operating areas for negative voltage

spike immunity – a common problem when

switching high currents with the high voltage

IGBTs employed in HEV inverters.

Semiconductor packaging developments are

also important in helping automotive engi-

neers to meet key design criteria when

developing EVs and HEVs. AEC-qualified

versions of technologies such as DirectFET,

for example, with its double-sided cooling

capabilities allow automotive engineers to

realise drastic space reductions in power-

hungry and high-speed switching applica-

tions such HEV DC/DC converters, while

techniques that eliminate bond wires

between package and die significantly

increase overall reliability.

At the same time, ongoing advances in sili-

con current densities reduce the number of

devices that need to be connected in parallel

in order to handle the high currents required

by EV and HEV designs. This, again, saves

space and improves reliability, while offering

additional benefits to engineers tasked with

developing their own control units and power

modules using bare die components.

Finally, while high power motor drives are

the most obvious opportunities for new and

emerging silicon devices, other opportunities

for semiconductor content in EVs and HEVs

should not be underestimated. In line with

their more environmentally friendly creden-

tials EVs and HEVs also demand ever

greater efficiency in a wide variety of periph-

eral systems. From battery management to

the brushless AC motors deployed in air

conditioning compressors, electric power

steering, fuel and oil pumps and engine

cooling fans, more and more semiconduc-

tors are needed to optimise the efficiency

and reliability of EVs and HEVs and, thus,

realise their true potential for commercial

success.

www.irf.com

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

Semiconductors Hold Key toElectric and Hybrid Vehicles

By Dr. Henning Hauenstein, Vice President and General Manager, Automotive Products Business Unit, International Rectifier Corp

Power Density – Next Level of Energy EfficiencySolutions for Energy Efficient Power Conversion Applications

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14 Bodo´s Power Systems® October 2009 www.bodospower.com

M A R K E T

ELECTRONICS INDUSTRY DIGESTBy Aubrey Dunford, Europartners

SEMICONDUCTORS

The Q2 2009 capacity

utilization of semicon-

ductor manufacturing

plants worldwide grew to

76.7 percent from 55.6

percent in Q1 2009, so

SICAS. Actual wafer-

starts grew sequentially

by 33 percent to 1.614 million per week in 8

inch equivalent wafers, but are still 24.4 per-

cent lower than those in Q2 2008.

The top 20 semiconductor companies, in

total, registered a Q2 09/Q1 09 sales

increase of 21 percent to $ 36.47 billion, so

IC Insights. This was a 37-point swing com-

pared to the Q1 09/Q4 08 results when

these same top 20 suppliers endured a

sales drop of 16 percent!

NEC Electronics, Renesas Technology,

NEC, Hitachi, and Mitsubishi have decided

to postpone the conclusion of a definitive

agreement to integrate business operations

at NEC Electronics and Renesas until the

end of September.

TSMC and UMC announced separately that

they will invest respectively $ 50 M ans $ 46

M in solar and LED markets.

Intersil will acquire Quellan, a supplier in the

design of analog signal processing ICs.

Intersil and Tower Semiconductor, a special-

ty foundry, will also work together to develop

a power management specialty process

technology platform. Intersil will utilize the

platform to manufacture its power ICs in

Tower’s state-of-the-art 200mm facility in

Migdal Ha’emek, Israel.

Avago Technologies, a global supplier of

analog semiconductor devices for communi-

cations, industrial and consumer applica-

tions, raised $ 648 M in the second biggest

IPO in US this year.

North America-based manufacturers of semi-

conductor equipment posted $ 569.7 M in

orders in July 2009 and a book-to-bill ratio of

1.06, so SEMI. The increases in both book-

ings and billings reported by North American

equipment manufacturers boosted the book-

to-bill ratio above parity for the first time

since January, 2007.

Total silicon wafer area shipments were

1,686 million square inches during the most

recent quarter, a 79 percent increase from

the 940 million square inches shipped during

the previous quarter so SEMI.

Wacker Chemie intends to concentrate sili-

con wafer production at lead sites. In the

300 mm wafer segment, the Burghausen site

is expected to become the focus of R&D-

related tasks, with production being pooled

at Freiberg and Singapore.

OPTOELECTRONICS

Large-area TFT LCD shipments grow by 42

percent Q/Q and 10 percent Y/Y in Q209 to

a record 130 million units, so DisplaySearch.

PASSIVE COMPONENTS

The connector industry achieved worldwide

sales of $ 8.069 billion in Q209, up 9.2 per-

cent from Q109, so Bishop & Associates.

Orders increased a healthy 17 percent. The

U.S., Japan, and Asia appear to have

reached the bottom. China is starting to

grow, and Europe will bottom in Q3.

OTHER COMPONENTS

The electronic design automation (EDA)

industry revenue for Q1 2009 declined 10.7

percent to $ 1192.1 M, compared to $

1334.2 M in Q1 2008, so the EDA Consor-

tium. The four-quarter moving average

declined 11.3 percent. Europe, the Middle

East, and Africa (EMEA) revenue was down

15.9 percent in Q109 compared to Q108.

The four-quarter moving average for West-

ern Europe was down 7.5 percent.

Germany1, a special purpose acquisition

company, has signed an agreement to

acquire AEG Power Solutions for cash and

shares assuming an enterprise value of €

532 M.

With 1,600 employees across 16 countries,

AEG PS provides precision, mission critical,

highly engineered power electronics solu-

tions for industrial, renewable and infrastruc-

ture applications. In 2008, AEG PS generat-

ed revenues of € 343 M and EBIT of € 56 M.

MEMS microphone pioneer Akustica has

been acquired by Bosch. Terms of the

agreement will not be disclosed. To date

Akustica has sold over 5 million micro-

phones. Bosch has also signed agreements

relating to the purchase of 39.43 percent of

the shares in Aleo Solar for € 46 M. In 2008,

Aleo generated sales of roughly € 360 M,

and employed some 800 associates. Bosch

also intends to acquire more than 60 percent

of the shares in Johanna Solar Technology.

Johanna employs 125 associates.

The Swiss group LEM has acquired the

Danish company Danfysik ACP for an undis-

closed amount. Danfysik ACP produces pre-

cision current transducers and had a

turnover of CHF 7.6 M in 2008.

Johnson Controls-Saft has been awarded a

$ 299 M US grant to build domestic manu-

facturing capacity for advanced batteries for

hybrid and electric vehicles. This award rep-

resents approximately half of the company's

total planned investment of $ 600 M.

Ener1 will take the lead among a group of

investors that plans to inject $ 47 M of equity

funding into Think Global, the Norwegian

electric vehicle producer. Ener1 is the parent

company of EnerDel, a US manufacturer of

lithiumion automotive battery systems. Ener1

will hold approximately a 31-percent stake in

the company.

A £ 20 M expansion of the Printable Elec-

tronics Technology Centre (PETEC) in North

East England was announced in July. In the

next four years it is estimated that this

investment will stimulate the creation of up

to 250 jobs in the North East and up to

1,500 jobs nationally..

DISTRIBUTION

Total European distribution bookings in the

second quarter of 2009 declined by 7 per-

cent when compared to the previous quarter

and declined by 31 percent compared to the

same period last year, so the International

Distribution of Electronics Association

(IDEA).

This is the comprehensive power related

extract from the «Electronics Industry

Digest», the successor of The Lennox

Report. For a full subscription of the report

contact: eid@europartners.eu.com or

by fax 44/1494 563503.

www.europartners.eu.com

16 Bodo´s Power Systems® October 2009 www.bodospower.com

Depending on what you read, the overall telecommunications market

is either on solid ground or has a tough road ahead. Opinions differ

as to where growth will take place. For makers of communications

power systems, the questions are spread over a number of different

segments, from customer premises equipment, to wireless, to central

offices, to emerging data communications technologies.

The Economist’s yearly industry assessment for telecoms predicts

that emerging economies will still invest heavily in network infrastruc-

ture, while recession-hit economies will delay upgrades. Falling rev-

enue will hit the big telecom companies in slower-growth economies,

while cash-rich telecom groups in emerging markets will be “increas-

ingly well-placed to expand into Europe or the US.”

On the optimistic side, Infonetics projects a 2% downturn in world-

wide carrier capital expenditures in 2009, followed by a flat 2010 and

a slow return to growth in 2011. On the other hand, UBS thinks capi-

tal expenditures could drop 10% to 20% in 2009. Most service

providers have clean balance sheets, so they are entering the global

crisis on solid financial ground. They went through a correction when

the Internet/telecom bubble burst several years ago, although the

current recession could further challenge them.

The long-term outlook for wireless applications is actually quite good.

Although general spending will go down in 2009, when they do make

purchases, large enterprises will spend more on wireless infrastruc-

ture than on wired, according to Vanson Bourne. In Europe, 54% of

IT directors had spent a greater portion of their budget on wireless

rather than wired equipment. Part of the reason is that the actual cost

of a wireless network is between one-fifth to one-tenth the cost of

installing a wired network.

Insight Research predicts that wireless revenues will jump from 60%

of all telecommunications services in 2008 to 72% in 2013, which

amounts to a 14.4% compound annual growth rate. The Asia-Pacific

region will experience the highest growth rate in the next five years,

at nearly 16%, led by China and India. The telecom sector in Latin

America and the Caribbean will grow by 12%, fueled by emerging

economies and the expansion of the middle class. Insight Research

expects global telecommunications revenue to increase from roughly

$1.7 trillion in 2008 to more than $2.7 trillion in 2013.

Another factor affecting revenue is that regulators in some countries

are actively pushing the sharing of build-out and operation of third-

generation (3G) radio networks. Cellular operators are under pres-

sure to reduce costs, and network features have become less impor-

tant in differentiating services than software and brand. This could

have an impact on the sale of power systems used in these net-

works. This could push companies like Orange, Bouygues Telecom

and the Vivendi-Vodafone joint venture SFR to follow in the footsteps

of the UK’s cellcos, as well as those in non-European countries such

as India, where the government recently allowed carriers to share

active as well as passive infrastructure.

In August, 2009, an investment of €18 million (about US$25 million)

was given by the European Commission (EU) for research into

fourth-generation (4G) wireless technology, which is expected to

boost the progression of 3G long-term evolution (LTE) technology, as

well. 3G LTE has already benefited from EU funding over the last five

years and is just beginning to bring “leading-edge” mobile benefits for

use by Europeans. 3G LTE mobile trials are underway in UK, Swe-

den, Spain, Norway, Germany and Finland, with other countries in the

pipeline. 3G mobile operators are forecast to spend around €6 million

(US$8.6 million) on 3G LTE equipment over the next four years.

Although the major European operators like Orange, T-Mobile and

Vodafone are sure they will move to LTE, they are not likely to deploy

it for at least two years, due to the global economic downturn. In the

near-term, an “interim” technology could be 3G HSPA+, a wireless

broadband protocol. Component makers are not holding back, how-

ever. LTE-capable chipsets are expected to be available by the end

of 2009. Ericsson already claims to be currently installing an LTE-

compliant commercial network. Some chip vendors are supporting

both HSPA+ and LTE.

The transition to fiber-to-the-home (FTTH) is “well underway,” with

the number of households with fiber-optic network connections grow-

ing by nearly 43% worldwide in 2008, according to a report from

Heavy Reading. This growth will continue at rates above 30% a year

through 2012 and penetrate countries such as Denmark, France,

Hong Kong, Japan, Korea, Sweden, Taiwan and the US. Over the

next five years, most other developed countries will join this list, and

fiber will also have a significant impact in relatively less-developed

telecom markets, including India, Russia and the Middle East.

Europe will see rollout dominated by municipal and utility builders,

most of which are using active Ethernet. Passive optical networking

will drive more traffic onto the network backbone and will provide

increased opportunities for manufacturers of power systems and dc-

dc converters.

The Broadband-over-Powerline (BPL) market is still considered to be

in the very early stages of development and commercialization. The

promise of BPL is perhaps greatest in its potential to extend the

broadband network reach to the approximately two billion people

across the world that are still unable to connect to modern voice and

data services, and remain without access to modern high-speed

telecommunications services. The further development of BPL in

these areas would reduce opportunities to the makers of power sys-

tems used in the traditional broadband market. In addition, many

industry observers see BPL as eventually replacing other forms of

remote asset management, including supervisory control and data

acquisition (SCADA), teleprotection and the use of narrow bandwidth

forms of powerline carrier communications (PLC).

Current Group, a smart-grid provider, says that “some telecommuni-

cations companies have expressed interest in its BPL technology,”

but more so in Europe than in the US. GSM/GPRS/CDMA modems

are often used for remote metering. Embedded cellular modems

often have a simple serial interface and use the standard AT com-

mand set for configuring and making phone calls. Companies such

as Motorola, Sierra Wireless and Falcom manufacture GSM/GPRS

and CDMA-based modems for embedded systems.

Also, if the consumer voice-over-IP (VoIP) market is representative of

the future telecom industry, Europe could be a big winner. In Europe,

regulatory policies force incumbent operators to manage their net-

M A R K E T

New Market Drivers for TelecomBy Linnea Brush, Senior Research Analyst, Darnell Group

work infrastructure separately from their retail services. Next-genera-

tion network facilities are available to all competitors on an equal

basis. European incumbent operators are losing fixed-line sub-

scribers to VoIP, with a large build-out of next-generation networks.

Finally, energy efficiency is a major feature driving power supply

sales across all industries and applications. Telecommunications

power, by definition, is dc power, which is already highly efficient.

Carriers are looking for lower utility bills, just like data center opera-

tors, however. Regulatory actions could have an impact on rectifier

design, particularly for broadband applications.

In 2006, the European Commission (EC) issued the Code of Conduct

(CoC) on Energy Consumption of Broadband Equipment. Tier 1

entered into force in January, 2007; Tier 2 started in January, 2008

and was valid for one year. The CoC is a voluntary base initiative

with the aim of targeting “reduced energy consumption of broadband

communication equipment without hampering the fast technological

developments and the service provided.”

One of the aims for both network and customer equipment is to

require power reduction and adoption of power management (low

power modes L2/L3) for new ADSL2+/VDSL2 systems. The require-

ments on power reduction push for specific study and development of

energy efficient equipment, while the implementation of power man-

agement would allow benefits from time periods when data traffic is

limited or absent.

Telecom Italia Group is actively involved in this initiative, and in a

presentation at Intelec, 2007, they indicated that the power targets

are challenging. The 2008 goal was “a complete redesign of digital

subscriber line (xDSL) chips and systems, and the development of

power management mechanisms will require analysis and proposals

in conjunction with standardization bodies (ITU-T/ETSI).” In fact, a

proposal to start standardization activities on power consumption

reduction of DSL equipment has been presented with wide support

from operators and accepted (ETSI TM6 and ITU-T SG15).

Network equipment covered under the CoC includes DSL ports, com-

bined ports, ISDN terminators at customer premises, WiMAX base

stations, powerline communications and cable service provider equip-

ment and optical network terminals. Tier 1 and Tier 2 refer to the

maximum power consumption targets (power measured on the

230Vac input).

Intamac Systems, a UK-based home system management company,

already sees the telecom-home energy combination as a “lucrative”

one. They have deployed about 600,000 devices in British homes,

most installed in partnership with utilities. But one of their partners

has devices that are being installed by telecommunications compa-

nies. This program is new and being tested, but commercial availabil-

ity of the system is expected “soon.”

Intamac is also working with BT Group to add “environmental man-

agement” capabilities to its home wireless gateways. They will be

partnering with a US-based telecommunications provider to bring Zig-

Bee-enabled home energy management devices, including smart

thermostats, to the American market. Although most North American

utilities are opting to build and own their own communications net-

work for smart meter deployments, many in Europe are turning to

cellular networks instead.

Global Communications Power: A White Paper on Recent Market and

Forecast Trends

http://www.darnell.com/store/products_info.php?products_id=97

www.powerpulse.net

www.bodospower.com

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18 Bodo´s Power Systems® October 2009 www.bodospower.com

Concept of the ISOPLUS™ family

GWM /GMM package is part of the IXYS developed ISOPLUS™ fam-

ily. It features isolated packages that are footprint compatible to stan-

dard housings like TO220, TO247 etc. However in the ISOPLUS™

concept the dice are soldered on a DCB instead on a copper base. A

DCB (direct copper bonded) is a “sandwich” of a ceramic with copper

layer on both sides. After soldering and wire bonding those ceramic

plates are transfer moulded similar to standard packages, see Figure

1. The Cu layer of the DCB can be structured by etching (just like a

PCB) allowing realization of complex circuitries by multi chip packag-

ing. Buck, Boost, Phase legs, 6-packs, and 3-phase input rectifiers

are some of the configurations which are already available in ISO-

PLUS™ packages.

The usage of a DCB as a base carrier for the dice gives the cus-

tomer the following advantages:

(A) isolation from the heat sink (up to 2.5 kV without isolating foil)

(B) higher integration

(C) multi chip solution, complex circuit topologies

(D) reduction of stray inductance

(E) low coupling capacity from chip to heat sink

(F) excellent heat transfer (low thermal impedance for isolation)

(G) very high temperature and power cycling capability

The ISOPLUS-DIL™ package is a dual in line version with max 12

pins on both sides (developed for voltages up to 150 V Products,

see Figure 8) with a package body of 37.5 x 25 mm² in size (Figure

2). The thickness of DCB’s ceramic is 0.38 mm with Cu layer 0.1 mm

thick.

GWM devices offer a 6-pack configuration with a single DC+ and DC-

bus bar pin connection whereas GMM parts makes use of 3 half

bridges identical but electrically separated

(Figure 3).

Both variants are available with SMD pins

allowing the usage in PCB reflow production

process eliminating the need of selective pin

soldering. The backside of the package is

mounted on the heat sink by the use of std

inferface materials like heat transfer paste

or phase change foils.

GMM – a further step to higher reliability

All package constructions suffer from the difference in the expansion

coefficients of the used materials which are Si (die), solder, copper

base and wire bonds (Al). Regardless whether an external tempera-

ture change – variation of heat sink or ambient temperature – or

internally by power losses they result in mechanical stress because

of different length variations of the materials, see Figure 4.

C O V E R S T O R Y

ISOPLUS-DIL™ SeriesDesigned for Highest Reliability

The GWM series in ISOPLUS-DIL™ package (Dual-In-Line) has been developed to production standard. It is a transfer moulded module which combines the advantage of arobust package (like discretes) with the functionality of a module with isolation from heat

sink and complexity in the circuit. The GMM series is an improved version and coversmarket demands for SMD mountability and highest reliability and is equipped with highly

efficient fast switching TrenchMOSFETs.

By Andreas Laschek-Enders, IXYS Semiconductor GmbH, Germany

Figure 1: Cross section of an ISOPLUS™ package

Figure 2: ISOPLUS-DIL™ package - GWM and GMM layout

Figure 3: GWM and GMM circuit diagram

19www.bodospower.com October 2009 Bodo´s Power Systems®

Small variations are mainly elastic, large ones especially at the low

end of package specified temperature tend to be plastic. Temperature

cycling between min and max of package operating temperature is

an extreme stress resulting in failure modes including packaging or

die cracks, damages of solder connections either die or pins and wire

bonds lift off. Damages of the solder connection between die and

base firstly increase the thermal impedance. Under electric loads this

results in a further temperature rise and therefore to larger cracks or

voids of the solder layer. Finally this thermal run away causes the

device to fail.

ISOPLUS™ package construction principally reduces this failure

mechanism because DCB is better matched to Silicon than Copper,

see Figure 4. GWM and GMM packages withstand more than 1000

temperature cycles from – 55 °C up to +150 °C.

Power cycling induces the stress by power loss variations in the die.

Especially at low voltage designs these losses are correlated with

high current loads. For example: A 25 mm² 1200V IGBT die can han-

dle about 30 A but a 40 V Trench MOSFET die of same size approxi-

mately 220 A. Typically the top contact of the die is a wire bond con-

nection. The max number of bonds is limited by die size and current

density in low voltage designs is much higher than in high voltage.

Therefore bond power losses gain importance. Current density of

bonds can ramp up to more than 650 A/mm² making bond failures

more likely. For an example the power losses on a 8 mm long bond

wire for a 200 A current pulse in a TrenchMOS with 4 bonds is ~6.2

W (per wire). Usage of the max possible number and reduction of the

length of the bonds is a way to achieve high power cycling capability.

As the 3 half bridges of the GMM can be connected like a 6-pack

GWM and GMM offer the same functionality. But the split into 3 half

bridges leads to a further improvement of the internal layout with

shorter bond connections. This is shown in Figure 5.

Figure 4: Expansion coefficients

Expansion Length variation �lMaterial Coefficient for l=10mm & �T=100°C

[10-6 1/K] [ μm ]Silicon 2.5 2.5DCB 7.4 7.4

Copper 16.5 16.5Aluminum 23.0 23.0

Sn 26.7 26.7

ABB FranceCurrent & Voltage Sensors Departement

e-mail: sensors.sales@fr.abb.com

Shared experience

creates a shared

success?

Certainly.

The ES range has become our bestseller; this is due to an optimisation of its design using our

shared experience with our customers.

These upgrades allow us to offer the most cost effective sensor in high current measurement.

As drives become more and more compact, we also have enhanced the ESM range in terms of

magnetic immunity and dynamic response.

Thanks to these improvements, we are able to offer our clearest signal increasing the

performance of your equipment. www.abb.com

Figure 5: DCB of GWM and GMM package

20 Bodo´s Power Systems® October 2009 www.bodospower.com

The result is an approximately 3 times high-

er power cycling capability of the GMM at ΔT

= 100 °C with Id = 100 A (!)

GMM – reduction of stray inductance

In order to allow fast switching, one of the

tasks is to reduce package stray inductance.

As the reduction of the current paths length

is limited because of die and package

dimensions another approach is to reduce

the active area in the current loop especially

in those paths with non continuous current.

For a half bridge or 6-pack configuration this

is mainly an issue for the DC bus current,

see Figure 6.

The switching duty cycle adds only a ripple

to the output current (Figure 6: IL) but the

current to the bus (Fig 6: IDC+ ,IDC-) have

“ON”/”OFF” characteristic with high ΔI/Δt at

the edges. With the stray inductance Lstray

they introduce a voltage peak ΔU proportion-

al to L x ΔI/Δt. This may drive the device into

avalanche at the switching transient stress-

ing the device electrically. This is valid espe-

cially under high load currents at high supply

voltage.

As it is not a simple task to calculate the

stray inductance of modules one measure-

ment method is to apply a current pulse with

known ΔI/Δt. By measuring the voltage over-

shoot with a scope one can determine Lstray

according to the formula

Lstray = ΔU / ΔI/Δt.

This test has been performed on GWM and

GMM on a “short circuit” sample (Figure 7).

Here the DCB has been built without die and

just the bonds only. ΔI/Δt test performed on

the the DC bus current loop clearly shows

that GMM layout reduces Lstray further:

GWM: Lstray = 15 nH

GMM: Lstray = 10.5 nH

With ΔI/Δt = 1000 A/μs the voltage margin

increases by 4.5 V which is of interest when

using TrenchMOSFETs with Vds of only 30

or 40 V.

The reduction of stray inductance is obvious

comparing the DCB layouts of GWM and

GMM, see Figure 5 and 7. The GWM DCB

has a bus bar structure inside the package

with the dice placed either side. This mini-

mizes the internal current loop area of the

bus bar but the half bridge at the end sees

the full bus bar length. Even more these dice

see also the switching activities of the other

half bridges. As the current in the bus struc-

ture is the sum of the currents of all 3 half

bridges this gives an additional overshoot

when all devices are

switched at the same

time.

In the GMM layout the 3

phase legs are separat-

ed with their own bus

connections and the lay-

out is optimised reduc-

ing the current loop area

further. This explains the

reduction in Lstray by

about 30%. Also the

internal DC coupling

between the half

bridges is eliminated.

GMM – distributed power pins

The bus pins of GWM are 4 mm wide and

they are able to handle the current of the 6-

pack but the current entry on the board

could be problematic. Although GMM’s

power pins have a width of only 1 mm exper-

iments have shown that under high load

conditions the PCB contact area stays cool-

er. In a design with a max current of ~210 A

for the 6-pack correlated to ~70A for every

phase leg of the GMM the contact area to

the PCB ran ~60°C cooler and the tempera-

ture was below the max allowed value for

the circuit board.

Another advantage of splitting up the 6-pack

into 3 identical half bridges is the optimized

Kelvin source contact. At all dies it comes

direct from the source without load current

sharing and is bonded directly to the pack-

age pin. This gives the designer the max

possible control of the die (Figure 5).

Conclusion

The GMM series is an improved ISOPLUS-

DIL™ package featuring very high power

and temperature cycling. The layout of 3

electrically isolated and optimized half

bridges and the use in SMD soldering pro-

duction process gives the design engineer a

perfectly suited device for drives used in

robotics, automotive or battery powered

application. The GMM will be available in 40

V through 150 V. Customer special solutions

with different topologies are possible.

www.ixys.com

C O V E R S T O R Y

Figure 8: Product table and status

Device VDSS V

ID25A

R DS(ON)typ m�

Status

GMM 3x180-004X2-SMD 40 180 1.9 engineeringGMM 3x160-0055X2-SMD 55 150 2.2 activeGMM 3x120-0075X2-SMD 75 110 4.0 activeGMM 3x100-01X1-SMD 100 90 7.5 engineeringGMM 3x60-015X1-SMD 150 60 17 engineering

Figure 7: Current paths in GWM and GMM “short circuit” sample for measuring Lstray

Figure 6: Current paths in a half bridge

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Improvements in the MOSFET designs allow the circuit designers to

utilize the improved device level performance. Increases in switching

frequency and other critical parameters allow the converter design to

operate more efficiently. In some cases this may allow circuit design

modifications that would not be possible without these improved

MOSFET designs.

In 2006, the OptiMOS™ 2 100 V MOSFET was introduced by Infi-

neon in response to these requirements [1]. It was the first power

MOSFET device, within this voltage range that was based on charge

compensation techniques. This resulted in a significant reduction of

the MOSFET on-resistance over traditional designs whilst retaining

excellent switching behavior.

The release of the OptiMOS 3 series improves the design further and

allows higher voltage devices to benefit from these technologies.

OptiMOS 3 devices not only have best in class performance in the

150 V to 250 V sector but combines this with several key parameters.

The new devices exhibit low gate-charge characteristics, high switch-

ing speeds and good avalanche ruggedness. These attributes make

them suitable for a wide variety of switch-mode power supply (SMPS)

applications. These include high-efficiency AC/DC SMPS and DC/DC

converters for telecommunication and server based applications,

Class-D amplifiers and motor-control driver applications.

Device Concept

The compensation principle for power MOSFETs was introduced in

1998 in commercially available products with the 600 V CoolMOS™

technology [2]. The basic principle behind the drastic RDS(on) x A

reduction compared to conventional power MOSFETs is the compen-

sation of n-drift region donors by acceptors located in p-columns as

depicted in Figure 1.

For lower breakdown voltages, trench field-plate MOSFETs are an

excellent alternative. The application of a field-plate clearly improves

the device’s performance. The device comprises of a deep trench

penetrating through most of the n-drift region. An insulated deep

source electrode, separated from the n-drift region by a thick oxide

layer, acts as a field-plate and provides mobile charges required to

balance the drift region donors under blocking conditions as it is

schematically shown in Figure 1. Standard MOS structures exhibit a

linearly decreasing vertical electric field having the maximum field-

strength at the body/drift region pn-junction. Such devices do not

show a lateral component of the electric field. In a field-plate device,

there is also a lateral component of the electric field and the space-

charge region expands mainly in lateral direction. Consequently, an

almost constant vertical field distribution is gained and the necessary

drift-region length for a given breakdown voltage is significantly

reduced. Simultaneously, the drift-region doping can be increased.

Both techniques also result in a major reduction in on-state resist-

ance.

Extending the Device Family towards Higher Blocking Capability

The development of a new, space-saving and efficient edge-termina-

tion structure allows the OptiMOS 3 family to extend the benefits of

this technology to devices up to 250 V [3].

The combination of the termination structure and charge compensa-

tion technologies results in exceptionally low RDS(on) and results in an

excellent figure-of-merit FOM = RDS(on) x QG. A comparison to the

next best competitor device currently available is given in Figure 2,

clearly indicating the benefits of these technologies in terms of

improved device performance. The culmination of these technological

advances is a device that offers superior solutions for a wide range of

system requirements. In high-current applications like motor-control,

lowest-ohmic devices in D²PAK and TO-220 minimize conduction

losses and reduce the number of paralleled devices in the system. In

fast switching applications, the very low gate-drain-charge QGD and

FOMGD = RDS(on) x QGD cuts down on the switching losses and

M O S F E T

22 Bodo´s Power Systems® October 2009 www.bodospower.com

Extending the OptiMOS™ 3Power MOSFET Family

Performance for an energy-efficient world

Today, developments within the power conversion sector are driven by customer requirements for energy saving and physically smaller designs. Continual development of converter topologies for AC/DC and DC/DC has resulted in improved efficiency atconverter level. Power MOSFETs are the core component of power converters in this

market sector and are fundamental in producing an efficient design.

By Dr. Ralf Siemieniec and Dr. Oliver Häberlen, Research & Development, and Juan Sanchez, Technical Marketing, Infineon Technologies

Figure 1: Compensation of drift region by p-doped columns (left) andby a field-plate (right)

improves the overall efficiency. Devices available in SuperSO8 pack-

ages are therefore the perfect choice for applications like DC/DC

converters or Class-D amplifiers. Furthermore, the very low on-resist-

ance RDS(on) often allows for a package shrink. TO-247 packages

can be replaced by TO-220, a D²PAK or TO-220 can often be

replaced by a SuperSO8. The net result is a very compact, space

saving solution, which delivers significantly better switching perform-

ance.

Another important issue is paralleling, especially in case of high-

current applications such as motor control. To meet the application

requirements it is often advantageous to make use of complete

power modules. This allows for improved heat management and

lower parasitics, both boosting the overall performance. Here, the

device count can be noteworthy reduced using the new device gen-

eration. Figure 3 gives an example of the switching waveforms of

large OptiMOS 3 150 V chips paralleled in a power module. Here, a

three-phase, full-bridge configuration was realized having eight chips

in parallel on one DCB substrate with again two DCB's in parallel.

Figure 3 shows the switching behavior of one phase leg at a supply

voltage of 80 V and a switched current of 500 A. The waveforms indi-

cate a smooth switching behavior with an acceptable overshoot volt-

age during the turn-off phase, no problems were observed.

Choosing the Right Power Package

With silicon technology moving rapidly forward the package becomes

an important part for low-voltage MOSFETs. Especially the package

inductance can play a major part in loss generation and for the over-

all device and application performance. Moreover, the on-resistance

of the latest device technologies has become remarkable low, thus

M O S F E T

23www.bodospower.com October 2009 Bodo´s Power Systems®

Figure 2: OptiMOS 3 150 V, 200 V and 250 V Benchmark in RDS(on)and FOM

Figure 3: Switching waveforms of paralleled OptiMOS 3 150 V chipsin a power module at a duty-cycle of 13%. Left: full pulse showingturn-on and turn-off (200A/div, 20V/div, 4μs). Right: detailed turn-offslope (200A/div, 20V/div, 80ns) [4]

driving the need for low ohmic packages to avoid a limitation of the

device by the package characteristics.

30 V technologies from most vendors today allow for MOSFET dies

in a TO-220 with a lower on-resistance than the package resistance.

Latest 60 V technologies on the market allow for devices with a pack-

age contribution of below 30% and even for 100 V technologies the

package can already account for more than 20%, given a package

resistance of 1 mOhm. Therefore, the package resistance clearly

limits the minimum on-resistance achievable. Additionally, a larger die

is required for a given on-resistance which also increases the gate

charge and thus slowing down the device switching.

Package contributions for devices with maximum die size for the

most common low-voltage MOSFET classes are shown in Figure 4.

To follow the route towards denser and more efficient power

converter designs, new package types, such as the SuperSO8, S3O8

or the DirectFET/CanPAK, are needed to replace the leaded SMD or

through-hole devices for low-voltage MOSFETs.

It is easily possible to estimate the losses due to package inductance

for the turn-off. As example, a buck-converter with an output current

of 30 A, operating at 250 kHz, generates 0.7 W of losses in a DPAK

design due to the total package inductance of 6 nH. With a low

inductive package like the SuperSO8, showing an inductance of just

0.5 nH, the losses drop below 0.1 W. The lower package inductance

also helps to avoid an unwanted turn-on of the MOSFET due to the

source pin inductance in case of fast transients.

Another package-related topic is heat-spreading which can be

improved by either using an improved standard package or by com-

pletely shifting to newer package types. As shown in Figure 5, the

use of a D²Pak with 7 pins instead of a standard D²PAK already

results in the avoidance of hot spots and a lower overall temperature.

More advantages are gained if SuperSO8 packages are used. Figure

6 gives the comparison between D²PAK-7pin devices and the same

amount of active silicon area packaged in SuperSO8 devices. Not

only is the temperature behavior improved and a smaller PCB area is

occupied, but the SuperSO8 packages also offer the chance to apply

topside cooling for further improvements.

Summary

With the actual release of its OptiMOS 3 technology in the voltage

classes 200 V and 250 V Infineon Technologies now covers the full

voltage range from 25 V to 250 V. With OptiMOS 3 being best-in-

class for every single voltage class with respect to static and dynamic

losses enables customers to deliver future power converters with

unprecedented efficiencies and power densities for a wide range of

topologies.

References

[1] R. Siemieniec, F. Hirler, A. Schlögl, M. Rösch, N. Soufi-Amlashi, J.

Ropohl and U. Hiller. A new and rugged 100V power MOSFET,

Proc. EPE-PEMC, 2006

[2] G. Deboy, M. März, J.-P. Stengl, H. Strack, J. Tihanyi and H.

Weber. A new generation of high voltage MOSFETs breaks the

limit line of silicon, Proc. IEDM, 683-685, 1998

[3] R. Siemieniec, F. Hirler and C. Geissler. Space-saving edge-termi-

nation structures for vertical charge compensation devices, Proc.

EPE, 2009

[4] R. Hoppersdietzel, R. Herzer: Measurement of the 80V three pase

MOSFET inverter system, Internal Report, Semikron Elektronik

GmbH, 2009

www.infineon.com/mosfets

M O S F E T

24 Bodo´s Power Systems® October 2009 www.bodospower.com

Figure 5: Thermal comparison between a D²PAK-7pin (left) and astandard D²PAK (right)

Figure 6: Thermal comparison between a D²PAK-7pin (left) andSuperSO8 devices (right) containing equivalent silicon area (right)

Figure 4: Package contribution to overall device resistance fordevices with maximum die size for several state-of-the-art technolo-gies

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26 Bodo´s Power Systems® October 2009 www.bodospower.com

Although various motor-control architectures and algorithms are

employed, depending on the application, final delivery of the calculat-

ed PWM signal to the motor is the responsibility of the trusty power

bridge circuit comprising four or six power MOSFETs. In automotive

motor control applications, the MOSFETs employed typically must

offer a number of attributes including small size, high current-han-

dling capability, high reliability, and the ability to withstand many thou-

sands of power cycles. Since MOSFET reliability is related to operat-

ing temperature, low-loss device design is imperative to minimise the

heating effects of continuous and pulse currents to which the device

may be exposed. Enhancements to device design are required at

both the package level and the silicon level, to satisfy these

demands.

At the package level optimising the characteristics of the device leads

and internal ohmic connections help to minimise I2R heating by

reducing electrical resistance. Low thermal resistance throughout the

leads, connections and overmold is also necessary, to help the

device dissipate generated heat as efficiently as possible. As far as

the silicon is concerned, lower on-resistance is a perennial goal for

device designers, to minimise I2R heating within the die. At the same

time, a low input capacitance, Ciss, is highly desirable for automotive

MOSFETs. This reduces turn-on energy and allows fast response to

control signals. For H-bridge use, the turn off behaviour is not an

issue. For three-phase BLDC, the dead time has to be controlled,

which means the turn off time has to be fast enough to prevent high-

and low- side MOSFETs from short circuit conditions.

Next-generation MOSFET silicon

Trench architecture is generally preferred among automotive MOS-

FETs, to achieve the desired characteristics of low RDS(ON), low

input capacitance, low gate charge and high current-handling capabil-

ity. Compared to trench devices, planar MOSFET technology has his-

torically delivered desirable characteristics such as high avalanche-

energy handling and latch-up immunity. More recently, trench tech-

nology has been able to approach the ruggedness of planar devices

with the advantages of lower on-resistance per unit area, delivering

clear advantages for automotive designers.

Trench MOSFETs for automotive applications continue to evolve, as

device developers target improvements such as smaller feature sizes

to further reduce RDS(ON), gate charge (Qg) and Ciss. In addition,

optimising trench width and depth allows higher channel density lead-

ing to higher current-carrying capability.

Toshiba U-MOS is a trench technology delivering low-loss and high

current-handling performance for automotive applications. The latest

U-MOS IV generation achieves a reduction in cell size that simultane-

ously enables lower RDS(ON) as well as lower Ciss. This has

enabled a significant improvement in the RDS(ON) x Ciss figure of

merit, translating into overall improvements in reliability, efficiency

and switching performance.

Package-Level Innovations

Historically, automotive MOSFETs have used conventional package

architectures and materials. To further improve reliability, which is

important given the high number of power MOSFETs built into mod-

ern vehicles, automotive MOSFET design is incorporating new and

higher-performing package features to help minimise the total device

on-resistance. Attention is focusing on optimal material selection and

dimensioning of leads, and on implementing low-loss interconnec-

tions between the leads and the die.

Improvements to the bondwires between the package leads and the

MOSFET die enable designers to improve reliability and deliver high-

er current-handling capability within a given package size. Some

technologies, for example, have implemented multiple bondwires per

terminal, thereby effectively increasing the cross-sectional area of the

interconnection. This has the effect of reducing the overall resistivity

of the interconnect, leading to reduced I2R heating.

Later developments at the lead-to-die interconnection have resulted

in new packages that feature a copper clamp in place of conventional

aluminium bondwires. The clamping mechanism maintains a reliable

mechanical connection capable of withstanding repeated power

cycling as well as exposure to shock and vibration. With a larger

cross-sectional area than a multi-bondwire interconnect, combined

with the higher electrical conductivity of the copper material, this

M O S F E T S

How Low Can You Go? Next-Generation Enhancements to Automotive MOSFETs

There is a steadily increasing quantity of electric motors in modern vehicles as electricactuation becomes the norm for numerous features ranging from air-conditioning controls

and seat and mirror adjusters to headlamp positioning and electric power steering.

By Dr Georges Tchouangue, Principal Engineer, Power Semiconductors, Toshiba Electronics Europe GmbH

Figure 1 – Package innovation

27www.bodospower.com October 2009 Bodo´s Power Systems®

design minimises I2R heating due to package losses. Replacing the

conventional bondwires with the copper clamp also delivers a reduc-

tion in package inductance, which makes a further contribution to

reducing heat generation as well as improving noise performance

and enabling faster device operation.

To take full advantage of this copper clamp technology, an enlarged

source terminal (Figure 1) creates a low-resistance pathway for cur-

rent entering the device, which translates into a lower source temper-

ature during operation. The enhanced channel structure also

improves the package power-dissipation capabilities. Figure 1 illus-

trates the improvement in package thermal resistance achieved

through combining the direct copper clamping structure and wide

source lead, highlighting around 20% reduction in channel-to-case

thermal resistance.

Combined Strength

Toshiba has combined the latest developments in U-MOS silicon with

the enhanced source termination and copper-based lead-to-die

clamping to develop its latest family of MOSFETs, which have been

optimised for automotive applications. These devices have high cur-

rent-handling capability, up to 150A, as well as maximum voltage of

75V(VDSS). The trench technology contributes to typical RDS(ON)

as low as 1.7m? and typical Ciss down to 4500pF. The robust pack-

age design featuring copper connections and the enlarged source

terminal has resulted in a predicted lifetime of high power cycles for

these devices.

In addition, the package thickness of 3.7mm is 21% thinner than

existing TO-220SM (also known as D2PAK) package technology.

This improves power dissipation by reducing the die-to-case thermal

resistance, and also provides extra opportunities for designers to

build smaller control modules that can be mounted nearby the motor

being driven. The package is qualified to AEC-Q101 at a channel

temperature of 175ºC, and TS16949 approval has also been

secured.

The improvements in performance throughout the package and the

die have enabled a valuable reduction in electrical losses combined

with improved heat dissipation. As a result, the average MOSFET

operating temperature is appreciably lower, as the comparison in fig-

ure 2 illustrates.

The graph shown compares the operating temperature as measured

at the drain, package surface and source lead of automotive trench

MOSFETs in the standard TO-220SM/D2PAK package and the TO-

220SM(W) WARP package. The wider terminal of the WARP pack-

age results in a significantly lower source temperature, and also influ-

ences the temperature measured at the MOSFET body. The temper-

ature curves demonstrate how the latest package and process tech-

nologies achieve almost a two-fold increase in current rating within

the industry-standard TO-220 footprint.

Conclusion

Environmental concerns are changing buyers’ expectations of cars

and the automotive industry. One constant, however, will be the

demand for continued improvement in performance, economy, com-

fort and value. The steadily increasing number of electrical systems

built into modern vehicles has delivered clear progress toward all of

these goals. Their success is partly due to improved motor types and

new control techniques, but continuous improvement in power-elec-

tronic technology is critical to meeting all of the demands placed on

modern vehicle electrical systems.

The latest generations of trench MOSFETs, incorporating improve-

ments to silicon and package construction, allow designers to deliver

extra functions, higher performance and increased reliability while

also achieving valuable size and cost savings.

www.toshiba.com

Figure 2: New technology delivers thermal resistance improvement

Figure 3: Reducing MOSFET source temperature

Increasing numbers of electronic appliances

and their interaction mean that suitable EMC

filters are more important today than ever

before. They are needed not only to observe

the EMC equipment limits (radiated interfer-

ence) but also to ensure reliable operation of

the equipment even under harsh conditions.

This also means protection from interference

coming from other equipment and from the

power line (perturbations). Reliable EMC

protection contributes significantly to assur-

ing machine availability, thus also providing

a useful sales argument for manufacturers of

systems, machines and installations.

The 2-line filters of the new SIFI® series

from EPCOS are now used successfully in

the most diverse applications. Thanks to

innovative materials, the dimensions of the

new SIFI series have been reduced still fur-

ther compared to their predecessor types

while retaining the same current capability. In

addition, constructional improvements have

also led to cost reductions.

Modular concept

EPCOS currently offers three new SIFI fami-

lies: SIFI-F (B84111F), SIFI-G (B84112G)

and SIFI-H (B84113H). They were devel-

oped as standard modular filters for single

phase systems (2-lines) with various attenu-

ation characteristics.

Fig. 1 is designed as a selection guide so

that EMC filters with correctly dimensioned

properties and thus the most cost-effective

solution can be found in a few steps.

The new SIFI families differ mainly in their

attenuation properties and dimensions. SIFI-

F (B84111F) has the smallest dimensions

and covers the range of normal require-

ments on interference suppression. Even a

limited available space is usually sufficient

for SIFI-F, as the package of the 10-A ver-

sion including terminals and attachment clips

requires a footprint of only 60 x 60 mm2.

In the case of higher requirements on atten-

uation properties, SIFI-G (B84112G) is rec-

ommended. Especially at frequencies below

1 MHz, it offers an improved asymmetrical

insertion loss compared with SIFI-F. Fig. 2

shows the asymmetrical insertion loss (com-

mon mode) of the 3-A versions of SIFI-F

(B84111FB30), SIFI-G (B84112GB30) and

SIFI-H (B84113HB30) as a function of the

frequency.

If the insertion loss of SIFI-G is not sufficient,

then SIFI-H (B84113H) should be used. This

is a two-stage filter with the highest insertion

loss. Starting from as low as about 0.1 MHz

up to about 50 MHz it reliably reduces the

conducted symmetrical and asymmetrical

interference voltages. Depending on the

interference source, this allows high require-

ments such as the limits of class C1 to EN

61800?3 (2004) for conducted disturbance

voltages to be observed even for strong

sources of interference.

When the suitable SIFI family (F, G or H) has

been selected on the basis of the attenuation

requirements, the leakage current must be

considered. All new SIFI filters are available

in both standard and medical versions. The

standard version has, depending on the type,

a leakage current in the range from 0.5 to 3.5

mA. In the version for medical technology, the

leakage current was limited to a maximum of

0.002 mA, as strict limits apply in this sector.

E M C

28 Bodo´s Power Systems® October 2009 www.bodospower.com

EMC FiltersNew applications thanks to lower leakage current

The SIFI series of 2-line filters has proved itself in numerous applications over manyyears. The new SIFI® generation with reduced leakage current is now also suitable for

medical engineering applications.

By Volker Scharrer, EPCOS

Figure 1: Selection guide for EMC filters of the SIFI familyAll filters of the three SIFI families are now also available with a reduced leakage current ofonly 0.002 mA, making them suited for applications in medical technology.

Figure 2: Attenuation curve of various SIFItypesAsymmetrical insertion loss for 3-A versionsof SIFI-F, SIFI-G and SIFI-H as a function ofthe frequency.

When selecting the rated current, filters are

available from 3 A to 36 A. The rated voltage

is 250 V DC/AC for all types. Optimization of

the components used allows the maximum

ambient temperature to be increased to 100

°C, corresponding to climate category

25/100/21 to IEC 60068-1. This leads to a

reduced and thus improved current derating

at higher temperatures. The complete SIFI

range has naturally been approved to UL,

cUL and ENEC. This facilitates the approval

of the end product for the North American

and European markets. The connections

used for SIFI-G and H are tab connectors up

to 16 A and threaded stubs starting from 20

A. SIFI-F has tab connectors up to 20 A and

threaded stubs from 25 A.

Broad range of applications

The medical version is used wherever the

leakage current must be kept low. This can

be the case for X-ray equipment, computed

tomographs, ultrasonic and other diagnostic

equipment.

Effective and reliable EMC is particularly

important in medical equipment, as patients

come into close contact with medical diag-

nostic equipment. Accordingly, leakage cur-

rents must be kept low and equipment mal-

functions must be excluded, especially in

life-support systems. But the SIFI medical

version may also be used in other applica-

tions where the leakage current must be lim-

ited – e.g. where a ground fault circuit inter-

rupter is used.

The standard versions of the SIFI are used

in almost all areas of industrial electronics,

both in AC and in

DC applications.

Thanks to their high

performance and

compact dimen-

sions, SIFIs are

incorporated into

welding equipment,

measuring equip-

ment, machine con-

trol systems as well

as fitness equip-

ment and the

telecommunications

equipment. They

have also proven

themselves many

times over in power

supplies for small

machines, switching

cabinets and fan

installations.

They are also used

increasingly in solar

inverters. Fig. 3

shows an example

of an disturbance

voltage measure-

ment of a solar

inverter. In the first

case – without EMC filters – some of the val-

ues are significantly above the limits stipulat-

ed for class A (industrial environment). In the

second case, a SIFI-G B84112GG125 (25A)

with enhanced attenuation was used. It

allows the noise voltages to be reduced to

below the class-A limits to DIN EN 55011

(2007).

All SIFIs are now available from stock in

small quantities. The ordering codes start

with B84111F* (SIFI-F), B84112G* (SIFI-G)

and B84113H* (SIFI-H). The predecessor

SIFI product families, SIFI-A, SIFI-B, SIFI-C,

SIFI-D and SIFI-E, are also still being manu-

factured. However, new SIFI versions should

be preferred for new designs. In general,

SIFI-A can be replaced by SIFI-F, SIFI-B by

SIFI-G and SIFI-C by SIFI-H.

A frequently occurring fault source in prac-

tice is a lack of separation of interference-

emitting and filtered lines. This can result in

a coupling of interference and considerably

reduce the filter effect. So care must always

be taken to ensure spatial separation of

unfiltered and filtered lines. Where this is not

possible, grounded metal parts or cable

channels should decouple the lines from

each other. Another solution would be a

right-angled crossing or twisting of the lines.

This can reduce the magnetic coupling.

When shielded lines are used, the shielding

must be connected to the reference potential

along a large area on both sides.

www.epcos.com

29www.bodospower.com October 2009 Bodo´s Power Systems®

Figure 3: Disturbance voltage measurementDistrurbance voltage against frequency with-out EMC filter (above) and with EMC filterB84112GG125 (below). The blue curvesshow the measured average peak values,the red curves show the results of the quasi-peak measurement.

When mounting the filter, the package

should as far as possible be connected

with ground across a large area (surface

without lacquer) of the other modules. This

is particularly important for interference fre-

quencies >1 MHz. At such high frequen-

cies, a ground connection via a cable

strand must absolutely be avoided (see

diagram).

A cable of 10 cm length has an impedance

of about 140 nH. This already results in an

impedance of 17 Ù with an interference

frequency of 20 MHz, for instance. This

impedance is too high for a ground con-

nection, so that practically no filter effect is

achieved in the higher frequency range

irrespective of the filter used. All filter con-

cepts will fail in this case, whether they

have one or two stages. Only a low-imped-

ance wide-area ground connection will help

in this case.

Figure 4: Correct ground connection

30 Bodo´s Power Systems® October 2009 www.bodospower.com

While traditional induction hobs require very accurate positioning of

the pan, multizone designs deliver efficient heating of the pan irre-

spective of its position. The challenge, however, is delivering a multi-

zone design that remains commercially viable and minimizes compo-

nent count.

Induction heating occurs due to electromagnetic coupling between

the source (a coil driven by a power converter running at several tens

of kHz) and a ferromagnetic pan. To work at full efficiency the relative

position between the coil and the pan must be well defined - other-

wise coupling becomes weaker, with the net result of increased con-

verter reactive/active power ratio. For that reason, areas on the sur-

face of the cooker are usually painted over with glass-ceramic sub-

strate to indicate where to position the pan.

Multizone induction heating, on the other hand, allows efficient pan

heating irrespective of position. This is typically achieved using a

large number of small coils, each driven by one or more adjustable

power, high frequency converters. An intelligent detection system

works out the pan’s position and activates only those coils that can

achieve full coupling. To increase cooking surface resolution (improv-

ing coupling), requires a larger number of coils, and thus the number

of the converters can quickly increase beyond an economically viable

level.

Among the requirements for a multizone design are the need to acti-

vate heating sources in any possible subset configuration (the pan

could be any sort of shape, or in any orientation, but must still be

heated across the whole contact area) and minimizing the compo-

nent count and cost of the power conversion system. To date,

designs have tended to rely on high power relays to connect/discon-

nect the coils from a relatively small number of converters, but this is

costly. The goal, therefore, is to find a way of having sufficient coils,

while reducing the number of converters (and their power ratings),

and without using relays.

A new approach

One approach is to construct a modified switching matrix of elemen-

tary resonant converters. By proper connection of the converters to

each other and to the resonant circuits composed of coils and reso-

nant capacitors, any single coil can be activated and independently

controlled. Converters are of the half-bridge resonant type, each

operating at a fixed frequency (close to the coil-capacitor network

resonant frequency). This has the advantage of automatically elimi-

nating the interference between frequencies that can lead to acoustic

noise. Fixed frequency operation is made possible by controlling the

power of each coil via phase shift techniques, instead of duty cycle or

frequency control methods.

Now let’s consider a novel wiring scheme that can minimize the num-

ber and size of the power converters.

Matrix design

Figure 1 shows a simplified version of the proposed switching matrix,

which has been limited to a six-coil capacitor network for clarity. This

matrix is composed of elementary converters and uses neither relays

nor solid state switches. Converters are connected to each other

through series resonant circuits, which are damped by the pan,

whose loading acts an equivalent resistance. The circuits are laid out

in such a way that, by turning on any pair of converters, the heating

coil at the cross point is activated. The connection of the networks is

such that the final design resembles a full-bridge configuration.

Each constant frequency converter pair is operated at a constant

duty cycle of 50%; with a reference signal used to ensure phase

shifting between the two converters. This provides control of the

power delivered to the coil. The low level signal network, controlled

by an ON/OFF command and a power reference level, is provided by

a central controller unit. Because of the phase shift control, when two

or more converters are operated at the same time to control multiple

coils, each converter pair only addresses its own series resonant cir-

cuit, and does not interfere with other converters. Unlike previously

proposed solutions, coils are not placed in parallel to each other

T E C H N O L O G Y

Now We are Cooking A new approach to induction heating design

Looking at a new ‘multizone’ design that allows efficient heating while reducing the numberand power rating of converters and eliminating the need for relays or solid state switches.

The demand for induction hobs - in which electromagnetic coupling between a ferromagneticsaucepan and concentrated coils in the cooker’s heating element are used to provide heat

energy - continues to grow.

By Cesare Bocchiola, International Rectifier

Figure 1 – Simplified coil-converter matrix

31www.bodospower.com October 2009 Bodo´s Power Systems®

using relays, with the result that the circuits do not change their reso-

nant frequency.

Independent control of coil power

Consider coils C01_02 and C02_02; their activation requires convert-

ers M01, M02 and N02 to be operated simultaneously (converters

M01 and N02 driving coil C01_02, while M02 and N02 drive

C02_02). Converter N02 is shared between the coils, but, because

each converter operates at the same frequency and with a 50% duty

cycle, simply choosing different phase shifts between converter pairs

easily allows independent power control as shown in Figure.2).

In this way, for a phase shift of 0°, the power delivered to the coil will

be zero and for 180° shift the power will be the maximum achievable

by the converters. Powers between the minimum and maximum are

obtained by corresponding phase shifts between 0° and 180° Figure

3 shows the linear relationship between power and phase delay.

Less converters and lower power ratings

In Figure.1, the converters are shown connected to the coil in a stan-

dard matrix configuration. Such a configuration, however, can present

limitations.

In the standard matrix n1, n2,….., nN can be used to describe the

converters in a row, and m1, m2,….., mM the converters in a col-

umn.. Each coil needs a different power level, which can be denoted

by P1, P2, P3 and P4. Converter n2 will have phase Ph_n2 and m3

will have phase Ph_m3; the coil network between them will see the

difference Ph_n2-m3. A power level of P2 is delivered to the coil net-

work at the intersection between n2 and m7. Converter n2 is already

activated, so it will just be necessary to activate converter m7, with a

phase Ph_m7, such that Ph_n2–m7 will provide the power P2.

Again, to deliver power P3 to the coil intersecting n7 and m3 (with

m3 already ON), it will be just sufficient to activate converter n7 with

a phase Ph_n7, such that shift Ph_n7-m3 provides the power. Now

trying to control P4 at the same time is not possible. In fact, n7 and

m7 are already operating and their mutual phase shift is fixed by the

power they are delivering to the other coils. A limit of a standard

switching matrix is that only any upper (or lower) semi-diagonal sub-

matrix of coils has elements whose power may be independently

selected.

To overcome matrix limitations, it is necessary to employ an adjacent

coil strategy. The basic idea is that adjacent coils must be independ-

ently turned ON/OFF, but when ON they do not really need to be

driven at different power levels. While this seems restrictive from a

theoretical point of view, it is not from a practical standpoint,

because:

With big pans covering more than one coil, adjacent coils share the

same power level since they are coupled to the same pan.

With small pans only covering one coil, adjacent coils are not driven

at all.

A modified switching matrix can be designed, realizing the benefit of

adjacent coils, as illustrated schematically in Figure.4.

The blocks represent converters, while circles denote coils. This

modified matrix is based on two key rules. Firstly, adjacent coils must

never connect to the same pair of converters, otherwise the heating

resolution will be reduced. Secondly, in the case that two adjacent

coils need to be turned on, requiring two pairs of converters, the

same converters are allowed to drive another coil, which must be

adjacent to the first two.

The general formula applying to this approach is:

Ncoils = Nconverter * (Nconverter –1) / 2

Thus, the maximum number of coils that may be driven by the six

converters shown in the diagram is 15.

Each converter may drive up to five coils. Out of the 15 coils, only

five are actually truly independent from each other, but by proper

wiring, non-independent coils can be placed in a way that a small

pan which needs a single coil can be independently controlled, while

bigger pans covering several adjacent coils can be heated by activat-

ing these coils with the same power level.

www.irf.com

Figure 2 – Converter Pair Block Diagram

Figure.3: Coil power & current versus phase shift

Figure.4: Modified switching matrix

T E C H N O L O G Y

32 Bodo´s Power Systems® October 2009 www.bodospower.com

For high speed functions every signal that must be connected from

one integrated circuit to another slows the system down by the addi-

tion of significant input/output capacitances for each pin and PC

board routing which requires larger line drivers with more cost and

more board area.

In the realm of integrated circuits, this constant need for higher inte-

gration has for the most part been achieved through constant

improvements in the photolithography used to fabricate the devices.

Equipment has evolved from contact printing with .1 mil resolution

through projection printing, high resolution steppers to direct write on

wafers with E-beam technology where we now talk about nanometers

of photo resolution. For awhile this progress has followed what has

gotten to be known as Moores’ law. This defines the ever-increasing

complexity of a product that can be integrated onto a piece of silicon.

This has defined the progress over time for microprocessors, silicon

memory, and ASICs. While process complexity has increased to be

able to define these extremely small feature sizes, today’s basic lat-

eral CMOS transistors would be recognized by its original inventor.

This drive for continual improvements and integration has been

around even before semiconductors where the primary driver. Figure

1 is a diagram that highlights this constant evolution in technology

pushing for ever more complex systems.

There has been a similar drive for smaller, less costly and higher per-

formance power devices. However advancements in the RDS(ON)

(on resistance) of the power devices while taking advantage of

improved photolithography has been enabled by new and more com-

plex structures. The current power MOS devices developed do not

use the traditional planar topologies that had been used for many

years, but they have been replaced with much more complex trench

or charge-balanced technologies. Both of these approaches add

process complexity to significantly lower the specific on resistance of

a given MOSFET as compared to the older planar technologies.

These new power structures have driven an improvement curve for

the specific on resistance per unit area of a MOSFET. Figure 3

shows a generic curve for the on resistance of a typical 50v MOSFET

process and is similar in shape to Moores’ Law but for Power

devices.

As system complexity grows, it becomes natural to want to combine

both higher performance mixed signal IC functions with higher power

silicon switches. However, when you look at the process complexity

required for combining high performance mixed signal control with

significant power handling capability it quickly becomes obvious there

has to be a better way than to just integrate everything into a bigger

more complex single piece of silicon. In addition to the process com-

plexity one major drawback is for the high performance vertical

DMOS or other power structures the back side of the die is the drain

(or collector) of the power device with current flowing vertically

through the die. In contrast most mixed signal ICs have a P-sub-

T E C H N O L O G Y

Mixed Signal and PowerIntegration Packaging Solutions

Multiple-die packaging techniques for very mixed silicon processing requirements

Even before the first transistor was invented, there has been a constant drive to integratemore and more functionality into a single product. There are the obvious cost benefits to

put more functions into the same package or die area, but there are also performancebenefits by integrating more devices into a single product.

By Jim Gillberg, Fairchild Semiconductor

Figure 1: Kurzweil’s extension of Moore’s law

Figure 2: Example of Planar vertical DMOS, Vertical Trench andCharge Balanced Power MOSFETs

33www.bodospower.com October 2009 Bodo´s Power Systems®

strate material where the back of the wafer can serve as a system

ground. Having the back side of the die being the output from the

power device can cause other issues related to handling over or

under voltage transient conditions that might cause unexpected

results.

Because of the issues in trying to integrate the process complexities

of the advanced power structures with high performance mixed signal

designs the use of advanced packaging techniques normally will pro-

duce the best results.

Following is an example of a complex high power automotive sole-

noid driver. Two different approaches were taken. One combining

the high power switch with the high performance control block into

one piece of silicon and the 2nd an example how using advanced

package and isolation techniques can reduce the cost of a product. A

series of generic assumptions are made on the silicon cost of each

product to obtain a comparison of the two approaches:

Assumptions: (Following is used for illustrative purposes and are

generic costs and mask counts)

Vertical DMOS 6 inch wafer 9 masking levels @ $30/level

High Voltage BCD DLM process – 24 masking layers $30/ level

Using a normalized area of the integrated solution on the left to be

1unit area: then the power fet and control die (on the right side)

each have an area of about .3 units as compared to the larger mono-

lithic solution. Thus the total silicon area is 40% lower using the two

die vs. the integrated solution.

T E C H N O L O G Y

Figure 3: RDS(ON) Vs time

Figure 4: Alternate Approaches to Smart Power Products

dc-dc converters isolated board mount isolated chassis mount non- isolated regulators LED driver modules

www.v-infi nity.com

switching power supplies embedded power open frame chassis mount multi-blade

V-INFINITYPOWERING INGENUITY

INTRODUCING THE NEW

CUI Europe

Phone +46-40-150565

Krossverksgatan 7H,

216 16 Limhamn, Sweden

external adapters wall plug desk-top multi-blade

To obtain a reasonable cost comparison you now have to take into

account both the area difference and masking complexity of the three

devices. Using the assumptions above for wafer costs would gener-

ate about a $1.00 cost for the integrated solution while generating a

combined $0.40 cost for the two die solution. Thus by selecting an

architecture dividing the power from the control in this example gen-

erates a 60% cost reduction in the silicon. While there would be

some cost increase in the assembly of the additional die in the pack-

age the combination of silicon and packaging costs for this example

will be much lower for the divided solution.

For this example to hold true the power section of the device must be

a major portion of the overall die. Again in this example the power

portion of the integrated solution is approximately 50% of the total sil-

icon area. Thus a major cost reduction through partitioning should be

expected. In addition, the area of the silicon required for the power

region has to be large enough that the silicon cost reduction can

overcome the increased cost of the assembly. So for higher imped-

ance power devices, above about 100 milliohms of rdson, a monolith-

ic solution normally will have the lowest cost. While for power sys-

tems requiring MOSFETs with less then 50 mOhms of on resistance,

a partitioned architecture will normally be lower cost. However this

tradeoff has to be continually evaluated as new technologies can

change the cost and area assumptions used above.

One of the major issues that must be over come when combining

power and control in a single package, is that the back of the power

device is normally the drain or collector of the power switch, so the

control die must be electrically isolated from the die attach area that

the power die is mounted on. Since the power die is typically a verti-

cal conducting device, a good low resistance high temperature solder

die attach is normally used. There are several ways to approach the

electrical isolation required between the power and control devices.

Separate the die attach areas:

Use of non conducting epoxy for the control die.

Use of polyimide tape die attach for the control die.

Use of a back side laminate on the control die.

In the example shown two types of isolation are used. To start there

are three separate die attach areas in the package show above in fig-

ure 4 on the right. ( left, right and center) Each of these die attach

areas or paddles can have a different electrical potential. On the left

and right die attach areas the power device is soldered to the paddle

while the control IC uses a backside polyimide laminate that electri-

cally isolates the die from the paddle that the power device is

attached to.

Each technique for isolation has its advantages and disadvantages

as regards, cost reliability and manufacturability.

Some packages like the MLP or PQFN devices (similar to the pack-

age shown in figure 4) can easily accommodate multiple die attach

areas. But traditional power packaging such as the TO220 or TO252

which have a thick header or tab are not easily divided into two sepa-

rated electrical areas. Use of a non-conducting epoxy die attach is

one of the easiest isolation solutions to implement but this approach

has been shown to be susceptible to reliability issues related to pin

holes in the epoxy die attach.

Polyimide tape is being used successfully but the die attach area

must be larger then the attached die area to account for the align-

ment tolerance of the die to the polyimide tape and thus takes up

more area then the backside laminate solution mentioned. For the

back side laminate solution a film is attached to the entire backside of

the control die wafer and then the die are sawn from the wafer. In

this way each die has the polyimide film attached to the back of the

die and the need for additional area to account for the alignment vari-

ability when attaching the die is eliminated. This can be particularly

beneficial when the control die is being attached on top of the power

die, allowing a smaller power die to still accommodate the die on die

assembly requirements. Figure 5 shows the back side laminate and a

wafer with the laminate attached.

So as we continue to follow the inevitable path of higher level integra-

tion and more “systems on a chip”, and we begin to mix high power

capabilities into these systems, you will find more often than not the

product you are evaluating actually has several silicon die molded

into it. So advanced multiple-die packaging techniques continue to be

used to solve the problem of how to integrate products with very

mixed silicon processing requirements while minimizing product

costs.

www.fairchildsem.com

T E C H N O L O G Y

34 Bodo´s Power Systems® October 2009 www.bodospower.com

Figure 5 Backside laminate isolation

Figure 6 various multiple die assemblies

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36 Bodo´s Power Systems® October 2009 www.bodospower.com

Split decisions between linear regulators and switch mode regu-

lators

Especially in Measurement and Control Technology, where a high

quality of output voltage with minimal interference is of great impor-

tance, linear regulators do fulfil the demands, as they separate the

input voltages via a transformer, stabilize them with a linear regulator

and filter them extremely effectively. However, they are large and

heavy, with a low efficiency. Switch mode regulators work very effi-

cientlly, have small dimensions and a low weight. This is achieved by

switching the input voltages at high frequencies (50 to 500 kHz) and

then isolating them galvanically with a small transformer. Through the

following regulation and filtration with the aid of a pulse width modu-

lation regulator the required output voltage is obtained. The multiple-

voltage changes do however create high frequency interferences,

which can be found as ripples and spikes on the output voltages. The

classic switch parts of a network have cost many developers much

time, as the anti-interference measures for the voltages are very

costly and time consuming.

Interference-low input and output voltage

With ‘slimpower’ Schroff has created a 19” power supply range that

combines the positive properties of switch mode regulators as well as

linear regulators (table 1). During the design and development of the

power supplies, input and output voltages with the least possible

interferences were considered, to lower the typical interferences of a

switch regulator. The use of SMD performance components and lin-

ear technology reacts positively on the interferences due to the low

parasitic effect. Ripples and spikes lie below the tolerance of 10 mV

for low emission units. Simultaneously, both the incoming interfer-

ences and HF emissions have been considerably reduced. The lev-

els are at least 15 dB below the tolerance levels set by EN 55022

Class B.

Small dimension, large performance

During development further emphasis was put on small dimensions

and high output performances. The units are arranged as a standard

Euroboard, 3 U and a depth of 160 mm (Euroboard format) and a

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

The Correct Power Supply The choice has become easier

To find a suitable power supply for your own application: developers and project engi-neers can tell many a tale about this. Despite the fact that there is an enormous choice onthe market, the one that fits the bill exactly is never amongst them. Compromises regard-

ing dimensions, quality of output voltages, performance and price have to be made.

By Dipl. Ing. (FH) Oliver Kistner, Principal Engineer Power Electronics, Schroff GmbH, Straubenhardt, Germany.

Figure 1: Product photograph of slimpower

Figure 2: Comparison of residual ripple and spikes between theswitch regulator – slimpower

37www.bodospower.com October 2009 Bodo´s Power Systems®www.bodospower.com September 2009 Bodo´s Power Systems®

width of only 3 HP (15 mm) with a standard H15 connector. For the

transformer instead of the common copper coils, etched copper

channels, which have been placed on a board retainer by multi-layer

technology, are used. This multi-layer construction is a planar trans-

former and fits exactly between two ferrite cores and saves a lot of

space.

As the real primary switch regulator a highly integrated circuit is used

for these power supplies and this element combines a complete

pulse width modulator including the power transistor. Cooling takes

place via a SMD-cooling unit, which is thermally linked with flexible

heat conducting material to the housing of the power supply. Despite

the small dimensions, output performance of 5 V at 30 W, 12 V/15 V/

24 V at 42 W in a temperature range between 0 to 50 °C and an effi-

ciency of 80 % is obtained, while no fan cooling is needed. Depend-

ing on the application, the power supplies can be operated with or

without redundancy diode. During redundant operation the current

share operation guarantees an even distribution of power at the par-

allel switched ports. The V/I starting point for the parallel operation is

configured ‘hard’ or ‘softly’ and allows the user to run high capacity

loads such as batteries with the unit. This is a considerable advan-

tage for portable measuring instruments, for instance. The indication

of the output voltage is also configured as ‘high active’ and ‘low

active’ signalling. The secondary power limitation, over voltage pro-

tection (OVP) with automatic restart and the over temperature protec-

tion improve the function and safety of the power supplies. The

MTBF values of these power supplies lie at more than 400.000 hours

at 40 °C ambient. With a range of 85 to 254 VAC (120 to 360 VDC)

worldwide use is possible.

www.schroff.de

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

Figure 3: Transmission interference curve slimpower

Table 1: Comparison 19” linear regulator – 19” switched mode regu-lator

Switched mode regulator Linear regulator

Power Density high (33 W/TE) small (4 W/TE)

Weight per Watt small (3 g/W) high (32 g/W)

Efficiency high (75...95 %) small (40...65 %)

Input Voltage Range high (90...264 VAC) small (207...253 VAC)

Ripple and Noise middle (50...100 mV) small (< 2 mV)

Emissions EN 55022 class B VDE 0875 class K

Regulation Speed middle (0,1...1,5 ms) fast (< 50 μs)

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38 Bodo´s Power Systems® October 2009 www.bodospower.com

The family of equipment which is described

in this article deals with the test of static

parameters (over 25 listed), of discrete com-

ponents as well as semiconductor modules,

such as bipolar transistors, IGBT's, MOS-

FET's, thyristors, diodes, resistors (thermis-

tors). The objective, which has been effec-

tively reached, was a typical average rate of

10 tests per second. Although the objective

is production testing, the equipment is also

usable for lab measurements and compo-

nent characterization. The original concept

consists in the fact that every function in a

test equipment had to be considered as an

independent module for itself, in order to

make possible fast data acquisition, as well

as easy and quick replacement of defective

parts, since high-speed production testing

needs also efficient and low time-consuming

troubleshooting. This concept is pushed

even further: modules can be used inde-

pendently, e.g. plugged in a 19 in. rack,

which, in turn may be installed in a user-

designed structure.

Main Modules

The most important modules are of course

power modules (also further called genera-

tors). These modules are the voltage gener-

ator and the current generator, delivering

typically half-sine or trapezoid pulses.

The voltage module delivers pulses having

an amplitude ranging from 20 to 2200 V, with

current capability of 0.1 to 100 mA. This

generator works as a voltage source with

programmable current limitation. The voltage

and current are measured on the flat part of

the trapezoidal pulse or at the peak of the

half-sinewave. This module is mainly

designed for the measurement of the block-

ing voltage and the leakage current of

devices under test.

The current generator delivers pulses having

an amplitude ranging from 2 to 200 A. Two

other module sizes exist with 2 – 500 A, and

2 – 1000 A. The pulse rate reaches 20 Hz.

This generator acts as a current source.

Equipped with a gate driver for triggered

devices, it is mainly designed for forward

voltage drop (0 -10 V) of components. The

measurement is performed at the end of the

trapezoidal pulse or at the peak of the half-

sinewave.

Optional Modules

Gate Characteristics Tests

The Module IGE (for IGBT and MOSFET

tests) unit comprises a 5-100 V generator of

rectangular pulses of 40 – 100 ms duration,

for the test of I[GES]and I[GSS], and a 0.1 –

100 mA generator of rectangular pulses of 2

– 10 ms duration, at a maximum frequency

of 20 Hz, for the test of VGE(th) and

VGS(th). The module IGT (for thyristor tests)

comprises an anode 6 or 12 V power gener-

ator with a series resistor (1, 2 or 6 W), with

a maximum anode current of 12 A, and a

gate ramp current generator, adjustable in

two ranges (0.5 – 50 mA and 5 – 500 mA),

at a maximum frequency of 20 Hz. The IGT

and VGT values are measured with a delay

defined by an RC time constant of 100 μs

IH/IL Test and Kelvin Contact Control

The IH/IL module (for thyristor tests) com-

prises a trapezoidal pulse current generator

and a 6 or 12 V anode supply. The Kelvin

Contact Test module controls the connec-

tions of the Device Under Test (DUT), using

a rectangular pulse of 24 V (50 mA).This test

is important in the sense that it allows for the

detection of a fault in the internal connec-

tions of a semiconductor module.

Output Matrix

Although it is mentioned as an option, this

module plays a prime importance role. In

order to connect more than one module to a

DUT, i.e. performing several different tests in

a sequence, an electro-mechanical device is

necessary. The Matrix module, which pro-

vides for a minimum of 6 up to 63 low level

signal lines, and for a minimum of 2 up to 32

power lines.

To illustrate the role of this module, Fig. 1 is

selfexplanatory, showing a typical test sys-

tem equipped with several modules, with

output connection to a single DUT (one test

head output). The matrix is using high-

speed, high-reliability relays able to connect

high currents or voltages and low level sig-

nals between the various modules and the

DUT. Therefore it is typically a heavy-duty,

key element of the test system. Millions of

operations are possible, however a periodi-

cal auto-test of the quality of the relay con-

tacts is performed. This will be explained fur-

ther in the section dedicated to the software

control.

D E S I G N A N D M E A S U R E M E N T

A Modular Approach for Production High speed testing of power semiconductors

With an experience that started in the early 1960's, LEMSYS developed in the beginningof the 1990's a modular approach of power semiconductors commencing with the test ofdynamic parameters. The main concern of this development was the possibility to build ina relatively short time custom-sized equipment, according to the user's needs and likely to

be easily upgraded in terms of power capability. With the static parameter testing, thenecessity of a modular concept revealed even more acute in the sense that high test rate

capability is mandatory.

By Gérard Cuénoud, LEMSYS SA, Switzerland

Figure 1: Multiple Module test system

39www.bodospower.com October 2009 Bodo´s Power Systems®

The test equipment connections to the DUT

are grouped on an output connector having

power connections at pin locations 1 to 32.

The Power Matrix allows to select which

lines are connected to the output connector.

As shown in Figure.2, the user selects what

relays have to be energized, according to

the chosen output connections, whereas the

function of each line (here positive and neg-

ative pole of a voltage generator) is deter-

mined automatically by the active test mod-

ule (shaded boxes, at the bottom of the fig-

ure).

The low power connections (63) of the out-

put connector (pin locations N° 101 to N°

163) are selected by the low level matrix

(see Figure 3). Similarly to the power matrix

system, the user can select to what connec-

tor pins the low level lines (gate generator

signal, measurement sense terminals) will

be connected. This is shown in the upper

part of the figure. As per the power matrix,

the selected lines are auto-

matically defined by the

active test module (here the

measurement circuit of an

IGT/VGT module, shaded

boxes in the lower part of

the figure). The way the

user choice is made will be

described in the Computer

Control section.

Drivers

Each module contains a

special driver unit using a

microprocessor. This unit

delivers the references, lev-

els and timing to the generator(s) and meas-

urement circuit(s) according to the test con-

dition required.

The presence of the driver unit in each mod-

ule allows for a simplified communication

with the personal computer (PC) which con-

trols the entire equipment. Another feature of

this approach is an increased test speed.

Operator's Interface

The control of the test equipment is per-

formed by a personal computer, using a

Real Time Operating System (RTOS) using

a Graphic User Interface. As the equipment

may be used according to four different

modes of operation, such as:

1.) Production mode;

2.) Laboratory mode, for component charac-

terization;

3.) Edition for the elaboration of complete

test sequence;

4.) Edition mode for the elaboration of the

DUT characteristics;

A simple, easy to learn language is used, as

well as graphic presentation, where fields

allow for a quick introduction of DUT identifi-

cation, test conditions, etc.

Fig. 4 shows an example of laboratory test,

with the test results in the lower half of the

screen, with comments in the upper part.

Engineering Interface

The programming language, for engineering

purposes remains very simple, though a little

more complicated. It is needed for the

preparation of tests and test sequences.

One preliminary important step is to define

the output connections of the tester to the

DUT through the connector and the test

head. The example of Figure 5 illustrates the

case of a 6transistor IGBT module. Lines

preceded by a # are comment lines. The

second line shows in what order connections

for collector, emitter, gate and sense are

given (reminding that 1 to 32 are power

matrix outputs and 101 to 163 are low level

matrix output)

The following figure shows the sequence

programmed for the VCESAT test (Figure 6).

Note that the #inc-lude and #define lines are

compulsory.

www.bodospower.com October 2009 Bodo´s Power Systems®

D E S I G N A N D M E A S U R E M E N T

Figure 2: Power Matrix

Figure 3: Low Level Matrix

USER CHOICE PROGRAMMABLERELAYS

Open relay contact

Closed relay contact

Figure 4: Laboratory Mode Example

Figure 5: Connection Attribution

# DUT file for Device XYZ

# ; C ; E ; G ; Ea ; Gs ; Es ; Cs

T1 ; 10 ; 1 ; 102 ; 103 ; 121 ; 103 ; 127

T3 ; 10 ; 4 ; 108 ; 107 ; 139 ; 107 ; 127

T5 ; 10 ; 9 ; 112 ; 111 ; 140 ; 111 ; 127

T2 ; 1 ;13 ; 114 ; 117 ; 141 ; 115 ; 103

T4 ; 4 ;13 ; 116 ; 117 ; 142 ; 115 ; 107

T6 ; 9 ;13 ; 118 ; 115 ; 143 ; 117 ; 111

# end

Figure 6: VCESAT Test Sequence

#include "prolog.h"

#define DUT_UNDER_TEST

"my_dut_file"

/* VCESAT TEST */

strcpy(vcesat.customer_name,"VCE-

SAT_low");

strcpy(vcesat.dut, DUT_UNDER_TEST);

strcpy(vcesat.subdut, "T4");

vcesat.Vg = 15.0; /* 2 to 20 V */

vcesat.Rg = 20.0; /* 20 or 50 Ohms */

vcesat.I = 50.0; /* 2 to 500 A */

vcesat.t = 0.5; /* 0.2 to 1 ms */

vcesat.limit_min = 1.0; /* V */

vcesat.limit_max = 4.0; /* V */

vcesat_result = exec_vcesat();

#include "epilog.h"

40 Bodo´s Power Systems® October 2009 www.bodospower.com

Maintenance Interface

As already mentioned in section 3.2.3, the

output matrix is a key element of the test

equipment, which has to be periodically

checked. Therefore, a "Check Matrix" utility

program allows for the detection of any relay

failure. For this operation, the tester must be

running, with all DUT connections removed.

Three controls are performed:

1.) Detection of any contact short-circuit on

all relays:

2.) Check of proper functioning of the auxil-

iary relays;

3.) Check of the proper functioning of the

main relays.

The result is displayed on the screen, with

identification (and localisation) of the defec-

tive relay(s). Then the defective part(s) can

be replaced, or the complete matrix module

itself, when an short time is needed to start

with new semiconductor tests.

Dialog with a Handler

Another module, which has not been men-

tioned in section 3.2, is the Handler Function

Module which manages the information flow

between the PC and a handler for automatic

production testing. The logic signals are + 5

V d.c., with active level at 0 V (negative

logic).

BinCode signals (for device classification),

and AdaptorCode signals (for verification of

the adaptor with the DUT and sequence a

requested) are exchanged.

Other Features

The PC can compute test statistics. Among

others, are also the possibility of sorting the

devices (category classification), and con-

verting the result files into *.csv files compat-

ible with Windows Excel.

Tester Architecture and

Block Diagram

A typical 500 A / 2200 V

equipment is represented

in Figure 7, where the

easiness of the mainte-

nance appears quite obvi-

ously.

The PC is linked to the

test equipment through a

RS 232 optical fibre con-

nection, which runs,

inside the equipment to

the different module driv-

ers. Therefore the com-

puter is electrically isolat-

ed from the tester, which

fulfils two tasks:

First the electrical safety

of the operator, and sec-

ond, a noise-free control

operation. The computer

is also equipped with an

Ethernet connection for

data transmission with

other computers, and

remote control. A modem

connection is available for

downloads of software upgrades and for

remote maintenance. A Mains and Safety

module (bottom left) distributes the connec-

tions to the mains, to the test command box

and the different safety connections (in par-

ticular with the test head protection lid). The

generator and measurement modules, repre-

sented in the center, are, from top to bottom:

a 2200 V and a 500 A generators, a gate

generator. Top right is the Matrix Module,

where the five blocks (center right) represent

the user configurable output lines.

Typical Module Architecture

The block diagram of a voltage module,

delivering 20 to 2200 V, with adjustable cur-

rent limit from 0.1 to 100 mA, is shown in

Figure 8.

Safety

For the operator's safety, the control is

designed in accordance to the European

standards. The test equipment is protected

by a conducting and grounded cabinet. The

opening of any side panel of the tester cabi-

net will shut down the power supply of all the

generators able to supply hazardous volt-

age. The output terminals of the tester will

be short-circuited and grounded as well,

whereas the supply of the control elements

such as the computer or the function mod-

ules will not be affected. The DUT test area

must be protected by an enclosure.

The tester will check the position of the

enclosure before starting any test. As long

as the enclosure is not on its closed position,

the high voltage output terminals of the

tester will be short-circuited and grounded.

no test can be started. Before the execution

of the first test after start up, the protection

enclosure has to be opened and closed

once. During this cycle test, the proper func-

tion of the safety circuit and devices are

checked.

www.lemsys.comFigure 7: Typical Test Equipment

Figure 8: Voltage Module Architecture

D E S I G N A N D M E A S U R E M E N T

42 Bodo´s Power Systems® October 2009 www.bodospower.com

The design of power converter includes necessarily the calculation of

power loss and temperature rise in the semiconductors and heat

sink. For a reliable design the temperature ripple of the silicon should

also be considered. The temperature ripple mainly determines the life

time of the semiconductor (number of cycles to failure). The junction

temperature is related to the heat sink temperature. Mostly the heat

sources are not homogenous distributed over the heat sink. There-

fore, the heat distribution on the heat sink must be known.

Thermal model of the semiconductor

Numerical simulation of the junction temperature of semiconductors

is possible by setting up a thermal model of the semiconductor and

cooling system. Dynamic change of the junction temperature must be

considered. Therefore a typical thermal model is composed of RC-

networks. Figure 1a and figure 1b illustrates two possible electric

equivalent circuits for numerical simulation of the thermal behaviour

of a semiconductor device. In this model, the junction temperature is

represented by a voltage increase relative to the case temperature,

Tcase. The model in Figure 1a is called the continued fraction model.

This model reflects the physical layer structure of the semiconductor.

The RC-elements are assigned to the layer structure of the semicon-

ductor (chip, solder, substrate, base plate, thermal compound). Fig-

ure 1b shows a different approach, the so called partial fraction

model. The RC-elements in this network have no physical meaning,

except node PV-R1-C1 the junction temperature. The values of the

RC-elements are extracted from the measured heating-up curve of

the semiconductor. The values are extracted by a corresponding

analysis tool. The advantage of the partial fraction model is that with

an experimental setup the RC-elements can be calculated for every

semiconductor without the need of additional data from the supplier.

Junction temperature simulation

The input to the thermal model is the power loss in the semiconduc-

tor. The power loss depends on the circuit topology and the applica-

tion. In this paper, we are going to calculate the junction temperature

of a semiconductor in a 3-Phase voltage source inverter (VSI). The

calculation of the power loss is not shown in this paper. Reference

[1], [2], gives further information.

Beside the average junction temperature, the temperature ripple of

the semiconductor must be calculated. Every temperature change

stresses the semiconductor device. The temperature fluctuations

expose the internal connection in a semiconductor module (i.e. wire-

bonds, solder connection of DCB and base plate, underside soldering

of chips). The different length expansion of the layers causes stress

during operation, which finally leads to a failure of the semiconductor

module. The temperature model of a semiconductor as shown in fig-

ure 1a and figure 1b is a RC-network. The transfer function of the

RC-network is frequency dependent. Due to this behaviour the junc-

tion temperature swing is a function of the output frequency of the 3-

Phase VSI. In particular, low output frequencies must be considered

because they are not smoothed out by the transient thermal imped-

ance of the chip.

D E S I G N & S I M U L A T I O N

Thermal Analysis of Semiconductors

Thermal simulation predicts the junction temperature and life time of semiconductors

The design of power converter includes necessarily the calculation of power loss andtemperature rise in the semiconductors and heat sink. This article shows the procedure of

evaluation junction temperature and life time of semiconductors.

By Tobias Hofer, Negal Engineering GmbH Switzerland

Figure 1a: Continued Fraction Model

Figure 1b: Partial Fraction Model

Figure 2: Power Cycle

Figure 3: Temperature Swing

43www.bodospower.com October 2009 Bodo´s Power Systems®

Figure 2 shows the power loss at the starting procedure of a three-

phase motor. The motor current is held constant during start up. The

motor is accelerated within 0.5s from 0Hz to 50Hz. The power loss

was calculated for one IGBT and one freewheeling diode in an invert-

er leg. Figure 3 shows the relative temperature swing of the chip. At

low frequency the maximum junction temperature fluctuation is18K,

the minimum fluctuation 4K.

Case temperature

The lifetime of the power module not only depends on the tempera-

ture difference ΔTj but also on the average junction temperature of

the semiconductor. It makes a difference whether the temperature

swing of 30K is between 60°C and 90°C or between 80°C and

110°C. It takes a much smaller number of cycles to failure if the

absolute temperature is higher. The junction temperature is relative to

the case temperature of the semiconductor module. The fact that the

heat sources (semiconductors) are not evenly spread over the heat

sink, the heat distribution of the heat sink must be simulated. The

simulation tool used for the simulation in this paper represents the

heat sink as a rectangular plate. One side is cooled by convection.

On the other side rectangular heat sources are placed. The top of the

heat sources and heat sink is isothermal.

Simulation Parameters:

Heat sink with the dimension of 200mm x 300mm. The base plate

thickness is 15mm. Heat sink material is aluminium with a thermal

conductivity of 180 W/(m*K). Power loss per IGBT (including free-

wheeling diode) 60W. This results in 240W total power loss. The heat

sink is cooled by natural convection. The ambient temperature is

30°C.

Figure 4 shows the

simulated heat distri-

bution on the heat

sink. The maximum

temperature under

the semiconductor

chip TD5 is 87°C.

This simulation

shows the signifi-

cance of simulating

the heat sink temper-

ature distribution.

Lifetime calculation

Semiconductor lifetime prediction requires a statistical approach. This

demand can be met for example with a Weibull analysis of a group of

samples. The Weibull distribution is a continuous probability distribu-

tion. It is often used in the field of life data analysis. A study of the

power cycling lifetime of base plate modules was realised during the

LESIT-project. In this study the number of cycles to failure Nf was

expressed in the following form.

kB = Boltzmann constant [J/K]

Ea = activation energy [J]

Tm = average junction Temperature [K]

ΔTj = temperature ripple [K]

A,α = 302500, -5.039

A short cycling time of <10s was used. This formula gives an indica-

tion for the life time. If available, one should use the cycle to failure

data from the semiconductor manufacturer.

Conclusion

For a reliable design of the power converter it is important to calcu-

late the semiconductors temperature. The significance of simulating

the temperature distribution on the heat sink was shown. Taking the

temperature ripple and the average temperature of the semiconduc-

tor in account leads to safer designs. With adequate simulation soft-

ware it is possible to optimize the design during the development

process in an early stage. All simulations in this paper were per-

formed with SemiSimV1 [3].

References

[1] Realistic benchmarking of IGBT-modules with the help of fast and

easy to use simulation-tool

R.Schnell, U.Schlapbach; ABB Switzerland

[2] Power Cycling Lifetime of Advanced Power Modules for Different

Temperature Swings U.Scheuermann, U.Hecht; SEMIKRON

[3] SemisSimV1, www.negal.ch

www.negal.ch

⎟⎟⎠

⎞⎜⎜⎝

⎛+

Δ=)273(*

exp**KTk

ETANmB

Ajfα

D E S I G N & S I M U L A T I O N

Figure 4: Heat sink temperature distribution

Rail/marine drive controls

Wind power & solar power controls

Large motor drive controls

Bicron Electronics specializes in the design and manufacture of custom high frequency transformers for critical-use applications with frequencies up to 1 Mhz.

High IsolationSwitchmodeLoad Leveling

Gate DrivesSignal ConditioningPulse

When failure is not an option, choose Bicron.

Bicron offers the following transformer types:

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BICRONElectronics

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Bodo´s Power Systems® October 2009 www.bodospower.com

D E S I G N & S I M U L A T I O N

44

Although the trends for higher data rates and greater signal densities

of the connector tend to garner the majority focus in the electronics

industry, recent demands on the modest power connector have

brought it into the lime light – especially in the area of server and

storage applications. Here the increased data rates and higher cur-

rents associated with ever shrinking power supplies intensify the

need for connectors to support currents from 50 to 150A. Further-

more, demand for high current connectors for solar power technolo-

gies and the development of hybrid or electric vehicles is rising at a

significant rate.

In conjunction with this, each new generation of high-performance

server platforms or switching power supplies necessitates even high-

er airflows, to cool the increased number and even faster semicon-

ductors. As voltages in silicon have fallen to accommodate the faster

gate speeds, the current needed to power those devices has

increased exponentially. Thus, connector current densities, voltage

drop, inductance and packaging flexibility have become more critical

than ever before to the power engineer. Power integrity is the disci-

pline used to optimise all of these factors into a comprehensive solu-

tion to system architecture.

As one of the world’s leaders in connector design and manufacture,

Molex has developed more new power connectors in the past three

years than all of its major competitors combined. The company

already dominates the low current range of the market (3 to 18A per

pin) and is now embarking upon the high-current market (15 to 150A

per blade). Molex understands these requirements and has respond-

ed to market demand by introducing a brand new set of EXTreme

Power® products tailored to the needs of the industry.

The most familiar challenge is to fit more watts into the same or less

amount of space. For example, today the need might be for an

850W, 12V power supply, but tomorrow’s design may call for a

1200W, 12V power supply in the same enclosure. Using a simple

power formula (I=P/E) shows us that if you were to use a traditional

6-blade power connector rated at 30A/blade (120A/25mm), the 850W

power supply would work just fine (850W/12V = 70A), so 70A power

and 70A return over the 6 power blades will yield about 24A/blade.

But that same power supply putting out 1200W, would require about

34A/blade on that same connector. So what are your choices? Add

two or more power blades and go outside of your mechanical enve-

lope? Use the same 6-blade connector with an elevated T-Rise and

push above the manufacturer’s ratings? Or, change the connector to

a higher capacity connector?

Unfortunately, many power supply manufacturers and OEMs alike are

tempted to run the same connector at elevated T-Rise levels and

accept the risks associated with going over the agency rating of the

connector. This is because choosing a new connector would mean

increasing the size of the connector, hence impeding airflow and/or

increasing the cost of the power supply slightly.

The real choices to this problem are rooted in power integrity:

• Copper thickness (weight) on the PCB

• Airflow around the interconnect area and through the power supply

• Connector packaging design (more power, less space)

• Connector contact design and material selection

• Cost

Power integrity is the conscious optimisation of each one of the

points above, providing the most effective solution for the electrical

and thermal environment. Additional copper thickness and/or

increased airflow can increase the current capacity of the connector

(albeit with an added cost). Whereas a better connector design can

provide the same or more current per 25mm in a smaller package,

alleviating the need for bigger fans and more copper.

Thermal models help to illustrate this concept. The models below

show the influence increased copper can have on the same connec-

tor pushing the same 50A/blade through all ten power blades. The

top illustration (figure 1) shows 284.5g (10 oz) of copper, resulting in

an absolute temperature of 52.8°C based on 20°C ambient for a T-

Rise of 32°. The second illustration (figure 2) shows that by doubling

the copper on the PCB, the T-Rise of this connector is only 22°. If

one were to put airflow over this model, you would see a dramatic

decrease in temperature on both scenarios and a corresponding

increase in current you are capable of carrying through the interface.

Design in Extreme EnvironmentsFit more watts into the same or less amount of space

Nothing works without power – this also applies to electronic devices and, ultimately, the con-nectors within. There we take a look at the recent developments in power connector design to

address the ever increasing needs of high-end server and storage applications but also meetingthe demands of pioneering industries exploring the use of renewable energies.

By Herbert Endres, Molex

Figure 1: 50A over 10 contacts with 283.5g (10 oz) copper PCB �contact +52.8°C @ 20°C ambient

D E S I G N & S I M U L A T I O N

45www.bodospower.com October 2009 Bodo´s Power Systems®

That begs the question; why is the connector height so important?

The answer is simple; less height means more airflow, and more air-

flow keeps the connector interface cooler and increases the current

carrying capacity at a typical 30° T-Rise. Airflow is being factored

more and more into the thermal design of new systems.

As a rule of thumb, every 100W of power needed to power the sys-

tem silicon, 50 additional watts are needed to cool the system from

the heat generated. So, if system architects and thermal manage-

ment engineers can allow heat to escape more freely and effectively,

the power needed to actually cool the system can be reduced –

hence, less power consumption.

Two members of the Molex EXTreme Power family that are excellent

examples of more power capacity and low profile packaging are:

EXTreme LPHPower™ – a low profile, hybrid connector capable of

127A/25mm at just 7.50mm height above the PCB. It is available in

both coplanar and right-angle mounting options.

EXTreme Ten50Power™ – a 10mm high 50A/blade connector sys-

tem that sets new standards for current density and is available in

coplanar and right-angle configurations with or without signal con-

tacts.

The chart in figure 3 is a guide to

Molex EXTreme Power products

– all are evidence of our dedica-

tion to our focus on customer

needs and to providing the widest

range of power supply intercon-

nect solutions available.

Future-proofing system design by

allowing for next-generation

power is a key element in con-

nector selection. Power integrity

is the vehicle with which design-

ers can use to make the right

choice, and Molex is the power

interconnect company that can

provide the innovative solutions

needed to achieve these chal-

lenging system design goals.

www.molex.com

Figure 2: 50A over 10 contacts with 567g (20 oz) copper PCB � con-tact +42.5°C @ 20°C ambient

Figure 3: Molex EXTreme Power Product Roadmap

www.we-online.com

E M C C O M P O N E N T S

I N D U C T O R S

T R A N S F O R M E R S

R F C O M P O N E N T S

P O W E R E L E M E N T S

C O N N E C T O R S

C I R C U I T P R O T E C T I O N

S W I T C H E S

A S S E M B LY T E C H N I Q U E

Eco TransformerTransformer for energy saving electronic devices

Universal input voltage: 85-265 VAC

Samples free of charge

4kV isolation voltage

Guaranteed in stock

High efficiency

Reference design of all major IC manufacturers

46 Bodo´s Power Systems® October 2009 www.bodospower.com

N E W P R O D U C T S

Pressurex® film from Sensor Products Inc. is a quick, accurate and

economical way to detect and correct pressure variations in the lami-

nation of dry film resist to the board substrate. When placed between

nip rollers in the lamination press, the film instantaneously and per-

manently changes color directly proportional to the actual pressure

applied.

With Pressurex®, variations in pressure that can lead to defects are

easily detected and corrected—decreasing scrap, improving yield,

and increasing productivity.

Even, consistent bonding of the thin layer of photoresist is critical to

the board’s subsequent electrical performance. The photoresist mate-

rial is placed on the board’s surface using a hot roller system. If the

rollers do not exert uniform pressure across the board’s surface, the

thin photoresist layer can fail to adhere, bubble or even wrinkle dur-

ing the process. This causes electrical instability and possible failure

of the resulting board.

For a free sample, contact Sensor Products Inc. at

1.973.884.1755 (USA),

email info@sensorprod.com or visit their website.

www.sensorprod.com/sample

Reduce Dry Film Resist Lamination Defects

Linear Technology Corporation introduces

the LTM4614, a complete dual DC/DC

μModule® regulator system including induc-

tors in a tiny surface mount package. The

LTM4614 can regulate either two voltages

from 0.8V to 5V at up to 4A each or one out-

put voltage at up to 8A by sharing current

from both outputs. The LTM4614’s versatility

is enhanced by its ability to operate from two

different supply rails ranging from 2.375V to

5.5V (6V max) or from one input supply by

tying the input pins together. This complete

DC/DC system solution includes all the ele-

ments needed for a dual point-of-load regu-

lator: inductors, capacitors, DC/DC con-

troller, compensation circuitry and power

switches.

www.linear.com

Dual 4A or Single 8A DC/DC μModule Regulator

Watlow®, a designer and manufacturer of

electric heaters, controllers and temperature

sensors, introduces the EZ-ZONE® PM

Express panel mount controller. The EZ-

ZONE PM Express fills the need for a PID

controller delivering advanced control func-

tionality while having a basic user interface.

It also extends the breadth of the EZ-ZONE

PM family without compromising tuning and

control performance.

The EZ-ZONE PM Express controller fea-

tures a friendly user interface supported by

two menus and a streamlined list of parame-

ters making the product ideally suited for

basic applications and user levels. The

Express menu eliminates complexity and

reduces training costs and user errors. The

EZ-ZONE PM Express controller comes

complete with PID auto-tune for fast, effi-

cient startup. Standard bus communications

provide easy product configuration via PC

communications with EZ-ZONE .

www.watlow.com

The EZ-ZONE® PM Express Panel Mount Controller

IMEC presented a host of new partners with-

in its Silicon Solar Cell Industrial Affiliation

program (IIAP). Among these are MEMC

Electronic Materials Inc., Leybold Optics

Dresden GmbH, Roth & Rau AG and

Mallinckrodt Baker B.V.

IMEC's recently launched IIAP is a multi-

partner, private-public R&D program set up

to accelerate the development of crystalline

silicon solar cells that will lower production

cost and cut the amount of silicon per watt in

half. The initiative targets efficiencies of

about 20 percent by exploring both wafer-

based bulk-silicon and epitaxial cells.

With this ambitious but realistic goal, IMEC

brings together silicon solar cell manufactur-

ers, as well as equipment and material sup-

pliers, based on a strong partnership of

sharing talent, risk and cost, intellectual

property and creating new opportunities for

proprietary IP within the program.

www.imec.be

Promotion of PV Industrial Affiliation Program

47www.bodospower.com October 2009 Bodo´s Power Systems®

N E W P R O D U C T S

National Semiconductor introduced the industry’s smallest white light-

emitting diode (LED) driver with dynamic display backlight control.

The LM3530, a member of National’s PowerWise® energy-efficient

product family, drives up to 11 high-current LEDs in series, illuminat-

ing larger displays in portable media devices such as smartphones.

The LM3530 is offered in a 12-bump micro SMD package measuring

just 1.615 mm × 1.215 mm × 0.425 mm.

Today’s increased multimedia content in portable devices is fueling

the trend towards larger displays and longer video playback, which

require more power. National’s LM3530 LED driver employs sophisti-

cated ambient light-sensing algorithms and content-adjustable back-

lighting to optimize the display, realizing up to a 55 percent power

saving over the common practice of driving the backlight at a con-

stant brightness.

http://www.national.com/led

White LED Driver with Dynamic Backlight Control Reduces Power Consumption

Designed for accuracy and economy, the

new Model DR217 Series Radial Leaded

Inductors from Datatronic Distribution, Inc.,

combine superior performance, reliability and

long-life.

The ROHS compliant DR217 Radial Leaded

Inductors provide superior protection against

challenging EMI/RFI problems in current

handling applications up to 8.4 Amps. The

proven, affordable DR217 Series offers

extended life in temperatures ranging from -

20 to +80°C.

The DR217 series is designed for EMI filters

and switching power supplies. Combining

durability with high performance, the DR217

series is ideal for commercial and industrial

equipment including computers, telecom

equipment, power supplies, industrial

machinery, factory automation equipment,

instrumentation and more.

Depending on the specific model, the DR217

Series Inductors feature an inductance

range from 1.0ìH to 150 mH. The DCR is

specified from 0.008 to 520 Ohms maximum

over a maximum current rating from 8.4 to

0.045 Amps. The DR217-0 through DR217-

7 Series have minimum Q specifications

based on test frequencies from 25.2 kHz to

7.96 MHz.

With their through-hole wirewound coil

design, the DR217 Series Inductors come in

round packages sized from 0.196 inch (5.0

mm) diameter to 0.551 inch (14.0 mm) diam-

eter, with lead spacing from 0.78 inch (2.0

mm) to 0.295 inch (7.5 mm) depending on

the specific model. They are compatible

with high-speed assembly equipment, and

they are suitable for high-temperature sol-

dering. Tinned leads with leaded solder are

also available.

Model DR217 Series Inductors are priced

from $0.075 to $0.22 each in typical produc-

tion volumes. Lead-time is 6 to 8 weeks.

Volume OEM pricing is available upon

request. Custom designed DR217 Series

Radial Leaded Inductors can be specified to

meet unique circuit requirements.

Datatronic Distribution, Inc., manufactures

custom and standard transformers, induc-

tors, ADSL transformers, LAN filter modules

and many other magnetic devices.

For more information, contact Datatronic Dis-

tribution Inc., 28151 Highway 74, Romoland,

CA 92585, or 951-928-7700, or fax 951-928-

7701, or email at ddisales@datatronics.com,

or visit the website.

www.datatronics.com

Economical Radial Leaded Inductors Deliver EMI/RFI Protection

KOA is delighted to introduce the new LT73V thermal sensor. The product is targeting the Automotive

market, with its thin film technology providing high accuracy at low cost. The LT73V also guarantees high

reliability and stability over time.

This PTC is available in sizes 0805 and 1206 (metric: 2012 and 3216). The resistance ranges are avail-

able from 51 Ohm up to 22 kOhm, with tolerances of 2% or 5%. A wide variety of temperature coeffi-

cients are available, starting at 150 ppm/K and going up to 4500 ppm/K, with a TCR tolerance down to

10%.

The operating temperature ranges from -55°C up to +155°C. The LT73V fully complies with EU RoHS

and China RoHS requirements, and is suitable for wave and reflow soldering.

www.koaeurope.de

Thermal Sensor for Automotive Market

48 Bodo´s Power Systems® October 2009 www.bodospower.com

N E W P R O D U C T S

ABB France 19

ABB semi C3

Bicron 43

Cirrus 7

CT-Concepts C2+13

CUI 33

Danfoss 17

Hyline 15

Infineon 13

Intersil 5

IR C4

ITPR 37

IXYS 23

LEM 1

National 3

PE Moscow 41

PEM UK 27

Powersem 9

Productronica 25

Semikron 11

SPS/ICP/DRIVES 35

VMI 29

Würth Elektronik 45

ADVERTISING INDEX

Würth Elektronik has released a new catalogue for Assembly Tech-

nique, Power Elements and the new product range Switches.

Switches:

The new product range of Würth Elektronik, WE-Switch, includes dif-

ferent types:

2.54mm THT Horizontal Dip Switch

2.54mm THT Right Angle Type Dip Switch

2.54mm THT & SMD Piano Type Dip Switch

2.54mm THT & SMD IC Type Dip Switch

2.54mm & 1.27mm SMD Half Pitch Dip Switch

Assembly Technique:

There are different types of WEAssembly products available: from

Spacers Studs and Cable Holders to Heat Shrink Tubes.

Power Elements:

To get a high current on the PCB

(10A/Pin) the Power Elements of

Würth Elektronik, are an alternative

for soldering. Würth Elektronik

Power Elements are a safe connec-

tion to PCB with no thermal burden!

All products are available ex stock.

Samples are free of charge. Würth

Elektronik offers several Design Kits

with free refills.

New Catalogue for Electromechanical Components

Toshiba Electronics Europe has expanded its family of miniature pho-

tocouplers with a range of devices that incorporate two switching

channels in a single SO-8 package measuring just 5mm x 4mm. The

new TLP21xx devices will significantly simplify the design and reduce

the component count of applications requiring high-performance

switching and optical isolation. They can also reduce PCB area by

approximately 40% when compared with designs based on single-

channel devices.

The TLP2105 and TLP2108 offer buffer and inverter logic outputs

respectively, operate over a wide 4.5V to 20V supply voltage, and

can be used in applications requiring typical data rates to 5Mbps.

All of the devices have a rated isolation voltage of 2500Vrms and are

guaranteed for performance across an extended -40ºC to 100ºC

temperature range.

www.toshiba-components.com

Dual-Channel Photocouplers Offer PCB Space Savings of 40%

Intersil Corporation (NASDAQ Global Select: ISIL), a world leader in

the design and manufacture of high-performance analog and mixed-

signal semiconductors, announced the ISL28207, the first in a family

of operational amplifiers built using the company’s new proprietary

bipolar process technology.

Intersil’s ISL28207 is a dual 40V low-power bipolar precision opera-

tional amplifier that exhibits outstanding DC precision and superb

temperature drift performance. The device offers a low offset volt-

age of 75 micro-V max and a typical input bias current of 60pA.

Temperature drift is only 0.65 micro-V/degree C max for input offset

voltage and 0.2pA/degree C for input bias current, making it ideal for

16- and 24-bit applications. The ISL28207 exhibits a wide operating

voltage range of 4.5V to 40V and an operating temperature range of

-40 to +125 degrees C.

www.intersil.com

High-Voltage PicoAmpere Input Precision Operational Amplifiers

www.we-online.com

Let there be light

ABB Switzerland Ltd SemiconductorsTel: +41 58 586 1419www.abb.com/semiconductors

Power and productivityfor a better world™

Economicallywith ABBsemiconductors

Part Number Package VOFFSET

VOUT

IO+ & IO-

(typical)

tON

& tOFF

(typical)

AUIRS2123S SOIC8 600V 10V - 20V 500mA 140 ns & 140 ns

AUIRS2124S SOIC8 600V 10V - 20V 500mA 140 ns & 140 ns

The AUIRS212xS family of 600V, single

channel high-side driver ICs for low-,

mid-, and high-voltage automotive

applications features exceptional

negative Vs immunity to deliver the

ruggedness and reliability essential for

harsh environments and automotive

under-the-hood applications.

Features

• Designed and characterized to be

tolerant to repetitive Vs transient

voltage

• Fully operational up to 600V

• Tolerant to large dV/ dt

• Under voltage lockout

• Lead-free, RoHS compliant

• Automotive qualified per AEC-Q100

t

VS Undershoot

VS -COM

-VS

VBUS

Greater protectionagainst a “negative Vs” event

t

Rugged, Reliable

Automotive-Qualified 600V ICs

THE POWER MANAGEMENT LEADER

For more information call +33 (0) 1 64 86 49 53 or +49 (0) 6102 884 311

or visit us at www.irf.com

10388AD_AUIR2123_BODOS_v1.indd 1 28/01/2009 16:40