NE_22_11_20 by Hiba Dweib

www.newelectronics.co.uk

visit www.newelectronics.co.uk/forum and join the discussion

22 November 2011

ENGINEERING DESIGN SHOW 2012 LAUNCHES — SEE PAGE 14 FOR PREVIEW

One MAC, many PHYs

Edgar: “Wi-Fi is exploding into new markets; if there’s spectrum available, Wi-Fi should have it.”

18,000 price reductions on the parts you need. FIND IT. DESIGN IT. BUY IT AT RSWWW.COM

Contents Vol 44 No 21

Better by design

Findlay Media launches the Engineering Design Show to fill an obvious gap in the market Cover Story

One MAC, many PHYs 14

With Wi-Fi ‘exploding’ into new market areas, the technology is taking advantage of more parts of the spectrum Contract Manufacturing

Bouncing back

After years of offshoring, the UK’s contract electronics manufacturers are seeing strong order books Analogue Design

Charging ahead 7

Getting on the bus

How a general purpose oscilloscope can help with debugging designs featuring a low speed serial bus Communications Hardware

Quality networking

A UK start up has developed a way of ensuring quality of service on congested networks Backplanes & Boards

On the platform

A newly introduced VPX development platform provides a basic environment for software and board integration Marketwatch 26

New Electronics’ monthly round up of component pricing

We explore the world of serial communications, including the latest USB specification and Thunderbolt

Power to the people

www.newelectronics.co.uk

Despite holding great promise as a battery replacement technology, fuel cells have yet to make a breakthrough

Comment

Are safety critical systems not as safe as we imagine? 7

Gallium nitride project aims to boost power efficiency Mixed signal asic supply chain enhanced Intel’s 4004 microprocessor turns 40 Engineering design in the UK is alive and kicking, according to a roundtable panel

Technology Watch

A long running serial

Got a problem? See if the Forum can help you solve it

News

Electric vehicle batteries must be managed carefully in order to provide the desired lifetime and charge cycles Embedded Test

www.newelectronics.co.uk/forum

Photo: Charlie Milligan

Engineering Design Show

Readers using the digital edition can access further information by clicking on these links Further information White papers Videos

22 November 2011

It’s only natural to want the best.

Power Supplies for Defence and Aerospace

roband

Quite unique in this day and age Roband Electronics plc Charlwood Works • Charlwood • Horley • Surrey • RH6 0BU • England Tel. 01293 843000 • Fax. 01293 843001 email. postmaster@roband.co.uk

www.roband.co.uk

Comment

www.newelectronics.co.uk/forum Your electronics community discussion board Group Editor: Graham Pitcher Web Editor: Chris Shaw Deputy Web Editor: Laura Hopperton Contributing Editors: David Boothroyd, Chris Edwards, Louise Joselyn, Roy Rubenstein Art Editor: Martin Cherry Illustrator: Phil Holmes Key Account Director: Tricia Bodsworth Classified Sales: James Slade Circulation Manager: Chris Jones (circulation@findlay.co.uk) Production Controller: Nicki McKenna Publisher: Peter Ring Executive Director: Ed Tranter Represented in Japan by: Shinano International: Kazuhiko Tanaka, Akasaka Kyowa Bldg, 1-6-14 Akasaka, Minato-Ku, Tokyo 107-0052 Tel: +81(0)3 3584 6420 New Electronics: Tel: 01322 221144 Fax: 01322 221188 www.newelectronics.co.uk email: ne@findlay.co.uk

ISSN 0047-9624 New Electronics, incorporating Electronic Equipment News and Electronics News, is published twice monthly by Findlay Media Ltd, Hawley Mill, Hawley Road, Dartford, Kent, DA2 7TJ Copyright 2011 Findlay Media. Annual subscription (22 issues) for readers in the UK is £106, overseas is £161, and airmail is £197. Origination by CTT, Walthamstow, London E17 6BU Printed in England by Wyndeham Heron Ltd, Heybridge, CM9 4NW

Moving on? If you change jobs or your company moves, please contact circulation@findlay.co.uk to continue receiving your free copy of New Electronics

www.newelectronics.co.uk

Not fit for purpose? Is the software written for safety critical systems not up to scratch?

t is an accepted fact that electronics and, by association, software have pervaded our lives. And we can assume that the vast majority of safety systems today are based on some form of electronic control. So it is a bit worrying to hear an independent safety consultant claim that most critical software has been built ‘using methods that aren’t fit for purpose’. The consultant is particularly scathing regarding the use of C as the de facto programming language. He believes C is weak and, by implication, has no role in safety critical software. In fact, he is not entirely complementary when it comes to MISRA C, the variant used by the auto industry, among others, to bring more stringency to bear. But his criticisms move beyond C to address the whole approach to the question of safety critical system development. He despairs, for example, at the decline in the use of the formation specification. He also sees weaknesses in the way in which systems are defined; in his opinion, the way boundaries are drawn are defective. When systems are defined, he contends, people forget there will be users and those users will be inside the system. So we have to ask whether things are as bleak as they appear. The answer has to be no, although the points made are important. In the opinion of the Safety Critical Software Club, ‘there aren’t as many accidents as there used to be, because we can do lots of things to avoid problems’. But the Club admits, despite all this, accidents still happen. And accidents happen not only because systems are becoming increasingly complex, but also because of the interactions with other systems and with people. Exploring every possibility is out of the question, but it is incumbent upon engineers to use every possible tool available to them and that includes using a language like SPARK, instead of C. Graham Pitcher, Group Editor (gpitcher@findlay.co.uk)

22 November 2011

Safe t y Cr iti cal So f t war e News

Power electronics efficiency targeted

Accidents will happen More could be done to make critical systems safer, says an industry expert. Graham Pitcher reports.

photo: FBH/schurian.com

Over the next three years, the EU HiPoSwitch project will focus on developing GaN based transistors, which the team believes are key to bringing increased power conversion efficiency. The researchers believe GaN transistors will enable higher frequencies without major switching losses, due to the lower Rds(on) of GaN power transistors, combined with reduced input and output capacitances. The project will develop vertical GaN power transistors, with work undertaken by German research institute FBH and Infineon Technologies.

Why aren’t there more accidents? That question was posed at a recent meeting of the Safety Critical Systems Club (SCSC) by Professor Tom Anderson from Newcastle University’s Centre for Software Reliability. “Are we lucky?,” he asked. “There aren’t as many accidents as there used to be, because we can do lots of things to avoid problems. But, despite all this, accidents still happen.” There are many reasons why accidents continue, including increasing system complexity and the fact that digital systems can be compromised. “But there is also interaction between systems and interaction between people and systems,” he noted. Martyn Thomas, an independent consultant, was more aggressive with his personal view of safety critical systems design. “Most critical software has been built using methods that aren’t fit for purpose,”

Intel’s 4004 turns 40

Parallel programming standard launched Looking to make it easier for programmers to take advantage of parallel computing, a group of interested companies has launched the OpenACC standard. Initially developed by PGI, Cray and NVIDIA, with support from CAPS, OpenACC is designed to allow scientific and technical programmers to take advantage of the power of heterogeneous cpu/gpu computing systems, particularly in supercomputers. OpenACC allows parallel programmers to provide simple hints – known as ‘directives’ – to the compiler, identifying which areas of code to accelerate, without requiring programmers to modify or adapt the underlying code itself. By exposing parallelism, directives allow the compiler to do the detailed work of mapping the computation onto the accelerator. According to the companies, developers have reported application performance increases of up to an order of magnitude over existing approaches. www.openacc-standard.org • For more on exascale computing, see the 13 December issue

www.newelectronics.co.uk

he said, adding that industry hasn’t learned the lessons of the last 40 years. “One of the basic lessons has been the importance of type safety in computer languages, where a strong structure of data types meant tools could tell if you had made a mistake. Yet you will still find type errors,” he contended. His wrath is focused on C. “C rejoices in a weak underlying type framework, which is why you get buffer overflows. C can’t tell the difference between a pointer and a variable and there’s no protection for the programmer who makes a trivial mistake,” he believed. Thomas says the solution is ‘industrial strength’ languages and tools, such as SPARK, the subset of ADA recommended by SCSC. “There are promising developments, including F#, but how do you stop people writing software in C?” www.scsc.org.uk

It’s 40 years since the first microprocessor hit the market. Intel’s 4004 boasted 2300 transistors and ran at 740kHz. Manufactured using a 10µm silicon gate enhancement load pMOS technology, the chip could handle 92,000 instructions per second. The device was designed by Intel engineers Federico Faggin, who would go on to set up Zilog, and Ted Hoff.

High quality graphics for mobiles

ASIC design service expands

The latest gpu from ARM, the Mali-T658, will enable Playstation 3 quality graphics on smartphones and tablets. Peter Hutton, general manager of ARM’s media processing division, said: “Next generation consumer devices based on the Mali-T658 gpu will address the growing user expectation for slick user interfaces and desktop class graphics.” Mali-T658 offers four times performance of the Mali-T604, something which ARM believes will open new markets, such as computational photography, image processing and augmented reality. www.arm.com

There remains significant demand for asics, according to GJ Davids, chief executive of asic supply chain specialist EquipIC, but industry changes make it harder for small companies to benefit. Looking to meet increasing demand, EquipIC has extended its supply chain by signing a deal with US based Perceptia Devices, a mixed signal chip design specialist with expertise in rf and analogue design at less than 90nm. A further agreement has been reached with Delft based mixed signal specialist SystematIC Design. www.equipic.com

22 November 2011

News Start U p S u p p o rt

Briefs Smaller, thinner power SoC Enpirion has expanded its power ic portfolio targeted with the EN5339, a 3A power SoC that integrates the controller, power mosfets, compensation network and inductor. The device is 20% smaller and 40% lower than previous 3A parts from the company. Switching at 3.5MHz, the EN5339 is said to have an efficiency of 95%. www.enpirion.com

UK EMS company beats China to deal United EMS has won a £3million manufacturing contract for a high volume electronics product, beating competition from China. United EMS director Tony McFadden said: “This is a great story for the UK electronics industry and something we should all be proud of. Working in partnership with a UK distributor and by using an innovative approach, we have managed to beat Asian competition and bring a major manufacturing contract back to the UK.” Anglia Components has won a £1m supply contract as part of the deal. • For more on contract manufacturing in the UK, see p22 of this issue

Power drive launched Amantys has launched the Power Drive, a high isolation gate drive for medium and high voltage applications. The device is said to feature intelligence, improved reliability and better performance.

www.amantys.com • For more, see the 13 December issue

Innovation incubation Academy set to help bring innovative ideas to market. Graham Pitcher reports. The recent global financial crisis, combined with a maturing industry, means venture capital funds are not as interested in the electronics sector as they used to be. The result is that good ideas aren’t getting developed. The European Microelectronics Academy (EMA) is looking to break through this apparent barrier by bringing together a range of people and organisations to help start ups get off the ground. EMA chairman Chris Smart, left, Adrian Buckley from Mentor One of the founders is Mentor Graphics, Graphics and Peter Claydon, cto of Continuum Bridge which established Cre8 Ventures in 2005 as a way of helping start ups to grow. While Cre8 was a Mentor vehicle, EMA has a wider vision. Adrian Buckley, Mentor’s area director for North and West Europe, said: “By setting up an independent company, we are avoiding conflicts of interest.” Cre8 helped start ups with finding funding and connecting with customers. Chris Smart, EMA chairman, added: “Taking this model further brings the benefit of supply chain collaboration; it’s easier if there’s an independent organisation with a range of partners.” EMA, whose ceo is Cre8 Ventures founder Carson Bradbury, is driven by a steering group of experienced electronics industry managers, each with a network of useful contacts. Opportunities exist for so called ‘blue chip partners’, who can join the organisation by paying a membership fee. Start ups accepted by EMA will have free of charge access to help. “Our intention,” Smart added, “is to have key industrial partners in areas such as IP and foundry, providing start ups with a ‘one stop shop’.” One of EMA’s aims is to have created a billion dollar company within the next decade. Although early stage investor NESTA – the National Endowment for Science, Technology and the Arts – is a partner, EMA is not starting out as an equity provider. Rather, it hopes to point companies in the right direction and to make them attractive to investors. One company already working within the EMA framework is Continuum Bridge, recently set up by picoChip founder Pete Claydon. The company is looking to develop technology that links service providers with consumers. “Our challenge,” said Claydon, “is to engage with service providers and we are being linked with them by the EMA network. We anticipate some of our funding will come from service providers, rather than from VCs.” Buckley noted: “If your customer is producing electronics, then networking is straightforward. But if it’s, for example, the NHS, EMA can help to connect start ups to the right people more effectively and that’s something they find difficult.” www.emanetworks.com

ADVANCED NAND TECHNOLOGY FROM TOSHIBA As demand for memory becomes more focused on higher densities, single packages and smaller chip sizes, you need cutting edge, reliable technology from the industry leaders. Toshiba’s line up of MLC NAND products includes the world’s first 32nm 128GB e•MMC™. These embedded NAND flash multichip BGA packaged memories with an integrated controller minimise development and ease integration into system designs. For industrial applications requiring increased endurance in longer product life cycles, our SLC NAND products are available with capacities up to 64Gbit in 43nm. And, our advanced process technology innovations mean that we will soon be introducing 32nm SLC NAND and 24nm MLC NAND based e•MMC™. For further information on our complete range of NAND technology, visit www.toshiba-components.com/memory

Advanced Portable System Power Management ICs Quad Output PMIC with HyperLight Load™ DC/DC, 3 LDOs and I2C Control Applications

MIC2826 '9,1

9 %DWWHU\

'& '&

) /'2 ,1 ) /'2 ,1

/'2

)

/'2

HOST PLATFORM PROCESSOR

(1 6'$ 6&/ ,54E ,2& &RQWURO 2YHU *36 3RZHU 6\VWHP

APPS PROCESSOR 6:

'*1'

0HPRU\

)

/'2 287 )

+RVW , 2

0RELOH $SSOLFDWLRQV

/'2 287 )

&RUH 6XSSO\

/'2 287 )

&RUH 6XSSO\

/2*,& &21752/

*36 6XEV\VWHPV

$*1'

)DVW PRGH N+] ,2& &RQWURO ,QWHUIDFH '\QDPLF 9ROWDJH 6FDOLQJ 6HTXHQFLQJ ([WUHPHO\ +LJK /LJKW /RDG (IILFLHQF\ 7LQ\ PP [ PP 0/)® 3DFNDJH

Today's a d v a n c e d p o r t a b l e e l e c t r o n i c s require highly integrated power system s o l u t i o n s f o r c o m p l e x s y s t e m p o w e r, small size, and long battery life. Micrel provides complete system power solutions, such as the MIC2826, to meet these needs. The MIC2826 integrates a single 500mA HyperLight Load™ synchronous buck (step-down) regulator with three Low Dropout Regulators in a tiny 2.5mm x 2.5mm Thin MLF ® package. The MIC2826 also features a standard 400kHz Fastmode I 2C interface that provides Dynamic Voltage Scaling (DVS), programmable power sequencing, and individual output control, making it the perfect integrated power system solution.

*HQHUDO 3XUSRVH 30,&

Ideal for use in:

Application Processors GPS Subsystems Mobile Phones/PDAs Portable Media Players General Purpose PMIC

For more information, contact your local Micrel sales representative or visit Micrel at: www. micrel.com/ad/mic2826. © 2010 Micrel, Inc. All rights reserved. Micrel and Innovation Through Technology are registered trademarks of Micrel, Inc. HyperLight Load is a trademark of Micrel, Inc. MLF is a registered trademark of Amkor Technology, Inc.

www.micrel.com

News I n d u stry Ro u n dtab le

Alive and kicking UK engineering design is in good shape, says roundtable panel. Graham Pitcher reports.

From the left: Robert Morton, Donald Blythe, moderator John Pullin, Prof Steven Crowley and Louise Hardy

Over the last couple of years, there has been widespread debate about which part of the hospital the UK’s manufacturing industry finds itself. Depending upon who you talk to, the answer ranges from intensive care to the out patients department. But a recent event suggested that UK manufacturing may actually be in the morgue. The event was the centrepiece industry roundtable at National Instruments’ NI Days, held on 9 November in London. The question the panel convened to discuss was: ‘Manufacturing is dead. Is engineering design next?’. Not surprisingly, the panel found itself unable to agree with the premise. Kicking off the discussion was Louise Hardy, infrastructure director for the Olympic Park, who also provided the keynote address for the event. Talking from an Olympic perspective, she said most of the engineering at the 2008 Beijing Olympics had been undertaken by UK companies. “That expertise is still sought globally and respected. And one of the triumphs of the 2012 Olympic design and build is that it has overwhelmingly used UK based expertise.” Robert Morton, managing director of NI UK and Ireland, took exception to the question his company had posed. “Looking at the stats, UK manufacturing output was at its highest level in 2007. While that has declined for obvious reasons, the UK is still the seventh largest manufacturer in the world. We need to promote manufacturing and celebrate it.”

Donald Blyth, chief test engineer for Selex Galileo and a late substitute, was another to believe manufacturing isn’t dead. “There’s a lot of low volume, high value manufacturing in the UK,” he believed, “and a core of knowledge in the UK supply chain.” The panellists were asked how realistic it would be to rebalance the UK’s economy in favour of manufacturing. Professor Steven Cowley, director of the UK Atomic Energy Authority’s Culham Laboratory, believed it could be done. “But the Government isn’t sure what conditions need to be put in place. We have a strong base, but what can be changed that will allow people to take a step forward? The Government needs to introduce a stimulus to help companies to be more creative.” Picking up on a recurring theme, Morton noted what he described as ‘tremendous’ research activity in UK universities. “The challenge is how to capitalise on this and bring commercial success.” He saw some stereotyping in the belief that we can invent, but we can’t commercialise. “Is this a self fulfilling prophecy?,” he wondered. Prof Cowley added: “I sit on the Council for Science and Technology, which advises the Prime Minister. He has committed to look at how we can take work undertaken by the world’s second best research nation and convert that into products and services. How can we make this work have a bigger impact?” Can engineering design be saved? Blyth noted that Selex Galileo had certainly changed. “We used to have large military contracts. Now the money is no longer there, we need to develop and build product lines for the market. That needs particular skills within R&D; we have to be efficient and show a return on investment.” Morton returned to the celebration theme. “We celebrate celebrity too much,” he claimed. “People don’t say they want to be an engineer and we need to get children excited about the prospects. Children are inquisitive and want to understand how things work, but the education system takes that out of them.” Prof Cowley believed that apprenticeships are a key way of bringing people into engineering. “We launched our apprenticeship programme six years ago and it’s been very successful.” How can people be persuaded to follow a career in engineering? Hardy said that money was one issue. “While a lot of people become engineers because it’s a vocation, we need to enthuse young people about the opportunities.” Prof Cowley noted: “We need to take the fact that we’re at the leading edge of design and use that to keep interest in engineering going.” The roundtable closed with panel members being asked who their engineering hero was: apart from James Dyson, no modern engineer was mentioned. Perhaps that shows the scale of the problem.

Standard and factory modiﬁed plastic, extruded uded ed and die-cast aluminium m enclosures. • machined • printed • drilled • custom colours

01256 812812 2 • sales@hammondmfg.eu sa sales@hammo sales ees@ esss@ @h ham amm mon nd d • www.hammondmfg.com ammond am mm m mondmfg mfg.com mfg. g.co coom m 10

22 November 2011

www.newelectronics.co.uk

LabVIEW 2011 Now Available

Name Dr. Laurel Watts Job Title Principal Software Engineer Area of Expertise Chemical Engineering LabVIEW Helped Me Control multiple instruments operating in harsh conditions Latest Project Engineer the ultimate storm chaser

NI LabVIEW

LabVIEW makes me better because the

with hardware is so seamless

01635 517300 >>

Find out how LabVIEW can make you better at ni.com/labview/better

uk.ni.com info.uk@ni.com

NEW: LabVIEW 2011 now released. Find out more at ni.com/labview/whatsnew JOIN THE CONVERSATION: Follow us on

Search niukie

©2011 National Instruments. All rights reserved. LabVIEW, National Instruments, NI, and ni.com are trademarks of National Instruments. Other product and company names listed are trademarks or trade names of their respective companies. 2785

www.newelectronics.co.uk

www.newelectronics.co.uk/forum here are some live forum topics. do you have an answer? • ASIC/SoC/FPGA Is self gating a useful low power technique? • EDA/Board Level Design Molex alternatives? Any suggestions appreciated. • Embedded Software Development What is the difference please between C & Embedded C? • Legislation RoHS Recast - monitoring and control instruments. • Micros I need to interface a spansion flash memory with an nxp P89V51RD2 using spi protocol. • Mixed Signal & Analogue I need to use a polyresistor to design a 12bit voltage mode output DAC based on R-2R structure. • Power Voltage dips in flash drive query. • Test & Measurement When using an MSO 7104A is it possible to capture the Quick Measurement info when saving info on the screen? • Other Technologies Long range Ethernet cable needed.

newelectronics

The site for electronics design engineers

Most popular News

Technology

Supercomputer simulates H1N1 virus

Researchers have achieved a major breakthrough in the battle against the H1N1 influenza virus with the aid of a gpu accelerated supercomputer. A team from the Institute of Process Engineering of Chinese Academy of Sciences (CAS-IPE) is using Nvidia Tesla gpus to create the world's first computer simulation of a whole H1N1 influenza virus at the atomic level.

Findlay Media launches Engineering Design Show

New Electronics' parent company, Findlay Media has announced the launch of The Engineering Design Show. Taking place on October 10th and 11th 2012 at the Jaguar Exhibition Hall at the Ricoh Arena, Coventry, the Show will focus on the needs of design engineers in the mechanical and electronic fields and will include a comprehensive conference and workshop programme.

Ultrabooks to take on tablets?

Shipments of the new ultrabook platform could account for more than 40% of all notebooks by 2015, as the mobile pc market aims to stave off the rising competitive threat of tablets.

22 November 2011

Could implantable electronics revolutionise the healthcare industry?

Despite the challenges of designing for environments that are typically inhospitable to conventional electronics, research teams from around the world are developing novel methods for the continuous, real time monitoring and sensing of a range of chronic diseases.

UK graphene research leading the field

The UK is setting the pace in the race to develop and commercialise graphene and this lead looks set to continue with Chancellor George Osborne pledging £50million for a 'Global Research and Technology Hub'.

Faster than the speed of light?

At just over 186,000m/s, the speed of light (the 'C' in Einstein's E=MC2) plays a fundamental role in nearly every aspect of physics. Since HG Wells published The Time Machine in 1895, the idea of exceeding the speed of light and entering the realms of time travel, has been one that has consistently captured the public imagination.

www.newelectronics.co.uk

sotluttion n. 1. The act of solving a problem 5* T )JHI #BZ -&% -JHIUJOH Solution

There’s real value in working with a company that understands your system challenges. Check out TI’s cooler, intelligent High Bay LED Lighting Solution that delivers the greatest power efﬁciency, power factor correction, and the ﬂexibility to control multiple strings from a single architecture.

MachXO2™ PLD™

MACHXO2. DO-IT-ALL DEVICES DEMAND A DO-IT-ALL PLD. With the MachXO2 PLD family, you now have everything you need to meet your low power, small form factor, high functionality and low price requirements for your next consumer or system design. Access free reference designs and software, development kits and more information at: www.msc-ge.com

Web Quick Link

en/5800-www

Key Products: t 6$$ o Active PFC LED Power Controller t 514 o Resonant Switching LED Driver Controller t -. )7 o Constant Current Buck LED Driver

Visit our ToolGuide-Webshop: www.msc-toolguide.com

Free sample kit available at www.ti.com/highbayled

V-11_2010-GY-5316

5FYBT *OTUSVNFOUT BOE /BUJPOBM 4FNJDPOEVDUPS %FMJWFSJOH .03& 5PHFUIFS Brighton Shaftesbury Court, 95Ditchling Road Brighton, Sussex. BN1 4ST Tel. 01273 622446 Fax 01273 622533 Brighton@msc-ge.com

Milton Keynes 2, The Stocks, Cosgrove, Milton Keynes, Bucks. MK19 7JD Tel. 01908 263999 Fax 01908 263 003 Miltonkeynes@msc-ge.com

Weybridge Lock House, Hamm Moor Lane Weybridge, Surrey. KT15 2SF Tel. 01932 268990 Fax 01932 848610 Weybridge@msc-ge.com

Better by Design Responding to unmet demand, Findlay Media launches the Engineering Design Show. Eureka’s editor Paul Fanning explains the rationale behind this exciting new event.

he increasing imperative is for engineers to operate across a variety of technological sectors and to incorporate ever more advanced technology into their designs – and this makes getting to grips with the latest products and techniques crucial. Yet, despite the fact that there are more than 100,000 design engineers working in the electronics, electromechanical and engineering disciplines at almost 13,000 sites across the UK, there is no standalone exhibition or industry event designed specifically to meet their needs for information, advice and – above all – innovation. This seems strange, particularly at a time when it has never been more important for design engineers to have access to the latest information, advice and technological developments. Alongside this, of course, growing constraints on the time available to engineers have made it increasingly difficult for them to attend exhibitions as a whole. And, if those exhibitions focus purely on one technology or market sector, justifying that time can be even more difficult. As time becomes more precious to each design engineer, so the need for a single show that runs the technological gamut under one roof would appear to have become more pressing. This has been borne out by research undertaken by New Electronics and Eureka magazines in July 2011. A significant sample of the two magazines’ audiences was surveyed to identify the potential for an event focused on engineering design. Of the 600 interviews carried out, 68% of New Electronics

22 November 2011

readers and 75% of Eureka readers said they would be interested in attending an exhibition and conference focused on design engineering. Armed with this information, New Electronics’ parent company Findlay Media has decided to fill this longstanding gap and has launched The Engineering Design Show, which will take place on 10 and 11 October 2012 at the Jaguar Exhibition Hall, Ricoh Arena, Coventry. The show will feature a high level conference, 24 practical and informative workshops and will feature the brightest and the best in UK engineering. Findlay’s stable of magazines, including New Electronics, Eureka and Automotive Design Europe, demonstrate the company’s commitment to excellence in engineering design and reflect its credibility in the sector. Bringing this knowledge to bear in the form of a comprehensive trade exhibition seems the logical next step. According to Ed Tranter, Findlay Media’s executive director: “The research simply confirmed for us that The Engineering Design Show will offer something unique and valued in the market: an exhibition catering specifically for design engineers, regardless of the industry in which they work.” The surveys of New Electronics and Eureka readers reinforced the belief that content addressing specific topics at the event is important. The Engineering Design Show will feature two workshop theatres and a conference area with up to 36 sessions across the two days. Clearly, there is no shortage of subjects to be covered and the conference

www.newelectronics.co.uk

Preview Engineering Design Show 2012

will include topics of direct relevance to the modern design engineer, with sessions led by experts in their technological fields. Conference content will be guided by the results of July’s reader surveys and by further research, which is already underway. Topics relevant to electronics design engineers that will be offered at the conference include: test and measurement; sensors and signal conditioning; displays and optoelectronics; embedded software development; mixed signal and analogue design; wireless communications; fpgas; and powering portable products. There will also be sessions addressing designing for the aerospace, defence, automotive and medical sectors. Tranter noted: “A good conference programme is one of the keys to a successful exhibition. We realise that we need to offer visitors more than just an exhibition; we have to give them technical content that is tailored specifically to their professional needs as design engineers.” More details of the conference and workshop sessions will be provided over the coming months. Access to the conference theatre will carry a small delegate fee and tickets will need to be purchased in advance. Meanwhile, each workshop theatre will offer visitors practical, hands on content, with case study presentations by leading technology experts. This area will be free for visitors to attend and each workshop session is to be promoted individually with a full synopsis of the content and what visitors can expect to learn. The conference area and seminar theatres are deliberately located within

www.newelectronics.co.uk

the exhibition hall to maximise the benefit to exhibitors. When surveyed, design engineers also stated overwhelmingly that the event’s location and the need to address specific topics were the most important elements to a successful show. Drive times have been carefully considered for the location in Coventry and the topics requested will be covered in the conference and workshops. The Ricoh Arena International Events Centre is based within a two hour drive for 75% of the population of England. It is yards from junction three of the M6 and is near an international airport and major railway stations. Its location and its 15,000m2 purpose built conference and exhibition centre makes it an ideal venue for the new event. Ultimately, however, the Engineering Design Show will stand or fall by the quality of its exhibitors (a selection of whose comments can be found on the following pages) and, of course, its visitors. By offering a showcase for leading names in the field such as National Instruments and TDK-Lambda – and by offering a comprehensive conference programme and technical workshops – The Engineering Design Show promises to deliver an event that design engineers can truly call their own. What the market says... Leading companies and industry bodies have responded positively to Engineering Design Show – and many have already signed up to exhibit. Here is what some of them have to say about The Engineering Design Show.

22 November 2011 15

Mark Gradwell marketing communications manager National Instruments UK & Ireland “The UK has long suffered from a lack of viable, thriving live events and exhibitions for engineers, where they can learn about new technologies and techniques, get up close and hands on with the latest tools, hear about the amazing work their peers are doing, and interact with suppliers, customers and colleagues in an efficient, productive environment. National Instruments recognises the value of such events and is pleased to see Findlay Media, via its respected engineering publications New Electronics and Eureka, address this audience with its Engineering Design Show. A healthy show for industrial design engineers is something NI and many other engineering companies would welcome, both from an exhibitor and delegate perspective.”

Geoff Wilby general manager TDK-Lambda UK “We believe the Engineering Design Show is an opportunity to meet with Design Engineers and discuss with them the problems they face when deciding which is the correct power architecture for their system, each application has unique requirements cooling, size constraints, power needs etc. Throughout the show we will have our team of experienced Application Engineers who have an in depth appreciation of the best practice techniques to use when designing a system power solution. These solutions will optimise the power architecture and efficiency of the end product helping it to meet the relevant legislation requirements for the world markets. Schaeffler is looking forward to being a headline sponsor of the Engineering Design show next October. We are delighted that Findlay Media has recognised the importance of the engineering design function to the future of UK manufacturing with a targeted showcase for innovation and engineering excellence. The Schaeffler Group – including its super precision division The Barden Corporation – has always been committed to working closely with design engineers in all industrial sectors to help them to meet their specific application requirements.” Karen Preston marketing services manager Schaeffler (UK) Ltd “This show will give engineering designers the opportunity to meet experienced engineers from both Schaeffler UK and Barden on one spacious, purpose-built stand. Visitors can come along and meet the team to see how they can take full advantage of value-added, cost-effective and energy efficient solutions in their particular area of expertise. We are anticipating an exciting event in an ideal location.”

22 November 2011

Peter Brook chairman UK Electronics Alliance “The UK Electronics Alliance is delighted to support the Engineering Design Show and looks forward to this new event establishing itself as an important date in the industry calendar. Design and innovation are critical to the wellbeing of the UK electronics community, to enable the many business sectors that we support to be globally competitive and to be a key element in the revival of UK manufacturing.” Marco Pisano electronics programme manager Intellect “Design engineering is the vital and creative force of the technology industry. The future of British advanced manufacturing and electronics relies on this ‘higher value added’ service – hence we’re proud to support The Engineering Design Show. Any initiative aimed to raise the profile of UK engineering and connect designers is welcomed as we need more than ever to equip this vibrant community with the tools necessary to stay ahead of global competition”. Stephen Tetlow chief executive Institution of Mechanical Engineers “Good design goes hand in hand with good engineering – one cannot exist without the other. The Engineering Design Show is to be applauded for offering our world class design engineers the chance to enhance their knowledge and expertise.”

www.newelectronics.co.uk

Preview Engineering Design Show 2012

Stewart Goulding sales and marketing director EMS Ltd “The customer base for our products and services is very diverse and covers everything from aerospace, defence and medical devices through to optical equipment and factory automation, so we need to be able to be visible to the broadest possible audience. We feel that a comprehensive, allencompassing exhibition like the Engineering Design Show offers us that opportunity.”

Martin Partridge managing director Brownell

Paul Marshall marketing director Henkel Technologies “This conference will give design engineers a unique opportunity to meet, get hands-on training in the latest techniques and share ideas, which can only be a good thing for the industry as a whole. To have this opportunity to discuss new innovations and provide options for improved design processes across a multitude of industries is very appealing. Equally, with the pressure on designers’ time, the fact they will have put aside time to explore new options when they attend the show, creates a great starting point for exploring potential opportunities. Henkel has been involved in the design process and technical consultancy for many years and expects the show to deliver a positive forum for both the exhibitor and visitor.”

“An exhibition such as The Engineering Design Show is an ideal opportunity to broaden our coverage of this market by bringing us closer to the engineers who specify products and thereby bringing us new customers and leads and allowing us to introduce our technology to new markets.”

Ashley Evans chief executive Electronics Technology Network “In the current economic climate, the politicians and commentators are scurrying around to find the silver bullet that will resolve our fiscal woes. Recently manufacturing has been elevated, and rightly so, back to its position of importance for the UK's economy, however, design engineering is really where the UK must focus if we are really going to create wealth and jobs. Design first, the innovative products and solutions, then we can decide on the appropriate supply chain. The Engineering Design Show will be a real tonic to showcase the UK’s innovative talent.”

Matthew Aldridge bearings product director igus UK Ltd “igus UK is pleased to support the launch of the Engineering Design Show as we feel there is a demand for a high quality event that allows engineers to get hands-on with products and talk to suppliers, like us, about potential solutions and new developments in technology. We envisage demonstrating a large range of our plastic bearing and cable chain products and look forward to helping people find alternatives to traditional methods that they may be using. We feel that Findlay, through its history of publishing Eureka magazine, has the credibility to develop this event into being a must-attend for the design engineering community. We are looking forward to it already!”

www.newelectronics.co.uk

To register your interest as an attendee or an exhibitor, visit: www.engineeringdesignshow.co.uk or call Luke Webster on 01322 221144 22 November 2011 17

Cover Story Wi-Fi

One MAC, many PHYs With Wi-Fi ‘exploding’ into new markets, the technology is taking advantage of more parts of the spectrum. By Graham Pitcher.

t seems the world is unable to function without wireless communications, whatever the format. Yet only a few years ago, wireless communications was a strange world inhabited by very few people. Things have changed dramatically and the change could be put down to one person. In the mid 1980s, companies were slowly getting to grips with the concept of Ethernet. This networking technology, which first saw the light of day at the beginning of the decade, brought the ability for personal computers to pass data amongst each other at rates of up to 10Mbit/s. Yet, by the end of the 1980s, companies were looking to develop wireless communications. The first applications for the technology which was to become IEEE802.11, or Wi-Fi, were not aimed at the business environment. Instead, developers were looking to create technology which addressed point of sale systems and the like. Fig 1: How the various Wi-Fi standards relate to each other 802.11af 600Mbit/s tv white space 802.11ah 600Mbit/s <1GHz

802.11g 54Mbit/s 2.4GHz

802.11a 54Mbit/s 5GHz

802.11b 11Mbit/s 2.4GHz 802.11 2Mbit/s 2.4GHz

22 November 2011

802.11ad 6.757Gbit/s 60GHz

802.11n 600Mbit/s 2.4 and 5GHz

802.11y 3.6 to 3.65GHz

802.11ac 6.933Gbit/s 5GHz

802.11h 5.35 to 5.75GHz 802.11j 54Mbit/s 4.9GHz

Edgar: “Wi-Fi’s becoming an all encompassing technology and is starting to take share in markets that were seen as complementary – even Bluetooth.” In its early days, the technology wasn’t competitive with Ethernet: data rates were, at the most, 2Mbit/s and few applications were seen. Nevertheless, the technology developed and the first Wi-Fi standard appeared in 1997 under the guise of IEEE802.11. Still supporting no more than 2Mbit/s, the approach had three possible physical layers: infrared; frequency hopping spread spectrum; and direct sequence spread spectrum. Data was transmitted in the ISM band at 2.4GHz; something which still holds today. Earlier, there had been trials at 915MHz but, according to Richard Edgar, senior Wi-Fi product manager with CSR: “It was a very small spectrum and so it didn’t take off.” Edgar has been involved in the Wi-Fi market since 1998. “Wi-Fi was really developed to offer wireless Ethernet connection,” he recalled, “and people wanted wireless networking for their computers.” This origin can be seen in the construction of the Wi-Fi standard. “Basically, it takes an 802.3 Ethernet frame and wraps an 802.11 frame around it to transport the data,” he noted. “At the other end, the 802.11 frame is removed. It was an approach that brought users flexibility and freedom.” But one event – more accurately, one person – provided the impetus that has changed Wi-Fi from being something of a curiosity to its current status in which it is becoming pervasive. That person was Steve Jobs. Jobs had seen Wi-Fi technology developing and had decided that it should be integrated into a forthcoming product; the iMac, Apple’s ‘all in one’ desktop pc.

www.newelectronics.co.uk

IEEE802.11ac This will offer 80 and 160MHz bandwidth options, building on the 40MHz available in 802.11n. “It will support eight antennas,” said Edgar, “as well as multiuser MIMO.” With MU-MIMO, multiple stations with multiple antennas can transmit and receive simultaneously. The standard will only be available at 5GHz as there is insufficient bandwidth at 2.4GHz. “While 5GHz has lots of channels, the advantages begin to disappear as bandwidth increases,” he noted. 802.11ac will use a 64QAM constellation as standard, with 256QAM as an option. “But the error vector magnitude with 256QAM will be -32dB,” he added, “so silicon developers will have to work hard to keep the noise inside the chip down to as little as possible.” Maximum data rate is 6.933Gbit/s, but one channel in a 64QAM system will sustain 325Mbit/s. “Most smartphones can’t cope with that,” Edgar said. Contiguous and non contiguous channels are also enabled. “At 5GHz, there are things like radar and weather satellites,” Edgar pointed out. “So if a radar is operating, 11ac can’t work in that part of the spectrum. By splitting 160MHz into two 80MHz bandwidths, 11ac transmissions can have high data rates while avoiding radars.” Having said that, Edgar added there were questions about whether 160MHz channels would be deployed. Potential applications include whole home networking, where a lot of interest is being shown by consumer electronics companies. “Smartphones, networking and pcs are transitioning to 11ac,” Edgar noted, “and we may see laptops on the market in time for Christmas 2012

IEEE802.11ad “The iMac took Wi-Fi to the mass market,” Edgar noted. “The next thing you knew, all the other computer companies were putting Wi-Fi into their products; initially as an add on, but later as a standard offering. And the market has grown from there.” And what a market growth. Demand for Wi-Fi products in 1998 was worth around $2million; by 2001, that had risen to $350m and the industry hasn’t looked back. “Because Wi-Fi ‘crossed the chasm’,” Edgar commented, “it attracted new entrants; for example, Broadcom with 802.11g. But, while that brought more competition, Wi-Fi remained a pc based technology.” And that remained the case until around 2006, when the first Wi-Fi enabled phones began to appear. “Now,” said Edgar, “it’s everywhere. The world believes in Wi-Fi.” The technology has made what seems to be linear progress. “Inasmuch as 802.11a was developed before 802.11b, there is linearity,” Edgar agreed. “However, data rates have grown from 2 to 11 to 54 to 600Mbit/s.” But the developments have not come without their problems. “It took too long to develop 802.11n,” Edgar believed. “There were two industry groups and neither could get the 75% vote needed to get their technology ratified. In the end, the groups agreed to work together and most of their options got included in the spec. For instance, 802.11n offers four different methods of beam forming, yet 11n beam forming hasn’t really worked in the field.” The work done to date is about to be ‘wrapped up’ into a new baseline

www.newelectronics.co.uk

802.11ad will operate at 60GHz, which will pose technical problems. “At 60GHz, radio waves hate oxygen,” Edgar pointed out. “Energy gets absorbed, so the challenge will be for antennas to become more focused.” 11ad is likely to support a personal basic service set mode. “This can be seen as a personal area network,” Edgar explained. “Because 11ad will essentially be short range, this will be good for personal communications as there’s no interference.” 802.11ad may also enhance Wi-Fi Direct, the technique that allows Wi-Fi devices to talk to each other without the need for hot spots. Using OFDM, the draft standard is expected to support 6.8Gbit/s. “But you’ll need 32 antennas to get the highest speeds,” Edgar warned, “so beam forming is a ‘must’.” However, gain increases with antenna area, which supports higher powered links. Consumer electronics is a potential user. “I’m sceptical about 60Hz being good for video transmission,” Edgar continued. “Previous attempts have been made at this frequency and I’m not sure how Wi-Fi will be different. While it could be good for linking a laptop to a monitor, it won’t be a whole house application.” Other applications could include high speed file download and networking. “If it works, you will download movies in seconds,” he said. It’s likely an 11ad radio will have to be a system in package, with the antennas on top of the chip.

22 November 2011 19

Cover Story Wi-Fi

22 November 2011

100 104 108 112 116 120 124 128 132 136 140 100 104 108 112 116 120 124 128 132 136 140

149 153 157 161 165

36 40 44 48 52 56 60 64 36 40 44 48 52 56 60 64

standard. “The IEEE does these Fig 2: 80MHz and 160MHz channels in the 5GHz spectrum ‘wrap ups’ from time to time,” US configuration Edgar explained. “The current 5170 5330 5490 5710 5735 5835 baseline is IEEE802.11-2007 and MHz MHz MHz MHz MHz MHz • 24 channels at 20MHz the new one will be 802.11-2012, (802.11a/n) with all current ratified standards IEEE channel • 11 channels at 40MHz included.” Reading this document (802.11n) 20MHz will not be a task for the • 5 channels at 80MHz 40MHz (802.11ac) fainthearted: the publication is 80MHz • 2 channels at 160MHz likely to run to 2500pages, or a 160MHz (802.11ac) 16Mbyte PDF. Europe, Japan and rest of the world It’s where Wi-Fi goes from that 5170 5330 5490 5710 point that holds interest; not only MHz MHz MHz MHz in the new variants that are being • 19 channels at 20MHz (802.11a/n) considered, but also in the IEEE channel • 9 channels at 40MHz competition that may appear from (802.11n) 20MHz other areas, such as WAPI; the • 4 channels at 80MHz 40MHz WLAN Authentication and Privacy (802.11ac) 80MHz Infrastructure developed in China. • 2 channels at 160MHz 160MHz (802.11ac) One of the top line trends is the move away from 2.4GHz in favour of 5GHz and then 60GHz. “There’s too much interference at 2.4GHz and, quite simply, there’s not enough IEEE802.11af spectrum,” Edgar noted. But the technology is also looking to move into Targeting those parts of the spectrum vacated by analogue tv lower frequencies, including the whitespace part of the spectrum – broadly transmission, 802.11af will offer longer range communications. The 600 to 800MHz. concept is reliant upon a central database to allocate channels. “An Databasing will be central to the use of whitespace (see 802.11af box), access point (AP) has to negotiate with that database,” Edgar explained. but this approach might be extended to the 2.4GHz band. “If that proves “The AP sends its coordinates – including Z, because that’s important – and the database sends a list of available channels. The AP then assigns successful,” Edgar pondered, “it might then get applied at 5GHz.” a channel to a device.” Four new PHYs In the UK, Ofcom has added a time element, restricting access to certain These moves are encompassed in the development of four new physical channels at particular times to protect wireless microphones used at layers, or PHYs. “11ac will run at 5GHz and is scheduled for ratification in concerts. 2013,” Edgar said. “11ad, coming in 2012, will run at 60GHz and is being “802.11af may also be used to offload mobile phone traffic,” Edgar developed by the Wireless Gigabit (WiGig) Alliance. 11af, planned for 2013, will suggested. “Whitespace is being looked at as a way to do this because of use whitespace, while 11ah, likely to appear in November 2014, will operate at the range it offers. Along with support smart grid applications and frequencies of less than 1GHz and find application in smart grid and M2M.” sensors, 11af may also enable rural broadband and it could have application in interactive tour guides.” In Edgar’s view: “There’s a sea change in Wi-Fi; it’s exploding into new markets. People want things to work faster and if there’s spectrum available, Wi-Fi should have it.” The mantra appears to be ‘one MAC, many IEEE802.11ah PHYs’. Operating at frequencies of 1GHz or less, 802.11ah will have a As part of this ‘explosion’, Wi-Fi is moving away from its traditional home transmission range of up to 1km and could support up to 6000 in the pc and networking industry. “It’s becoming an all encompassing associated stations. “There’s a lot of license exempt spectrum available,” technology,” Edgar ventured, “and is starting to take share in markets that Edgar asserted, “and this may be an area which suits software defined radio.” were seen as complementary – even Bluetooth.” The consequence is that design will become harder. “At 60GHz, cmos The draft standard is likely to prove attractive to companies developing design is quite tricky and one of the challenges for silicon companies is that technology aimed at smart grid applications. “The problem is there are they’re getting to the point where shrinking the rf part isn’t economic any more than 100 potential markets,” Edgar said, “and each isn’t very large. longer. It’s unlikely we’ll see the rf element shrink beyond 45nm, but we’ll But, together they’re big. Developing silicon to serve these markets will not be easy, neither will software development.” still want the digits to shrink,” he said. It’s therefore likely that Wi-Fi chips will become SoCs. “But if these are Although capable of supporting data rates of up to 600Mbit/s, 802.11ah done properly, with the peripherals integrated, then this will simplify applications may actually be handling something around 100kbit/s. product design,” he concluded.

www.newelectronics.co.uk

Uptime in a box. Put an end to unexpected repair costs, timeconsuming paperwork and expensive spare equipment. Beneﬁt from expedited service and prolong your warranty with a cost-effective service pack. That’s advantageous. That’s Agilent. Agilent Advantage Service Pack Priority Speed Fastest turnaround time in the industry Full Calibration Equipment returned calibrated after repair Extended Protection Add 2 yrs. to existing Agilent warranty Purchase Options Available at time of product purchase or during warranty period

www.newelectronics.co.uk

Get your Agilent Advantage www.agilent.com/ﬁnd/advantagepack UK 0118-927 6201 Ireland 1890-924 204

22 November 2011 21

Bouncing back After years of offshoring, the UK’s contract electronics manufacturers are seeing strong order books. By Graham Pitcher.

he impression given by a range of national media is that UK manufacturing, in general, is on the ropes. But when it comes to the electronics sector, nothing could be farther from the truth; certainly in the opinion of Phil Inness, chairman of the Electronic Manufacturing Services Association (EMSA) group within trade association Intellect and managing director of Bedford based manufacturer Axis Electronics. He believes the UK contract electronics market is probably worth £1.4billion a year. “The market is in pretty good shape,” he observed, “and is certainly growing in excess of 5% a year.” In his role as EMSA chair, he sits down on a quarterly basis with the members to see how things are going. “Most companies are positive,” he reported, “and have been for the last year. As far as we can tell, order books are as strong as they have ever been.” The one potential dark cloud on the horizon is a decline in business. “Some comments were made at our last meeting about a ‘softening’ in demand, but those companies have been unable to quantify their feeling.” The performance of the UK’s contract manufacturing sector is encouraging, given the degree of offshoring which has taken place over the last decade. “There has been a mass migration of work offshore in the last 10 years,” Inness noted. “Some of this should have gone overseas without question,” he accepted, “while some should not have, but did. Companies now realise that offshoring isn’t going to be a fix for all evils and there is much cleverer decision

22 November 2011

making today.” The challenge of offshoring has seen the UK EMS sector improving its efficiency in the last five years, Inness believes. “There are now a lot of good UK companies that can do a good job at a good price,” he asserted. “When you compare that to the risks involved in offshoring, it makes sense to keep the work here in the UK.” Inness reflected that many companies jumped on the offshoring bandwagon without giving the move enough thought. “They may have realised certain savings, but then ended up with obsolete stock or found the work was wrong and had to be put right, with all the time delays involved. Now, there’s smarter procurement; if someone wants 73 units, they can order 73 units from a UK company and have no wastage. If you go offshore, you may have to order 100 units or more to get the price breaks.” He sees three distinct bands of EMS business. “At one extreme, there’s high volume consumer. At the other, low volume, high reliability. And in the middle is a large amount of business up for grabs.” Vying for this business are some 250 companies, broadly grouped into four bands. “There are the multinational names,” Inness said, “then 10 companies or so turning over roughly £50million a year. Below them is a group of probably 50 or 60 companies doing between £5m and £20m a year, then the rest.” In general, said Inness, the UK’s EMS sector is recruiting and investing. “Companies continue to invest in new production equipment. As technology

Top: EMS companies need to provide products to specification, on time and at a competitive price Above: Axis has a Class 10,000 cleanroom, supporting bare die attach, wire bonding and integration for rf products

changes, they have to keep up and the industry, as a whole, is much closer to the leading edge than it has been and more capable of responding to customers’ needs.” With the technology in place, Inness believes that EMS companies don’t necessarily have to sell. “It’s all about giving the customer what they need so they can sell their products on the global

www.newelectronics.co.uk

Sector Focus Contract Manufacturing

market. They want top quality products made as quickly as possible at a competitive price.” With new markets opening up, Inness believes it’s a good time for the UK EMS sector. “Renewable energy is bringing opportunities, as is wireless technology. I’m also hearing good stories about medical, but I have yet to see anything of substance.” Underpinning everything,

from those companies.” He also noted that, during the last six months, EMSA has been working more closely with Intellect’s PCB Manufacturing Group. As far as Axis Electronics is concerned, business is good. “We grew revenues by 50% in our last financial year and are 20% ahead of the same time last year,” Inness said. “There’s a strong order book across all sectors and what’s driving this is customers we got involved with a couple of years ago placing business.” Headcount is also growing. “We are now around 160 people,” he continued, “which is almost double that of 18 months ago.” Yet Inness admits that getting the top quality people needed to run the business remains a challenge.

Inness: “There are now a lot of good UK companies that can do a good job at a good price.”

however, is the traditional strength of the aerospace and defence sector. He described business here as revolving around ‘a basket of products, some of which have been around for ages’. “But there is leading edge business emerging and a lot of embedded computing.” Even so, he believes companies still need to be ‘clever’. “There’s a range of requirements which need to be met in order to get business from new customers.” One item on the agenda at the next meeting of EMSA may well be trying to improve the sector’s visibility within Intellect. Although one of Intellect’s groups, EMSA is not always immediately obvious to Intellect members. “Intellect has a large membership,” Inness pointed out, “and we want to get more benefit

www.newelectronics.co.uk

Investing in the latest technology is critical for EMS success

Here, he suggests the Government could do more to help by providing tax credits against training costs. “People are losing their jobs in the public sector and we’re struggling to get skilled employees. Let’s get some support to help us retrain them.” Business is also growing through making better use of existing equipment, including additional manufacturing shifts. “But we’re also boosting our security classification and the additional services we offer – such as microelectronics design, conformal coating, environmental screening and product repair – are making meaningful contributions.” Axis is also ‘pushing hard’ on the SC21 defence supply chain initiative. But, like small businesses around the country, Axis faces the challenge of making changes and growing at the same time. “Trying to overlay business improvement is challenging,” Inness admitted. Inness’ recipe for contract manufacturing success is to invest in technology and people and to have the right processes. “You have to look after all three,” he contended. He acknowledges this involves climbing a learning curve. “Successful companies are following the principles,” he noted, “while some aren’t, but will get there.” His worry is that some companies will not. “They will go ‘pop’,” he believes, “but there won’t be too many of them.” Neither has Axis had problems in getting access to the money it needs to expand. “Few members of EMSA have complained about the lack of access to funds. Banks have the money,” Inness believed, “and it’s a great time for EMS companies to invest.” Now, having broadly put its house in order, it seems UK companies are beginning to win high volume manufacturing contracts that, only recently, would have been placed in the Far East without second thought. How times change. www.axis-electronics.com www.intellectuk.com

22 November 2011 23

Technology Watch Introduction

Making the link

lugging things into computers used to be something of a lottery; the chances were that things simply wouldn’t work; maybe an obscure setting had not made correctly. And even if the peripheral could be ‘seen’ by the host PC, that didn’t always mean it would work in the way you expected. Over the years, the computer industry has been good at overcoming issues like this and the solution that has dominated the market since the late 1990s is the Universal Serial Bus, or USB. With a bit of help from the operating system, USB brought plug and play to the PC and to a wide range of peripherals. Where, in the old days, one peripheral occupied one port, USB enabled daisychaining – in theory, you could attach 127 devices to one port – and the emergence of the USB stick, the portable memory device without which, it seems, we cannot survive. USB wasn’t, however, the ‘slam dunk’ that it appears. Competition came from Firewire, which could support up to 400Mbit/s at a time when USB only offered up to 12Mbit/s. USB won through when version 2.0 was launched, despite the fact that Apple was a major Firewire supporter. In the end, Apple climbed on the USB bandwagon in 2003. Now, the unrelenting thirst for bandwidth is pushing the development of USB version 3.0, but the gestation period has been long; work started in the mid 2000s and it is only now that USB 3.0 enabled devices are appearing. But the wait should be worthwhile; USB3.0 brings data transfer rates of up to 5Gbit/s. Even so, there’s always an opportunity for Apple to ‘go its own way’ and it has recently – in association with Intel – brought out Thunderbolt, said to be capable of handling 20Gbit/s, with a 100Gbit/s version on the drawing board. Whether Thunderbolt will make a dent on USB’s dominance of the PC world remains to be seen, but Apple’s interest in any market holds the potential of moulds being broken.

Have you thought how difficult life would be without USB connection? This common interface specification allows plug and play connectivity at data rates approaching 240Mbit/s. While the industry is readying itself for USB3.0 and even faster data rates, another contender has appeared. Digi-Key is pleased to partner with New Electronics to look at the future for serial communications.

Graham Pitcher, Editor, New Electronics

Mark Larson, President, Digi-Key

As an extension of its commitment to providing top quality product, Digi-Key is pleased to partner with New Electronics to provide relevant, useful information to UK engineers.

www.newelectronics.co.uk

22 November 2011 25

Long-running serial

hen you consider how difficult it was to hook up peripherals to a PC in the late 1980s and early 1990s, it is little wonder that the Universal Serial Bus (USB) should have been such a success. Users had to wrestle with arcane interrupt and address selections to attach more than a couple of serial or parallel peripherals to a computer, often with unpredictable results and rarely entirely successfully. Realising that, with the move to Windows, things wouldn’t get better if PCs were stuck with RS232 serial and IEEE1284 parallel ports, seven companies clubbed together to try to improve I/O. When the first USB silicon appeared a year later, it promised a much easier life for PC users, although it took several more years for the interface to be adopted widely. One problem was that, although USB was supposed to support more than 100 peripherals connected to a single host port through a tree of intermediates, in practice, this did not turn out so well. It took an update to version 1.1 for the specification to be robust enough to handle hubs. It was only after version 1.1 appeared that USB ports came into widespread use, roughly coinciding with the release of Windows 98. In USBv1, peripherals could support either Low Speed, with a 1.5Mbit/s transfer rate, or a 12Mbit/s rate with the highly confusing name: Full Speed. Consumers naturally assumed that Full Speed-capable USB 2.0 hubs and devices would support the later revision’s higher maximum data rate when, in fact, they would only run at up to 12Mbit/s. Over time, USB has competed more strongly with the IEEE1394 Firewire interface championed by Apple, which

22 November 2011

USB3_RX USB3_TX

GND

D–

D+

VBUS

GND

USB 3.0 cables have nine wires instead of the previous four. The cables also feature modified connectors.

spent close to a decade in development before appearing as standard on Macs. Apple wound up adopting USB – putting ports on its machines before the 1.1 revision was complete – ahead of its favoured I/O standard. At the time, the two interfaces occupied different parts of the market. Firewire was designed to daisychain a comparatively low number of peripherals, instead of attaching them through hubs. The big difference was the peak datarate. The low-voltage differential swing (LVDS) interface represented, at the time, a marked change in the way that I/O worked electrically. The reduction in voltage swing, to just 350mW in each wire, reduced electromagnetic interface dramatically and allowed comparatively high datarates. At introduction, Firewire could pass up to 400Mbit/s, allowing it to be used as a replacement for the SCSI bus – Apple’s original intended application for the I/O standard. Another key difference from USB is the amount of host intervention needed – something that helped Firewire maintain a small, but significant, grip on audio and video peripherals even after

the introduction of USB 2.0. Partly because it was intended to be used for hard drives, Firewire has a comparatively complex command set and has built-in support for direct memory access (DMA) transfers. USB, by contrast, generally used programmed I/O to send and retrieve words from the interface, although the adoption of the Open Host Controller Interface (OHCI) did allow the controller to offload some transfer functions from the host processor. The second major version of USB appeared in 2000 – offering a top claimed datarate of 480Mbit/s. To distinguish High-Speed peripherals from the existing Low-Speed and slightly ironically named Full-Speed devices, the USB Implementer’s Forum developed a ‘chirping’ protocol that the newer devices could recognise but which would not confuse older interface controllers. Once set, the host would treat the device as a High-Speed slave until the next reset. USB 2.0 was made a firm standard in 2001, quickly turning into a mainstream offering on PCs and peripherals. Even Apple, which held out against offering USB 2.0 ports on its machines – largely

www.newelectronics.co.uk

Technology Watch USB

Chris Edwards explores the world of serial communications between PCs and peripherals

Fig 1: How mixed USB systems communicate CPU

DRAM

Host controller

USB host controller

FS hub

SuperSpeed Links

HS hub

High-Speed Links Full-Speed Links LS

Low-Speed Links

because it already had high-speed peripheral support through FireWire – started to support it from 2003. The dramatic success of USB 2.0 is, in some ways, a problem for its successors. There is not such a huge pent-up demand for a new interface as there was for USB 2.0. However, there are applications such as high-end audio and video storage and capture systems that can make use of additional bandwidth, not least because real-world datarates on USB 2.0 tend to top out at around 240Mbit/s. USB 3.0 has taken a while to get to where it is now. Development work

www.newelectronics.co.uk

In USB 3.0, hubs will route packets directly to the target device so that other devices in the tree are not forced to wake from sleep

started in the mid-2000s, with an initial specification appearing in 2008. Even now, it is only just beginning to appear on PCs and high-speed peripherals. The interface is not expected to make it into Intel’s motherboard chipsets until Panther Point arrives in 2012. USB 3.0 does make extensive changes to the protocol, but maintains separate signal lines for USB 2.0 and 1.1 compatible devices. It even needs a slightly silly name to distinguish its protocol from the High Speed and Full Speed modes of its predecessors: SuperSpeed.

To improve bandwidth, USB 3.0 adopts much of the physical layer from PCIExpress 2.0, such as the 8B/10B encoding system and data scrambling to reduce electromagnetic interference. The scrambling technique prevents repetitive bit patterns, such as 10101010, from generating strong frequency peaks. A further change is that connections are no longer half-duplex: there are separate data lines for transmit and receive, which should make better use of the maximum available data rate of 5Gbit/s than USB 2.0 can make of its nominal 480Mbit/s. More advanced forms of LVDS signalling have made it possible to transmit at several gigabits per second over a differential pair through the use of pre-emphasis and active equalisation. But the SuperSpeed protocol is very sensitive to cable length such that the distance from the USB controller in a host chipset to the connector at the edge of the PCB is now a major source of performance loss. For this reason, some of the electrical conditioning is moving out of the chipset and closer to the cable. Manufacturers are now selling redrivers that provide a boost for weakened signal just before it crosses from the connector to the cable. A further change is that packets are no longer broadcast across a tree of devices (see fig 1). Hubs will route packets directly to the target device so that other devices in the tree are not forced to wake from sleep to check on a packet any time something appears on the bus, as with USB 2.0. The data-transfer protocol is more streamlined for SuperSpeed, partly thanks to the adoption of the full simplex model (see fig 2). In previous forms of USB, data transfer involved a multistage

22 November 2011 27

The SuperSpeed protocol is very sensitive to cable length such that the distance from the USB controller in a host chipset to the connector at the edge of the PCB is now a major source of performance loss

handshake. First, the host would send an IN-token packet to initiate the transfer. Once the slave had responded, the host would send an ACK packet and, in the case of high-speed transfers, would probably immediately follow that with another IN-token. In SuperSpeed, ACK packets have multiple functions. Instead of sending an IN-token, a SuperSpeed host will kick off a transfer using one form of ACK. Once it has received the payload, it will send another ACK that contains a command for the next chunk of data and keep doing so until it sends a final ACK that does not request additional data. There is a similar change for outgoing packets that helps to reduce protocol overhead on the bus. Higher-speed peripherals can take advantage of data bursting in which the host asks for a number of data packets to be sent in sequence. The host can request as many as 16, sending a subsequent ACK only when all of those packets have been received. One of the key changes in USB 3.0 is to reduce the number of times a host polls peripherals to see if they have data to send or are still operating on the bus and have not been disconnected (fig 2). Because of the master-slave organisation of USB, a peripheral can only send data when polled by the host with an IN-token. As the host has no idea when data might arrive, it simply polls on a regular basis at a frequency set by the operating system. Windows usually defaults to 125Hz for mice. If the mouse receives an IN-token and it has not detected any movement since the last one, it will send a NAK packet, telling the host nothing has happened. The host will simply wait for another 8ms before sending another IN-token to see if

22 November 2011

anything has changed in the meantime. The SuperSpeed mechanism handles the situation somewhat better. For example, if the peripheral is a disk drive responding to a read

command from the operating system, it will have to wait for the head to reach the correct tracks and for data to start streaming back. If the host sends an ACK request immediately after issuing the read command, the data will not be ready. Under SuperSpeed, the drive will send a NRDY packet saying, in effect, it has nothing to send yet. However, instead of being forced to wait until the next time the host asks for data, the peripheral can, without prompting, send an ERDY packet. The host will then respond immediately by transmitting a new ACK request and the peripheral will start sending the data. Because it reduces the amount of polling needed, the new mechanism improves link-power management dramatically for peripherals with bursty, intermittent behaviour. Although USB 3.0 increases the amount of power that a hub can deliver to a peripheral – 900mA, instead of 500mA – it also has features to prevent power consumption from spiralling out of control and to deal better with peripherals that need to sleep to save power. To maintain synchronisation, SuperSpeed devices have to transmit

The USB 3.0 type A connector, left, and the type B connector, right. Type B parts feature modified USB 2.0 type B connectors, with SuperSpeed pins added on top. All USB 3.0 connectors are coloured blue to aid identification

packets constantly. This is because the equalisation system uses electrical training sequences to ensure the receiver can detect bit transitions properly and these are maintained through idle sequences once a link is established. Unfortunately, this translates into a big source of energy consumption. To overcome this, if a peripheral does not need to send data for a while, it can tell the host it is moving into a low-power mode and will retrain the link when it becomes active again. There are three power-down modes in USB 3.0. U1 is a fast-recovery state, where the node can reduce the frequency of keep-alive transmissions but return to normal transmission within microseconds. U2 offers a bigger power saving, but a slower recovery – this time measured in milliseconds. U3 is suspend mode, which extends recovery time further, but is still of the order of milliseconds. It can only be entered into under software control, whereas U1 and U2 can be implemented using hardware timers. The transition to USB 3.0 has provided

www.newelectronics.co.uk

Technology Watch USB

Earlier in 2011, Apple launched MacBook Pro computers sporting an interface called Thunderbolt. Developed primarily by Intel, the plan for Thunderbolt had been to use optical signalling to increase bandwidth to, ultimately, 100Gbit/s

Fig 2: Comparing back to back IN transactions Host controller

Host controller

ACK

5 DATA

IN token 3

IN token

2 1

High speed

another opportunity for Apple to go its own way. Earlier in 2011, the company launched a series of MacBook Pro computers sporting an interface called Thunderbolt. Developed primarily by Intel under the name Light Peak, the original plan for Thunderbolt had been to use optical signalling to increase bandwidth to, ultimately, 100Gbit/s. But the light went out on Light Peak when Intel claimed it could hit the initial target datarate of 10Gbit/s using more advanced signalling over differential copper pairs. The cabling requirements for Thunderbolt, although not yet publicly disclosed, are even more stringent than for SuperSpeed USB as a consequence of the higher datarate. Signal conditioning now goes inside the cable itself – just behind each connector – so it can be calibrated for the correct electrical performance at the factory. Manufacturers such as Gennum are

www.newelectronics.co.uk

DATA Hdr+ payload

ACK header

ACK DATA

ACK header

Super speed

offering signal conditioners that will fit onto a tiny PCB that can be attached to the connector. Like FireWire – and in contrast to USB – Thunderbolt is a peer-to-peer technology. There is no master at the top of the tree that is needed to initiate transfers. This decision for USB demanded a key change to the protocol to allow peripherals, such as cameras or phones, to sometimes act as masters so that they could transfer pictures to an external storage device without calling for intervention from a host PC. The OnThe-Go (OTG) variant of the USB standard allows peripherals to turn into masters when necessary. The situation for role reversal on USB 2.0 is slightly more complex than it at first seems, due to the way the roles are reversed at the electrical signalling level and not just through an additional logical protocol.

One of the key changes in USB 3.0 is to reduce the number of times a host polls peripherals

The peer-to-peer nature of FireWire enables, for example, the target disk mode supported by Macintosh computers. Using Firewire, one computer can access another’s disk drives over the bus, with the remote machine effectively taking control of the other without direct intervention from the target machine’s OS. However, the DMA support and peerto-peer nature of FireWire and Thunderbolt threaten to open a security hole in computers. Using DMA, it is possible for a remote machine to access any physical area of memory in the target machine that is reachable by its FireWire DMA controller. A proof of concept attack was demonstrated in 2006. In principle, a hacker could walk up to unprotected machine, attach a FireWire peripheral and minutes later walk away with sensitive data found on the target computer. The target machine might expect DMA transfers from FireWire to be made to known I/O buffers. But, as normally implemented, the DMA controller does not limit access to only those areas. They could be parts of the machine dedicated to kernel operations. In practice, OSs such as OS X lock access to FireWire DMA if a password has been set and protection activated by the screensaver. It is currently unclear whether protective steps have been taken for Thunderbolt or how vulnerable it is to attack. A bigger concern for Apple and Intel is whether the additional promised bandwidth will convince peripheral makers to support Thunderbolt or stick with USB 3.0 which, despite its slow start, is likely to dominate the PC industry within the next five years.

22 November 2011 29

Power to the people

he fuel cell is one of those technologies that never quite makes it to the mainstream. Yet it is almost as old as the battery that many want it to replace. Sir William Grove, who devised the first one in 1839, called it a ‘gas voltaic battery’. Knowing that it was possible to split water molecules into oxygen and hydrogen by passing an electric current through the liquid, he found it was possible to reverse the process: combine oxygen and hydrogen to produce water and electricity. It took 50 years for the term ‘fuel cell’ to appear, when Ludwig Mond and Charles Langer worked on developing a commercially viable version. NASA has used fuel cells for decades. But the alkaline fuel cells employed in the space programme had one clear design objective: to provide high energy density. The water they produced was also handy side benefit: it could be drunk by the astronauts. Operating cost, however, was not an primary concern. Devised by British engineer Francis Thomas Bacon and subsequently named after him, the alkaline fuel cell (see fig 1) uses a solution of potassium hydroxide in water and stored in a porous solid matrix. Oxygen and hydrogen are pumped in as a charge is applied. Hydrogen introduced at the anode decomposes into protons and electrons. The electrons pass through an electrical connection to the load; the positive ions combine with negatively charged hydroxyl ions that pass through the electrolyte solution to produce water that is then pumped out of the system. Unfortunately, CO2 and even water itself poison the process, so the cell has to be sealed from the atmosphere. Because the unit has to be sealed, NASA

22 November 2011

A BASF researcher working on catalytic exchange membrane materials for proton exchange fuel cells

could get away with using asbestos as the matrix for the electrolyte chemical. The catalysts needed for the cell can also be pretty cheap, using metals such as nickel. The Apollo programme employed platinum for its higher efficiency. Overall, the cell is very efficient: only around 30% of the energy it generates is lost. But the cost of sealing and maintaining the purity of the chemicals needed makes the alkaline design an

unlikely candidate for the fuel cell of the future. One way around the problem of alkaline fuel cells is to change the electrolyte. The approach that the US Department of Energy reckons will work best for future vehicles is the polymerbased proton-exchange membrane. Instead of using a porous ceramic soaked in electrolyte, this uses a thin plastic membrane not unlike clingfilm in overall look and feel, although it is normally a fluoropolymer like Teflon rather than polyethylene. The idea is to allow protons to pass through the membrane, but to block electrons so electron transfer occurs only by completing an electrical circuit from anode to cathode. Fluoropolymers are good electrical insulators, but can be turned into ionic conductors. For example, DuPont’s Nafion puts sulphonic acid groups onto a Teflon polymer backbone. Protons on the acidic nodes can hop from one to the

Fig 1: An alkaline fuel cell Electron flow Load

Hydrogen

Oxygen

Hydroxyl ions Water

Anode

Electrolyte

Cathode

www.newelectronics.co.uk

Technology Watch Fuel Cells

Despite holding great promise, Chris Edwards finds the fuel cell has yet to breakthrough.

Fig 2: The proton exchange membrane fuel cell Load +

– 6e–

–

6e CO2 + 6H

CO2 Water, unused methanol/water

H2O + CH3OH

Fuel methanol/ water

Anode (–electrode)

other and, in an electric field, will tend to move one way through the membrane towards the cathode. The fuel cell can work at relatively low temperatures compared with other designs: 100°C is normal for a protonexchange membrane design. Because the electrolyte can be reduced to a thin membrane, the cell is relatively compact and easy to scale up for large power densities. It also starts up quite quickly and is not poisoned by gases such as carbon monoxide. These factors make the proton-exchange membrane cell (see fig 2) the most likely option for hydrogen powered vehicles, even though the 50% operating efficiency for today’s designs is much lower than the Bacon cell’s. The big problem with the protonexchange cell is its reliance on hydrogen. As a component of water, hydrogen is hardly scarce, but it takes a lot of energy to obtain molecular hydrogen and then transport and store it. Research is under

www.newelectronics.co.uk

H+

Proton exchange membrane

The proton-exchange membrane cell is the most likely option for hydrogen powered vehicles

3H2O

Water, unused air

6H+ + 3/2 02

Oxidant air (oxygen)

Cathode (+electrode)

way to find more economic ways to liberate hydrogen from water. One possibility is biotechnology. Schemes such as the EU-funded BioModularH2 project have been formed to develop organisms that feed on sunlight to power the production of hydrogen from water or feedstock chemicals such as acetates. Bacteria that crack water in hydrogen and oxygen exist – many are nitrogen-fixing species already useful in agriculture that produce hydrogen as a part of the process. However, they produce relatively little gas compared with the amount of energy and food they consume, so scientists are trying to redesign the enzymes they use to make them more efficient: the best naturally occurring hydrogen producing enzymes are, unfortunately, poisoned by oxygen. Some researchers are trying to tweak the enzymes to make them less sensitive to oxygen; so far with limited

success. Another approach is to stick with the natural enzyme and increase production by engineering proteins that are efficient at removing oxygen before it can do any harm. These hydrogen producers are longer-term options: noone is looking at a time-scale shorter than ten years before even pilot production. Even if hydrogen becomes easy to produce, it remains a poor choice for portable applications which are saddled with slow-to-evolve battery technology. However, mildly acidic organic liquids, such as ethanol and methanol, make good substitutes for molecular hydrogen as they will donate protons for these reactions. The direct ethanol fuel cell can even use the same type of protonexchange membrane as the hydrogen version. One big advantage of using ethanol is that a biomass industry has been established. The ethanol group remains on the anode side to be oxidised into carbon dioxide, donating protons that can cross over to the cathode as part of the process. The most promising candidate for portable devices remains the direct methanol fuel cell. Here, methanol is dissolved in water, with the recombination of ions taking place at the cathode. However, this is the cell’s main drawback – because methanol has to cross from anode to cathode, the reaction is much slower and even less efficient than the proton-exchange cells. Today’s designs also tend to produce less than 0.5V. Fuel cells suffer from polarisation which means that as current density increases the voltage tends to drop. Close to peak current, the voltage can drop off dramatically because of losses from the

22 November 2011 31

Technology Watch Fuel Cells

The most promising candidate for portable devices remains the direct methanol fuel cell, in which methanol is dissolved in water, with the recombination of ions taking place at the cathode

Fig 3: A generic fuel cell

Load 2e– Oxidant in

Fuel in 0.5O2

H2 Positive ions

Negative ions

H2O

Electrolyte membrane

Depleted oxidant and product gases out Anode

effects of transporting a high concentration of fuel across the electrolyte – it starts to take a long while to refresh the chemical at the interface and remove the waste products. As a result, cells need to be stacked to develop a usable voltage. In portable systems, this is likely to be achieved through a large number of cells constructed using microfluidic techniques to prevent the size of the cell from spiralling out of control. Although methanol is both toxic and flammable, the International Civil Aviation Organisation’s dangerous goods panel voted in late 2005 to let passengers carry micro fuel cells and fuel cartridges onto airplanes. The US Department of Transportation decided in 2008 to allow up methanol cartridges, of an approved design, to carry up to 200ml in liquid – twice that of the current volume allowed for cosmetics in carry-on baggage. However, the problem for methanol fuel cells remains less one of fear of an airline ban, more their real-world performance.

22 November 2011

H2O Depleted oxidant and product gases out Cathode

Fuel-cell construction is trickier than with proton-exchange designs because it needs to use water to dilute the methanol and encourage the protons and the methanoate groups to disassociate. As water adds to the weight, it makes more sense to recycle the liquid, rather than to supply it fresh. That adds complexity to the design. Also carbon dioxide needs to be removed efficiently from the solution that passes out of the fuel cell. Although the aim is ultimately to power laptops and phones, the main target for methanol fuel cells currently lies in military applications: replacing bulky batteries for backpack radios and other battlefield electronics. If the fuel cell does not need to go anywhere, the options expand considerably. Stationary, grid-based cells might provide short-term generating capacity to cope with peaks in demand or for reversible systems as alternatives for batteries in power networks that have a large proportion of generation based on

Military applications remain the most immediate target for methanol based fuel cells, replacing bulky batteries for battlefield electronics

renewables. As they can be fixed in place and shielded, they can use more extreme fuels and processes. For example, the protonic ceramic fuel cell needs to operate at more than 700°C in order to oxidise gas-phase molecules electrochemically. These ions can pass through a porous, solid electrolyte without demanding the use of a liquid that might leak out over time and contaminate the ground. However, this design has a low current density, although this can be increased with a thicker electrolyte layer. As it can support an efficiency of up to 65% using pipeline-borne natural gas, this is one looks to be a good candidate for gridbased cells. Another technology suited to use in stationary cells is the phosphoric-acid fuel cell. While this operates at 200°C and uses the corrosive acid as an electrode, pilot plants have been built and are being tested at a number of sites. Although large cells such as these work at high temperatures, some researchers have pursued the option of using the solid-oxide design in portable products. The Fraunhofer Institute has developed one that uses methane as its fuel source, although it is aimed primarily at military systems that need 100W. However, the Massachusetts Institute of Technology has developed one using that uses infrared light, generated by incandescent gas as an intermediate form of energy, although efficiency was just 5%. Even though parts of the industry seem to have settled on mainstream architectures, such as proton-exchange or direct methanol, more than 170 years since its invention, the options for the fuel cell are still pretty open.

www.newelectronics.co.uk

For more information on the following jobs enter the reference No. on... www.totallyengineering.com/ne

Electronics Engineer Essex

Type: Contract Salary/Rate: Negotiable An automotive client, based in Essex, is looking for a Junior Electronics Engineer. This will be for an initial project until the end of the year, followed by a 12-month extension. The candidate will need experience of electronics design and development. She/he will need to have at least 2 years’ industrial experience in circuit and general electronics design. • Knowledge of automotive electronic products • Analogue circuit design experience • Design and development experience of circuit design • Experience of schematic capture & circuit simulation • Degree/HND in Electronics Engineering or related area.

For full details online enter reference: JS38722

Electronic Hardware Design Engineers Location: South East Type: Contract Salary/Rate: Good, hourly 2 x Electronic Hardware Design Engineers required on a CONTRACT basis by leading engineering blue chip to work on high profile electronic design programme. Role: Specification and design of electrical and electronic hardware, harnesses, assemblies and their associated components Investigate & solve design faults that affect the Electronics Department. Key Requirements: Experienced analogue electronics design engineer. Beneficial: Experience of working to Mil Standards Loom design experience. Start: ASAP Duration: 3-4 Months + (extension likely)

For full details online enter reference: JSHW

Embedded Systems Electronic Engineer

Component Engineer

Location: Cambridge, Cambs Type: Permanent Salary £35k-£45k per annum plus excellent benefits

Location: Crawley, West Sussex Type: Permanent Salary/Rate: To be advised

Job Details: This company is looking for an experienced Electronic Engineer to join their Embedded systems group. The group solve complex problems, using the very best electronics, software and systems engineering skills on a wide range of projects, involving a combination of: • Analogue design (discrete level, and device level designs), high level digital (Micro controller, DSP, FPGA etc), Power Electronics, and ultra-low power design techniques • Signal/image Processing, feedback control including robotics, algorithm development and implementation • Safety Critical, including medical, software design. The key areas of this role include the development of electronic and electrical aspects of complex electromechanical products. Direct customer-facing responsibilities to understand and document the software requirements, and following quality procedures and processes, such as ISO 9001:2008 and ISO 13485:2003.

For full details online enter reference: JS-.OPT_EMBEELECENG

Working within the Radio Communication Product business segment, within Defence Security/Air Operations domain for Thales UK. Primary Purpose of the Role: To technically support the RCP project portfolio, including new design work and maintenance of existing products and systems. Principal Relationships: Line management by Hardware Manager (Crawley). Routine tasking by project manager(s), routine oversight by technical lead(s). Work closely with other technical and nontechnical staff on project teams. Key Tasks: Electronic design: digital and analogue; Technical assistance to production; Preparation of design documents; Presentation at design reviews; Test and measurement. Technical & Professional skills: Ability to understand engineering design; Capable of reading and understanding data sheets; Able to understand and interpret component requirements; Digital design; Analogue design; Test and measurement; Report writing.

For full details online enter reference: JS1103218

Electronics Design Engineers

Electronics Engineer (DIGITAL)

Location: Durham Type: Permanent Salary/Rate: 25k-£45k per annum + benefits Job Details: Switch Mode Power Supply Design, SMPS, PSU Designs, AC/DC SMPS, SMPS DC/DC, Switching Power, Low Power RF, RF Sensing, LED drivers, Mosfets, Analogue/Digital Electronic Circuit Design, Hardware Design Engineer, MatLAB, Simulink, MathCAD, EMC.

Job Details: Thales UK (DAV & DMS) provides complete system solutions for all types of fixed or rotary wing aircraft in the civil and military sectors. As a system integrator, prime contractor and supplier of value added services, it delivers cutting-edge solutions to meet the operational requirements in the fields of combat, surveillance and air transport, in addition to regional and business aviation.

This well established organisation is looking for experienced Electronics Design Engineers to work on the design of high efficiency, digitally controlled Electronic Applications devices and hardware topologies for emergency control gear. You will analyse new circuit concepts using tools, such as MatLAB, Simulink & MathCAD. You will accompany a product through its complete lifecycle: concept, simulation, realisation, through to production.

Location: Crawley, West Sussex Type: Permanent Salary/Rate: To be advised

This post is for a permanent hardware team member to work at the Thales Crawley Manor Royal site, within the Hardware (Electronics) discipline team. For full details online enter reference: JS1100107

www.totallyengineering.com/ne Part of the totally engineering network Sales: Darren Wright 01621 813393

As a Design Engineer, you will have a Degree in Electronic Engineering or Physics, with a bias towards analogue power system design or Power Supplies. You will have knowledge in Analogue Power Electronics, SMPS or ideally Low Power LED. For full details online enter reference: JS00037

Charging ahead In order to provide the desired lifetime and charge cycles, electric vehicle batteries must be managed carefully. By Greg Zimmer.

22 November 2011

Fig 1: The basic topology of a high cell count EV/HEV module

12 cell battery modules Current sensor

–

Battery monitoring and balancing

Service switch

or hybrid (HEV) and full electric vehicles (EVs), Li-Ion batteries offer the best trade off of power, energy density, efficiency and environmental impact. But Li-Ion batteries can be delicate and dangerous, while automobiles can be cruel and unforgiving. The challenge is to bridge the gap between the two environments. Operating large Li-Ion automotive battery packs safely and reliably is not simple. The capacity of Li-Ion cells will degrade when operated to a full state of charge or discharge, while charge cycling, lot to lot differences and different environmental conditions mean battery cell capacities diminish and diverge over time. Thus, to meet a 15 year, 5000 charge cycle goal for a battery pack, each cell must be kept within a limited operating range. By controlling each cell’s state of charge (SOC), a battery pack’s capacity can be maximised and degradation minimised. The battery management system (BMS) ensures the safe and efficient use of the vehicle’s battery pack. The BMS tracks and controls the SOC of each cell – discharging cells or moving charge such that cell voltages are matched and within a specific range. Measurement accuracy is critical; it determines how close each cell can be operated to the edge of its reliable SOC range. The ability to maximise usable capacity determines the number of battery cells needed, with cost and weight implications. Measuring the voltage of every cell accurately is difficult because battery pack cells are subjected to high common mode voltages and high frequency noise. To understand, consider that EV/HEV battery packs typically comprise a group of 100 to 200 cells connected in series. These packs must deliver charge and discharge currents that can exceed 200A, with voltage transients potentially exceeding 100V at the top of the stack.

Data bus Host CAN controller SPI

–

Contactor

–

Driven by cost and reliability concerns, automotive electronics is moving to higher levels of integration and reduced component count. This is especially true with BMS electronics, where highly integrated devices are emerging as the key data acquisition component. The battery monitor’s primary function is the direct measurement of series connected battery potentials, typically 12 channels per IC. Other functions include cell balancing control and additional measurements, such as temperature. To handle a high voltage stack, these devices typically communicate via a daisy chained serial interface. One element of the BMS, typically not

–

integrated, is embedded software. The SOC algorithm is highly guarded, specific to the chemistry, size, form factor, operating conditions and application. Figure 1 illustrates the basic configuration of an arbitrary cell count battery module, where the BMS algorithm is software coded and controlled by the developer. A critical consideration is how battery montoring ICs handle noise. For example, many battery monitors use a fast successive approximation register (SAR) converter for cell digitisation. While this might seem advantageous in a data acquisition system with more than 100 channels, the noise environment

www.newelectronics.co.uk

Research & Development Analogue Design

requires significant filtering and this determines effective throughput, not sampling rate. For this reason, a Delta-Sigma (DS) ADC offers better performance. For a given amount of 10kHz noise rejection, a 1ksample/s DS a/d converter provides a throughput equivalent to a 1Msample/s SAR a/d converter. For example, the LTC6802 uses a 1ksample/s DS a/d converter that can sequence through 10 input channels in 10ms. A built in linear phase

interface to a microprocessor or control unit. The second option features individually addressable serial interfaces. Here, a microcontroller communicates via isolation with multiple devices in parallel. This topology offers the inherently more reliable ‘star configuration’: loss of communication with one device does not eliminate communication with any others. Addressable devices can also be used in a modified daisy chain topology, where

Fig 2: LTC 6803 block diagram

Second reference

Regulator Decoder check Watchdog timer

Open wire check Digital filter check

Multiplexer

Delta Sigma a/d converter

Results register and communications

Reference

Control Die temp

Ext temp

digital filter provides 36dB of rejection to 10kHz switching noise. By contrast, a 1Msample/s SAR converter requires a single pole RC filter on each cell, with a corner frequency of 160Hz, to get the same noise rejection at 10kHz. The 12bit settling time of the RC filter is 8.4ms so, even though a SAR can sequence through 10 channels in 10ms, scanning more than once every 8.4ms is pointless because of the filter’s response. Given the long chain of battery monitoring ICs, the serial interface is also important and Linear offers two options. One option, supported by most battery monitoring ICs, is the daisy chained interface in which each IC in the chain communicates to its neighbour without optocouplers or isolators: only the bottom devices

www.newelectronics.co.uk

relatively expensive isolators are replaced with a less expensive ‘transistorised’ SPI bus configuration. The result is a serial interface with a wide compliance range. After two years of production, Linear has introduced a second generation device: the LT6803. A comparison of the first and second generation devices offers insight into the direction of future high voltage battery systems. One of the goals of the LTC6803 is to ensure error free communications, even under the most extreme noise. Packet error detection is implemented for all commands and data to ensure communication integrity. The LTC6803 family continues to support daisy chained and individually addressable serial communications

and the LTC6803 daisy chain can be subjected to more than 20V of ac noise and 30V of fast switching spikes with no errors. Its independent supply input can be disconnected while leaving other connections intact. In this hardware shutdown condition, the LTC6803 draws only a few nanoamps; important for long term battery pack storage, since the current consumed by the integrated BMS can potentially unbalance the cells in a battery pack. The LTC6803 can also be operated from an independent power supply, allowing the supply current to be drawn from a separate source, instead of the battery pack. With a separate power supply, the LTC6803 can continue to monitor a stack of cells, even when all cell voltages have collapsed. Increasing electronic content in cars is driving new standards in automotive electronic quality and reliability, hence, the emergence of automotive electronic standards such as AEC Q100 and ISO 26262. This translates to extensive qualification and internal capability to ensure that system safety requirements can be satisfied. The LTC6803, designed for ISO 26262 compliant systems, includes an open wire check, digital filter check, multiplexer decoder check, watchdog timer and a redundant voltage reference for full self test capability (see fig 2). A number of other improvements are included to address demands outside of the standard automotive design. For example, the part has an extended measurement range – from -300mV to 5V – to support supercapacitors and NiMH batteries. It is specified for operation from -40 to 125°C and has been designed to withstand supply voltages up to 75V. The automobile is a tough environment for electronics, but increased automotive electrification is not up for debate. Lithium-Ion battery systems in EVs and HEVs will soon become mainstream and sophisticated measurement devices, such as the LTC6803, are essential to their success. Not only must these devices be accurate, they must also operate reliably operate for long periods under difficult conditions. Author profile: Greg Zimmer is senior product marketing engineer, signal conditioning products, for Linear Technology. www.linear.com

22 November 2011 35

High-Precision DC Power Supplies Customised high performance power supplies for HIGH CURRENT and HIGH VOLTAGE

Heinzinger develop and produce high-precision and technically challenging power supplies of very high capacities, very high voltages and support for operation in multiple quadrants. The latest addition to the Heinzinger range is the superb ERS systems. Offering up to 1200V and >200kW of highly responsive bi-directional DC power for battery test, super-cap test, battery simulation and other high power component testing. When acting as an electronic load, energy recovered from the load is returned to the AC mains, signiﬁcantly reducing energy costs.

• • •

Bi-directional power supply High voltage (to 400kV) High current (to 10kA)

• •

High power (to 500kW) Precision power supply (<10ppm stability)

…available from PPM Power call +44 (0)1793 784389 or visit www.ppmpower.co.uk THE POWER IN POWER ELECTRONICS

Manufacturers of RFI/EMI gaskets, components & Environmental seals.

Over 30 years experience in providing solutions to emc and environmental sealing issues.

www.kemtron.co.uk

+44 (0) 1376 348115 · info@kemtron.co.uk

22 November 2011

www.newelectronics.co.uk

Embedded Design Embedded Test

Getting on the bus How a general purpose oscilloscope can help with low speed serial bus debugging. By Tom Schmidt.

sing an oscilloscope to analyse and debug a low speed serial link is standard fare and today’s general purpose digital oscilloscopes contain a variety of features that allow the user to quickly verify a link or to troubleshoot a faulty system. Serial decoding packages are great tools for functional verification, but may not help to isolate a parametric problem on the bus. Also, users may not need to jump to the serial decode application in order to get a specific measurement. Is there any activity? When first turning on a system or troubleshooting a faulty board, a user will want to know if the bus signal(s) toggled when the switch was flipped or when a routine was executed. Roll mode, a simple but under used oscilloscope feature, provides a quick indication of signal activity without having to set up any trigger. Roll mode with peak detect provides confidence that signals as narrow as 500ps will be captured. Figure 1 shows a spi bus used to program a PLL circuit with three words during a power up sequence. The oscilloscope is set to roll mode at 200ms/div in peak detect acquisition mode. The peak detect circuitry is running at 4Gsample/s and storing min/max pairs at 250ksample/s. Power is applied to the board and the acquired data shows three separate packets of activity on all three bus signals. If the user desires to trigger in normal acquisition mode while looking for activity, the trigger type ‘OR’ – available in the InfiniiVision 3000-X series – can be used. With this trigger type, either or both slopes of any of the available trigger source can be enabled. For example, both rising and falling edge slopes on channels 1, 2 and 3 in fig 1 could be enabled. This trigger is useful because it is a functional

www.newelectronics.co.uk

Fig 1: Three packets of activity can be seen on three bus signals

‘or’ of channel edges, not a logical ‘or’ of trigger comparator states. This means a high level on an enabled channel will not mask triggers from other enabled sources. How many clocks? Often, users will want to count the number of clock cycles or edges in a packet from a serial bus that contains a dedicated clock such as spi, µWire or i2c. Fortunately, most general purpose ‘scopes provide two methods of getting this information. The first is to use the measurement system to count edges, pulses, or both. The captured burst will measure the number of clock cycles (and edges) of a long register programming stream; for instance, into an fpga. Automatic measurement markers provide confidence by indicating the first and last pulses. The other method is to use simple trigger sequencing. The user can measure the number of edges indirectly or trigger on a specific clock

edge within a packet by using this sequencing. For example, in the 3000-X series, the mode ‘Nth edge burst’ is useful for triggering on a non continuous clock signal. In this mode, the trigger system must first find a period of no activity on the signal. This time is set by the ‘idle’ control softkey, which has a range from 10ns to 10s. After the idle time requirement has been met, the trigger will occur on the desired edge count within the pulse stream. This count can be set from 1 to 65,535 by using the ‘edge’ softkey. The slope can be rising or falling. For example, the oscilloscope will trigger when the count is set to 540 or less, but not if the count is set to 541. For systems with continuous clocks, the ‘edge then edge’ mode can be used to trigger on a specific clock edge. In this mode, the trigger system sequences much like ‘Nth edge burst’ but, instead of looking for an idle, the system looks for an edge such as a chip select in a spi bus.

22 November 2011 37

Embedded Design Embedded Test

Know your scope’s update rate General purpose scopes are, first and foremost, viewing tools. Having a scope that gets data to the screen with minimal dead time is invaluable when viewing waveforms and spotting problems. Fig 2 shows an spi bus clock from a system that exhibits periodic failures. At first glance, the signal looks normal and the user is tempted to look elsewhere to find the issue. However, putting the scope in infinite persistence mode and allowing the waveform to build shows an intermittent glitch (fig 3). The ability to see the glitch is solely down to the scope’s ability to get data to the screen. For example, a scope that updates at 1million waveform/s will show that elusive glitch 1000 times more quickly than a scope that updates at 1000waveform/s. The median time for the glitch to be captured is approximated by the equation: 1 / (scope update rate x screen time x signal rate) which, in this example, is: 1/(106 x 20ns x 20Hz) = 2.5s A scope which updates at 1000waveform/s would have a median time of 41mins. Once the glitch is seen, it is important to trigger on it to correlate with system events. Specialty trigger types – such as glitch, runt, setup/hold and transition time – may be useful here. Probing Poor probing can obfuscate the verification process, leading to wrong answers and

Fig 3: Infinite persistence mode can capture an elusive glitch

22 November 2011

Fig 2: At first glance, this spi bus clock from a system that exhibits periodic failures looks normal

increased debug time. In general, it is best to have the shortest ground lead possible when using a single ended probe while making parametric measurements. Not only does a long ground lead decrease the bandwidth of the probing system, but measurements are also susceptible to circuit noise, ground bounce and esd. When probing, the user can be fooled into thinking there is a problem in the circuit when there is none. To determine how much background noise might be seen with a given probing configuration, probe ground on the target (both

probe tip and ground lead connected to the same node on the DUT). When it comes to esd and other non circuit noise, the probe with the long ground lead is very susceptible. It is easiest to see this by putting the trigger mode to normal and setting the trigger level above or below the baseline level. Most users of low speed serial bus decoding know that getting time aligned information is most useful for two measurement scenarios: bus content verification; and correlation with other system signals and events. With this in mind, the signal requirements for the decoder are different than for parametric measurements. With the possible exception of i2s and spi, most serial bus clock speeds or bit rates are sub MHz. Allowing the scope to acquire these signals at full bandwidth is undesirable when the bus parametrics have been verified and are not of concern. So put the measuring channel(s) into BW limit; not only will this help to minimise the scope’s inherent noise, it will also reduce the effects of using long ground leads. Knowing your oscilloscope’s capabilities and features can greatly reduce the time you need to use it. With the right toolset, you can quickly verify operation or locate a problem. Author profile: Tom Schmidt is the triggering and hardware assisted serial decoding architect for Agilent’s InfiniiVision oscilloscope range. www.agilent.com

www.newelectronics.co.uk

The S-Series Aeroflex introduces the signal generator of the future, and makes compromise a thing of the past. With a legacy of innovation that includes pioneering the use of Fractional-N synthesizers originally developed by Marconi Instruments, Aeroflex sets a new standard for performance, versatility, and ease of use with the SGA analog RF signal generator. Compact and lightweight with an intuitive touch-screen interface, the SGA offers best-in-class precision, productivity, and reliability — all at a surprising mid-range price. •

Test both high quality receivers and devices faster. Typical phase noise is -135 dBc/Hz at 20 kHz offset from a 1 GHz carrier. You can easily measure receiver selectivity beyond 80 dB.

•

Accelerate production throughput. Frequency settling times range from 1 ms to 100 µs — up to 5X faster than comparable signal generators.

•

Have answers at your fingertips, not buried in menus. The elegant touchscreen interface requires fewer commands, saves time, and prevents errors.

www.aeroflex.com

www.newelectronics.co.uk

22 November 2011 39

Quality networking A UK start up has developed a way of ensuring service quality on congested networks. By Roy Rubenstein.

acket based networking has become the standard way to deliver communication services. But the very success of packet networking is challenging telecom operators in how they support the varied requirements of the services carried over their networks. Indeed, some industry voices question whether the internet economy is sustainable, given the rate at which IP traffic is growing. UK start up Predictable Network Solutions has developed technology that it claims ensures the performance of applications in the face of network congestion. The approach promises to save operators money by enabling them to load their networks more efficiently. It also promises operators new revenues by enabling them to provide – and charge for – services delivered with real time assurance. “This [solution] came about by asking questions,” said Neil Davies, cofounder of Predictable Network Solutions (PNS). “How do you ensure applications when networks are saturated? And how do you make sure money is made from networks in the long term?” According to Davies, operators tackle traffic load by adding excessive network capacity – ‘throwing bandwidth at the problem’. However, this has a knock on effect on the delay, and even the dropping of IP packets over the network. And it is packet delay and loss that dictate a service’s performance, especially when the packets carry voice or video data. “Managing bandwidth to manage traffic load establishes a relationship between loss and delay and operators do not manage [these parameters],” said Davies. In fact, he says that, by managing bandwidth, packet loss and delay are made worse, causing quality to degrade. Instead, PNS’ approach is to control quality degradation, what it calls quality attenuation. “Quality attenuation is the combined effect of [packet] loss, delay and jitter,” said Davies (see fig 1).

22 November 2011

Fig 1: The decrease in quality is an additive function

∆Q1

WAN

LAN

∆Q0

∆Q3

LAN

∆Q2 ∑ ∆Q

Quality attenuation comprises three elements: the distance between the transmit and receive points; packet size – bigger packets take longer; and the effect of other traffic streams on the transmitted one. The distance between end points and packet size are largely fixed and dictated by the technology. What can be controlled is contention, says Davies. There are certain points in the network where a packet stream encounters congestion along with other streams. This is a consequence of the way packet networks work: when more traffic is present at a node than can be sent, traffic streams are queued and prioritised at the switching or routing node before being sent on. PNS’ technology manages the contention a stream will experience before the traffic even enters the network. “We apply the policies all at one point,” said Davies. “We do that based on what loss and delay characteristics you want for your traffic to achieve an outcome.” Clearly, unless the technology is implemented at all the network’s entry points, a stream will encounter traffic that has not been

so treated. But that is not an issue, so long as the network has predictable, sustainable quality attenuation properties. And operators’ networks largely have such properties. The company characterises a network in terms of overall loss/ delay. Taking that into account and controlling the congestion for each stream it processes, PNS can control quality attenuation. Using two ADSL modems over BT’s network, for example, the end to end delay budget for voice is 150ms. “You need 60% [of the budget] just to get out of the premises, 30% to get into the premises at the other end, and 10% across the core network,” said Davies. As long as the ADSL modem does not overdrive the network, the BT network will not try to shape – or rate limit – the stream. And it is such traffic shaping that introduces undue delay; enough to destroy VoIP call quality. “We avoid any traffic management policies being imposed [on the stream by the network provider] by preshaping the traffic,” said Davies. “We’ve found the core is predictable; there is

www.newelectronics.co.uk

Communications Design Communications Hardware

Fig 2: Main contention points in the network architecture Downstream contention points

Legacy ATM network service provider

Network service provider 1

Upstream contention points

ATM

Layer 2 tunnelling server

Network service provider 2

Broadband remote access server

ATM

Access node

Main distribution frame

Network interface device

User 1 Residential gateway User 2

Network service provider 3

Access network

Customer premise network

Regional broadband network

a bound on the delay, jitter and loss that it introduces to packet streams flowing across it,” he said. “However, this only applies if you stay within the ‘predictable region of operation’ for that infrastructure. For an ADSL operator, it means avoiding a rate limiter in the broadband remote access server; for other operators, it means avoiding falling foul of their heavy user management system. We make sure the composite traffic stream has that property.” Network topologies tend to be tree like, he says, such that if the properties of the contention points of the paths to the destination are known, all that shaping can be brought back and used before the packets are introduced to the network (see fig 2). “They are spaced in such a way that they never contend with themselves down the line,” said Davies. But that requires contention to be worked out and broken down, based on the individual links. “You don’t have to solve this end to end; you can solve it hop by hop,” said Davies, “and this is relatively straightforward.” Operators’ networks have a well understood,

www.newelectronics.co.uk

relatively fixed configuration and, while there may be redundant paths, networks don’t change very often. “[The nature of] BT’s network hasn’t changed in six years,” said Davies. For the ADSL example, by using PNS’ traffic preshaping, the upstream’s traffic’s variability is limited to less than 5ms of the 15 to 20ms budget. PNS performs traffic preshaping using a low cost scheduling algorithm implemented in software. Hardware acceleration, using an fpga, is only needed for data rates in excess of 10Gbit/s. “This is an edge device,” said Davies. “We also have a device – a contention manager – that sits in the centre of the network.” Because the network topology being connected to is known, the biggest streams the contention manager must process are some 200Mbit/s. “You can have a rack of contention managers, each taking a portion of the [routing table’s] traffic,” said Davies. “It forces all the contention to occur at the contention manager, which then manages it.” PNS has developed a suite of software tools to measure a network’s quality attenuation

performance. It is providing consultancy to operators, large enterprises and government agencies to assess their networks’ performance. BT has evaluated the technology and is using it in trials for specialist services. Davies admits that it has been hard to sell the concept to operators, partly because they believe their networks are working fine and delivering quality service. “People don’t believe they have a problem, although they do,” he said. But what Davies says the technology has shown is that operators are continually upgrading their networks prematurely. “We are helping companies by providing measurements that show they are running their networks at very low utilisations and upgrading very early, otherwise they can’t cope with the operational problems they incur.” Tackling quality attenuation is also a must as consumers connect more devices – such as femtocells – to their broadband. “I can make small cells work over ADSL,” Davies concluded. “I’ve got one over the top of the house serving the village.”

22 November 2011 41

For more information on the following jobs enter the reference No. on... www.totallyengineering.com/ne

Principal Engineer, Analogue/RF IC Design

ASIC Verification Expert

Type: Permanent Salary/Rate: £50k-£65k per annum + benefits

A leading Cambridge consulting firm is currently recruiting for experienced digital verification professionals with excellent experience of System Verilog for a 6-month contract opportunity. Successful applicants will be responsible for the development of leading-edge verification methodologies and ideal candidates will have significant experience with ASIC/FPGA verification. Essential Skills: • At least 5 years’ experience verifying IP for large-scale ASICs and SoC for commercial products • Excellent knowledge of VHDL and Verilog • Significant experience in testbench design, using transaction level modelling and System Verilog language • Experience of code and functional coverage • Knowledge of Scripting languages, particularly Perl.

Cambridge, Cambs

An experienced Analogue/RF IC Design engineer is required for an experienced Principal Engineer role with a market leader, working within the wireless communication sector.As a principal engineer, your role will be to act as a key contributor to the design, implementation and verification of the company`s chips. In addition to contributing to the specification design and verification of entire chip sub-systems using appropriate tools, you will also contribute to chip level architectures, and the definition of new features and market-driven enhancements. This is a unique and exciting opportunity to join a world leader in its field in a senior role, where you can immediately help shape the development of the company’s development. As well as the chance to assume a leading role within a dynamic working environment, you will also have the opportunity for real further career progression, and be offered a highly competitive salary and package. For full details online enter reference: JSCAM//899

Senior DSP Engineer Location: Cambridge, Cambs Type: Permanent Salary/Rate: £45k-£50k per annum + benefits A rare opportunity has arisen for an experienced DSP Engineer to work in an exciting and established young company, working within the consumer electronics sector. In the position of Senior DSP Engineer, you will immediately have the opportunity to play a leading role, working on the company’s cuttingedge technology. The work is varied and will include algorithm development, modelling, software development and integration, systems engineering, test and debugging, and involve the use of high-level modelling languages, such as Matlab, and implementation in C and Assembler.

Location: Cambridge, Cambs Type: Contract Salary/Rate: £40-£45 per hour

For full details online enter reference: JS-.ASICSYSVERCONTCAMBS

Embedded Software Engineer Location: Derby, Derbyshire Type: Permanent Salary/Rate: £35k-45k per annum Job Details: With over 30 years’ experience in the design and development of complex automotive electronic systems. My client is one of the leaders in the automotive industry. They work with a wide portfolio of electronic systems ranging from electronic seat control to keyless and passive entry systems. Your role in the company will be developing new electronic systems and upgrading existing ones. You will be working the most up to date cutting edge technologies available. Working with an award winning engineering team.

Senior Electronic Design Engineer Location: Staffordshire Type: Permanent Salary £ 40k-£50k per annum Job Details: Alstom Grid Senior Electronic Engineer. Looking for a candidate with solid experience of the full hardware development lifecycyle. The successful candidate will have covered one of the main areas of Electronic Design and Analysis, Digital and Microprocessor, Analogue and Power Supply, or Embedded software. In terms of Analysis, the role will require the successful applicant to have had experience with certain areas, such as Failure Modes Effects Analysis, Fault Tree Analysis, Parts Stress Analysis, reliability and Calculation. FPGA Design skills will also be necessary, with the ability to program devices using VHDL.

For full details online enter reference: JS-.1118

Electrical Wiring Technician (Manufacturing) Location: Templecombe, Somerset Type: Permanent Salary/Rate: To be advised Thales Underwater Systems creates a wide range of products & systems for submarines, surface vessels, mine-countermeasures vessels, and aircraft, including hull-mounted, variable depth, towed & dipping sonar systems, sonobuoys & sonobuoy processing systems, torpedo homing heads & antennas, & sonar support systems. We're looking for an Electrical Wiring Technician to join our busy manufacturing team. The role will involve the assembly of electro-mechanical assemblies and their sub assemblies, as well as the assembly of Backplanes, Wiring Harnesses, Cable Looms and Connectors. You'll also be responsible for modification of existing equipment including PECs.

This is a great role, which will offer an experienced candidate the opportunity to play a leading part in the continued development of the company’s market-leading products.

ESSENTIAL SKILLS FOR THE EMBEDDED SOFTWARE ENGINEER ROLE: • EMBDEDDED CONTROL SYSTEMS • PROGRAMMING LANGUAGE C • MICROPROCESSORS 8, 16 &32 BIT • LOW LEVEL DRIVERS FOR EXTERNAL HARDWARE/CPU PERIPHERALS • Real Time CONTROL • 5+ YEARS OF DESIGN IN A COMMERCIAL ENVIROMENT

Solid experience of electrical assembly within a production or development facility (or similar environment) and an appreciation of mechanical assembly would be an advantage.

For full details online enter reference: JSCAM//88

For full details online enter reference: JS-.4261(PEK)

For full details online enter reference: JS1104716

For this role, you will need proven DSP Engineering experience, as well as good Matlab and C programming skills. If you have knowledge of audio DSP, then this would be an advantage, but is not a necessity.

www.totallyengineering.com/ne Part of the totally engineering network Sales: Darren Wright 01621 813393

System Design Backplanes & Boards

On the platform How a VPX development platform can reduce time to market. By Martin Blake.

ew generations of embedded computing systems based on the VPX standard reflect the growing significance of high speed serial switched fabric interconnects. These are replacing traditional parallel communications bus architectures for local communications because of their increased performance. Switched fabrics also provide an optimum way to support the implementation of multiprocessing systems, such as digital signal processing applications that require the fastest possible communications between multiple processors. VPX (VITA 46) is a VMEbus based standard that retains VME’s existing 3U and 6U form factors and adds support for switched fabrics over controlled impedance, low crosstalk 6.25Gbits/s connectors, with boards typically spaced on a 1in (5HP) pitch. Developed primarily to increase the I/O capability and bandwidth of VME, it supports high speed serial interconnects, such as PCI Express, RapidIO, Infiniband and 10Gbit Ethernet, while maintaining the maximum possible backwards compatibility with VMEbus. As well as the switched fabric interface, VPX also supports PMC and FMC (VITA 57) as mezzanine cards and XMC (VITA 42) via an additional P5 connector. Hybrid backplanes to accommodate VME64, VXS and VPX boards are also specified to maximise backwards compatibility. As the VPX specification evolved, the baseline electrical and mechanical VITA 46.0 standard was rapidly augmented with a further 10 ‘dot level’ specifications, moves which created a range of application specific – and potentially non compatible – options. Given that each top level ‘dot’ specification defines a considerable

www.newelectronics.co.uk

The 3U TecSYS VPX development platform is housed in a 10.5in half width 6U Diplomat enclosure

number of standard alternatives, the fundamental benefits of standardisation were soon lost in the overwhelming number of possible options. As VPX has evolved from VMEbus, it has been designed into a number of high profile military programs. Responding to pressure from military users to bring a compatible set of draft specifications to finalised status, the OpenVPX working party, consisting of some 30 companies, was formed. This body developed OpenVPX (subsequently published as VITA 65) in response, bringing a limited number of system topologies to completion. However, while OpenVPX compliant systems are a small subset

of the total available number of options, it still allows for several thousand possible alternatives. While relevant for the ruggedised environments to be found in military, transport and aerospace applications, full OpenVPX compliance is not generally necessary for commercial applications. OpenVPX is a system level specification, defining additional thermal management, EMC, shock and vibration immunity requirements, in addition to the fundamental VITA 46 electrical and mechanical requirements. OpenVPX defines the technical implementation details for 3U and 6U VPX payload and switch modules, backplane topologies and chassis configurations to provide clear guidance on how to build interoperable computing and communication platforms. Increased capability invariably leads to higher power requirements. A VMEbus slot is limited to a maximum of 90W at 5V; VPX raises this to 115W at the same voltage, up to 384W at 12V and 768W at 48V. To manage issues arising from higher power levels, VITA 48.0 – also known as REDI, Ruggedised Enhanced Design Implementation – calls for ESD metal covers on two sides of VPX boards and allows for forced air, conduction and liquid cooling implementations. Like OpenVPX, conforming to REDI is, arguably, a step too far for the development environment and for systems deployed in purely commercial applications.

22 November 2011 43

System Design Backplanes & Boards

A number of manufacturers have announced products based on the VPX standard, in both 3U and 6U form factors. These include single board computers, based on both Intel and PowerPC architectures, multiprocessors, graphics processors, fpga based processing modules, mass storage, switches and complete integrated subsystems. A potential constraint to the wider use of VPX systems has been the lack of a suitable entry level development platform that provides a basic physical environment for software development and board integration. Feedback from Verotec’s customers, who are investigating the potential of VPX for non military systems, showed that, while most applications may eventually require a custom backplane, there is a distinct shortage of a ‘basic’ hardware platform. To address this gap in the market, Verotec has introduced the TecSYS VPX development platform. A modular system assembled from standard building blocks, TecSYS is user configurable around the default options if required. The 3U TecSYS VPX is housed in a 10.5in half width 6U, 322mm deep Diplomat enclosure. This is configured with a 2U plenum chamber at the bottom, a 3U KM6-RF subrack in the middle and a 1U air exhaust chamber at the top. At the heart of the system is a five slot 3U full mesh X4 PCI

At the heart of the system is a five slot 3U full mesh X4 PCI Express VITA 46.4 backplane

Express VITA 46.4 backplane. There is also a VITA 46.10 rear transition module, an important consideration for I/O, that can be accessed readily through a removable rear panel. Meanwhile, the top cover is removable for improved access. The backplane provides system management and boundary scan interfaces. This configuration gives ‘fat pipe’ communications between all five slots and provides an interface with PCI Express, one of the most widely used architectures. Power for the main rails – +3.3V, +5V and +12V – Blake: “A potential is provided via M4 studs, each rated at constraint to the 40A. This gives some wider use of VPX headroom above the systems has been VITA 46.0 maximum of 36A per slot. While the lack of a designed initially to suitable entry level meet the needs of the VPX development development community, TecSYS’ platform.” modular, scalable design enables it to be used for developments

22 November 2011

based on other 3U and 6U bus structures, such as VMEbus, VME64 and cPCI. Up scaling is simple: if a 6U system is required, the case size is increased to 9U, the pluggable power supply increases to a 6U version and the backplane, conforming to any of the standard bus structures, changes to a 6U form factor. Thermal management implementation remains the same, there are no non recurring engineering charges and delivery times are short, reducing time to market. System power is provided by an auto ranging PFC modular pluggable power supply fitted with a standard PICMG 47pin connector. The supply connects into a power interface board, which feeds power to each slot’s M4 stud. The 300W supply features two independent converters operating in parallel, enabling it to provide 30A at 5V and 40A at 3.3V simultaneously. Thermal management is provided by two dc fans installed below the subrack to give bottom front to top rear forced ventilation for the power supply and system boards. If required, additional fans can be mounted at the top of the rear panel to give push-pull cooling. The 2U front panel is fitted with power and fan indicators and an ESD wrist strap bonding point. In addition to the development environment, TecSYS is portable, compact and quiet. Its attractive appearance enables it to be used as the enclosure for target systems and at exhibitions and customer demonstrations While most VPX systems will benefit from a custom backplane to enable them to operate to their full potential when they migrate to volume production, the TecSYS VPX development platform provides a real world environment for software and hardware design during the development phase of the project. Author profile: Martin Blake is technical applications manager with Verotec. www.verotec.co.uk

www.newelectronics.co.uk

To help your 2012 planning, download the O.UK ICS.C TRON ELEC .NEW WWW

Overview

ew Electronics media pack and editorial programme from

Advertising

RMAT

Editorial

magazine The ONLY trying to for anyone electronic reach the tor. design sec

.co.uk www.newelectronics

24 November

The magazine

for electronic

SOUR

R CE FO

ELECT

RONI

IG C DES

Reader Surve

GI N EN

NEER

ces

Contract Servi

Direct Marketing

Online

UK gy news to t technolo the lates bringing agement. s has been Electronic design man years, New electronic ysis, neers and For over 40 htful anal ronic design engi es and insig (UK’s) elect electronic cover stori reach the epth to g in-d features, anyone tryin lar news, azine for With its regu s is the ONLY mag ency, its ronic ightly frequ also New Elect h – its fortn can r. azine in dept rial programme. You design secto et at the mag edito target mark s you to look its focused to reach your ia pack allow ted circulation and allow you This med targe able that and avail ed ns well defin t the optio ares all the more abou e and comp discover tion to mak et survey ision. the best posi latest mark with prec you are in using our that ence so ts, with evid ides you and BPA audi . etitor ABC It also prov campaign ant comp current relev ce for your marketing choi t righ the you. ing with ard to work We look forw

ION

Circulation

2009

design engineers

BATTERY PACK WILL A CUSTOM PRODUCT? PORTABLE SUIT YOUR FAB TO ANALOGUE FIRST 300MM PERFORMANCE BOOST PRODUCT TACKLE PROCESSORS NETWORK CHALLENGES GROWING ACCESS

Y Y/INDUSTR UNIVERSIT ATION PUSHES COLLABOR FRONTIERS GY TECHNOLO

www.newelectronics.co.uk/new-electronics-magazine/

Download PDF catalogues or apply for your free 300pp print handbook today

NFO THE I

Email:

• • • • • •

Peter Ring r Publishe uk indlay.co. E: pring@f 44 2211 T: 01322 s.co.uk electronic www.new

O.UK ICS.C TRON ELEC .NEW WWW

2 221144 (0) 132 .uk T: +44 ndlay.co

pring@fi

Subracks and Enclosures Instrument Cases 19” Racks and Accessories Backplanes and Power Supplies Integrated Systems Thermal Solutions Contact us. t: 023 8024 6900 sales@verotec.co.uk www.verotec.co.uk

VERO

VERO VERO – APW – APW – VEROTEC – VEROTEC. Continuing Continuing 50 years 50ofyears excellence of excellence in enclosure in enclosure design and design manufacture and manufacture KM6 • Diplomat • Eurotec Case • Verotec • fan trays • LBX • Total Access Case • rack cases • IMRAK • backplanes Electronics Packaging

Marketwatch Component Prices

Analysis CATEGORY

DESCRIPTION

AUG

SEP

OCT

Analogue Monolithic

Amplifiers and comparators

-0.3

-0.6

-0.7

Analogue Monolithic

Analogue interface ics

-0.3

-0.6

Analogue Monolithic

Voltage regulators and references

-0.3

-0.6

Capacitors

Aluminium

-0.1

-0.4

Capacitors

Ceramic

-0.6

-0.9

-0.6

Capacitors

Tantalum

-0.7

-0.8

-0.6

0.6

0.4

0.9

-0.8

-0.7

-0.2

-0.4

Connectors Resistors

SMD flat chips

Filters Crystal

kHz

-0.3

-0.8

Crystal

MHz

-0.4

-0.6

Oscillator

TCXO

-0.6

-0.7

Oscillator

VCXO

-0.3

-0.8

-0.7

Oscillator

-0.4

-0.5

Magnetics

Ferrite beads

-0.4

-0.3

Magnetics

Fixed inductors

-0.3

Standard Logic

General purpose cmos

-0.9

-1.1

-0.5

Standard Logic

General purpose bicmos

-0.8

-1.0

-0.5

Standard Logic

General purpose bipolar

-1.1

-0.4

Rectifier

Schottky and ultrafast

-0.3

-0.6

-0.5

Transistor

Bipolar power

-0.4

-0.3

Transistor

Power mosfet

-0.4

-0.6

-0.4

Transistor

Small signal

-0.4

-0.6

-0.4

Memory

Dram

-4.6

-3.4

-4.2

Memory

Flash – NAND

1.8

1.0

-3.0

Memory

Flash – NOR

-0.8

-0.5

-6.3

PCBs

PCB manufacture

-0.3

Data courtesy of IHS iSuppli

Component prices were reset at zero in September 2007 and show percentage changes per month. Increasing prices are highlighted in red.

22 November 2011

Amplifiers/comparators The traditional segments that drive this market, such as computing and some elements of consumer electronics, are not showing typical seasonal demand. However, there is strong demand from the industrial and white good segments for energy efficient electronics, as well as from the mobile phone market. Logic products Demand for logic products remained strong in 2011, driven mainly by developments in the pc hardware, cloud computing, smartphones, industrial and automotive segments. According to IHSi Suppli, while leading companies have a negative outlook , prices are expected to stabilise and lead times to ease slightly. Ceramic capacitors Demand continues to be slower than expected, with the pc and mobile handset markets remaining soft. Inventories have increased to the point where any short term increase in demand can be met. Lead times and prices will continue to fall for most case sizes and capacitance values.

The IHS iSuppli mission is to reduce the overall cost of acquisition for electronic components, whilst improving the continuity of supply and simplifying supply chain processes for ems, oem and supplier communities. Market Intelligence Services provide critical information designed to enrich tactical decisions and strategic plans. Visit www.isuppli.com

www.newelectronics.co.uk

Call James Slade on 01322 221144

Technology Update

Buzzers

Avnet Abacus, one of Europe’s leading interconnect, passive, electromechanical and power distributors, has announced two new piezo electric buzzers from Kingstate Electronics Corporation via a Pan-European deal with the leading Taiwanese maker of piezo buzzers, magnetic buzzers, micro speakers, dynamic receivers, electret condenser microphones and earphones. Kingstate have 34 years manufacturing experience in the acoustic field. Kingstate’s KPEG1300S is a combined strobesiren alarm. The piezo electric buzzer measures 50mm high and with a diameter or 58mm. With Frequency 2.5KHz, it produces min. 100dB (typ. 105dB) at 12VDC/100cm. The unit also features six ultra-bright LEDs which can strobe with an intensity of 15,000mcd, providing an attention-grabbing visual as well as audible alarm. The KPEG1300S is RoHS-compliant and sealed to IP55.

New Archer 1.27mm pin headers from Harwin stocked in depth for rapid delivery Versatile, reliable, available Harwin, the leading hi-rel connector and SMT board hardware manufacturer, has announced that its M52 2.54 x 1.27mm pin header range – part of its Archer board to board connector system – is now available ex-stock, rather than being produced to order based on a customer’s selected pin height.. Available in through-board and SMT styles, many standard pin lengths can now be shipped immediately, increasing design flexibility. This versatile, cost effective connector system offers good performance and is intermateable with other similar systems. It is ideally-suited to applications including test & measurement, robotics, industrial, handheld and medical equipment. SMT versions are available on tape & reel packaging for automated assembly.

@: lisa.rees@avnet-abacus.eu ✆: +44 (0)1628 512940

@: bgreen@harwin.co.uk ✆: +44-2392 314 532

Connectors

Connectors TTI, Inc. appoints Volker Gerhardt as Product Development Manager, Connectors for Central Europe Extensive experience will help TTI meet challenging targets

Leading global connector manufacturer and supplier ITT Interconnect Solutions has announced that its PHD38999 connector which utilises its tunable size 22 fibre-optic termini has passed a series of harsh environment tests included in industry-standard M38999 specifications. These connections systems are used in demanding defence and aerospace applications, including vision systems, flight connectors and control systems.

TTI, Inc., the global distributor of Passive, Interconnect, Relay & Switch and Discrete components, has recently announced the appointment of Volker Gerhardt as Product Development Manager Connectors for Central Europe. Volker will work within the Connectors Supplier Management team, managed by Director John Sandy, to develop and drive TTI’s connector strategy within its Central European branches. Volker Gerhardt has worked in the electronic component industry since 1988 and with TTI since 1998. Previously he worked as a Semiconductor Measurement Engineer with IBM in Germany. He benefits from an extensive knowledge in electronic design as well as electronic product and distribution marketing throughout Germany. Volker has held several positions within TTI, most recently as Branch Product Manager in TTI’s Pforzheim location where he developed strong relationships with TTI’s broad range of e-mech and connector suppliers.

@: david.impett@itt.com ✆: +44 (0)1256 311556

@: sales@de.ttiinc.com ✆: +49 8142 6680 – 0

Innovative fibre-optic termini for use in defence and aerospace

New Heatsink Solutions

@: heatsinks@ablcomponents.co.uk ✆: +44 (0)121 789 8686

High-Speed Powerline Transceiver Ensures Reliable Broadband Powerline Communications in Industrial Environments HomePlug powerline transceiver operates in harsh industrial conditions up to +105°C and provides broad design flexibility. Maxim Integrated Products (NASDAQ: MXIM) introduces the MAX2982, the first broadband, HomePlug® 1.0-compliant, powerline communications transceiver for harsh industrial environments. The MAX2982 is highly integrated and offers significant design flexibility. An enhanced “Robust” mode provides a receiver that operates at -1dB signal-to-noise (SNR) to ensure reliable communications in the presence of noise. The device operates from -40°C to +105°C and is qualified under AEC-Q100-Rev-G for harsh applications. The MAX2982 is an easy-to-use, industrial, broadband powerline communications solution for automation and control, remote monitoring, energy management, wireless base-station control and monitoring, and local area networking (LANs). @: solveig.loesch@maxim-ic.com ✆: +49 89 85 799-561

Varistors

AVX Corporation, a leading manufacturer of passive components and interconnect solutions, has developed an advanced varistor designed for general ESD protection use in automotive circuits, including CMOS, bi-polar, and SiGe based systems. The AEC Q200-qualified Automotive StaticGuard Series varistor delivers low capacitance and the lowest specified leakage current available in the industry, ideal for high-speed signal lines. The varistor series provides bi-directional transient voltage protection in the on-state and excellent EMI/RFI attenuation in the off-state, while offering an ESD rating up to 15kV. @: pernickyj@avxeur.com ✆: +420 575 757 540

www.avx.com

Automotive varistor series from AVX delivers the lowest specified leakage current available

Benefit from a PCB layout team to work with your engineers PCB Portal have experienced IPC CID certified PCB designers

Allegro Orcad

Cadstar Altium

PADS PCAD

We supply PCB prototypes and production runs. All technologies.

email sales@pcbportal.com telephone +44(0)1543 276769

www.pcbportal.com

www.maxim-ic.com

ABL Components has introduced two new product ranges targeted at serving all the heatsink market needs: • A new suite of Ball Grid Array (BGA) heatsinks is now available with thermal tape, push pin and wireform attachment options. They are provided with flip-chip, push-pin and standard BGA designs. • The UK’s largest range of high performance heatsinks has been established, produced with revolutionary manufacturing techniques to maximize thermal performance. Heatsinks from ABL are usually available from stock, with small lot quantity options and technical support, including a new interactive website to simulate performance of all products and assist design.

Powerline Communications Transceiver www.abl-heatsinks.co.uk

ABL Launches Market Leading Heatsink Range

www.ttieurope.com

www.itt.com

High-density PHD38999 connectors and termini from ITT ICS pass harsh qualification test

www.harwin.com

Piezo-electric buzzers also feature bright flashing LEDs

Connectors www.avnet.com

Avnet Abacus offers new combined strobe and audible buzzers from Kingstate via Pan-European franchise

mouser.com

AS9120A Certified Distributor

Distributing semiconductors and electronic components for design engineers.

Authorised Distributor

mouser.com

Find It Here. Faster.

™

The Newest Products for Your Newest Designs

Global Authorized Distributor of Electronic Components

World-Class Local Language Technical Support

450+ Industry-Leading Suppliers

17 Website Languages and Currencies Available

No Minimum Order and Same-Day Shipping

2 Million Parts Online

United Kingdom Suite C, First Floor, Artisan Building Hillbottom Road, High Wycombe Bucks. HP12 4HJ T: +44 (0) 1494-467490 | F: +44 (0) 1494-467499 uk@mouser.com

Mouser and Mouser Electronics are registered trademarks of Mouser Electronics, Inc. Other products, logos, and company names mentioned herein, may be trademarks of their respective owners.

NE_22_11_20

Articles inside

Contract Manufacturing

Embedded Test

Comment

Engineering Design Show