automotive electronics issue-4 - baixardoc

POWER TECHNOLOGIES Battery monitors

SHOW REPORTAdvanced Automotive Electronics

TEST & MEASUREMENTMixed-signal oscilloscopes

TELEMATICSField service management

SAFETYAdaptive cruise control

www.automotive-electronics.co.uk

PRODUCTS + NEWS + DIARY

ISSUE FOUR 2012

CONTENTS

CONTENTS 3

www.automotive-electronics.co.uk issue four 2012 | automotive electronics

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ISSN: 1749-1819

Editor Steve Rogerson, [email protected]

Editorial Contributors: Clive Davis, Kelvin Hagebeuk, Hafeez Najumudeer, Mark Forrest, Siraj Ahmed Shaikh and Padmanabhan Krishan

Designer

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Advertisement Manager

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Publisher

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Automotive Electronics is available to readers in the United Kingdom not meeting the terms of control at an annual rate of £55. The overseas subscription rate is US$130. Automotive Electronics is published six times a year by MT Publications Ltd. All rights reserved. No part of Automotive Electronics may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying and recording on any information storage system without the written consent of the publisher. The publisher cannot be held responsible for loss or damage to unsolicited press releases and/or photographs. Views of contributors and advertisers do not necessarily reflect the policy of Automotive Electronics or those of the publisher. Printed in the UK by Hastings Printing Company Ltd.

4 News

11 Diary

12 AAE Report

Steve Rogerson reports from November’s Advanced Automotive Electronics conference in Daventry

18 Power Technologies

Steve Rogerson looks at Linear Technology’s claims to have raised the bar for battery monitoring

22 Test & Measurement

Clive Davis, Kelvin Hagebeuk and Hafeez Najumudeen discuss how instruments can evolve to meet the latest automotive challenges

26 Telematics

Mark Forrest talks about how investment in today’s field service management technology can help streamline business processes to lead to long-term efficiency, profitability and customer retention

30 Safety

Siraj Ahmed Shaikh and Padmanabhan Krishnan describe safety analysis carried out for adaptive cruise control

35 Product News

2526

31

36

4 NEWS NEWS 5

automotive electronics | issue four 2012 www.automotive-electronics.co.uk

EU launches e35m driver assist programmeTHE EUROPEAN Union’s Ar-

temis joint technology initia-

tive has launched a three-year

project to design and develop a

tool platform for embedded ad-

vanced driver assistance (adas)

systems. Started in September,

the Deserve project has the

backing of car makers Daimler

and Volvo.

There are a total of 26 com-

panies across nine countries

involved in the project, includ-

ing Bosch. Continental, DSpace,

Infineon and NXP. Total invest-

ment in the project is expected

to be around e35m.

The project aims to exploit the

benefits of cross-domain soft-

ware reuse, standard interfaces

and easy and safe integration of

heterogeneous modules to cope

with the expected increase in

function complexity. A modular

system is also better placed for

keeping costs down.

Partners in the project will be

looking to develop reference de-

signs and architectures to create

tools that can be engineered with

little effort. The design methods

and tools will support the intro-

duction of disruptive hardware

and software to allow trade-offs

between properties such as cost

and robustness.

Cost is important because

one of the goals of Deserve is

to make adas affordable in the

low-end car market.

“The sharing of software and

hardware resources will enable

higher levels of complexity to

be taken into consideration

without a proportional increase

in the price of the modules and

the vehicle,” said a statement

from Deserve. “Fast and signifi-

cant market penetration will be

promoted through relevant cost

reductions and Europe’s posi-

Car thieves caught by mesh network

SINCE ITS launch in March,

Tracker’s mesh network has led

to the recovery of more than

£4m of stolen vehicles. The net-

work uses vehicles fitted with

SVR units to identify stolen ve-

hicles also fitted with Tracker.

This brings drivers together to

create a nationwide network of

listening vehicles.

“Our latest figures show the

success of the Tracker mesh net-

work, with well over £4m of sto-

len vehicles recovered using this

new vehicle crime detection sys-

tem,” said Stephen Doran, man-

aging director of Tracker. “Cru-

cially, the Tracker mesh network

empowers drivers by allowing

their cars to be used as detec-

tion devices to help police and

Tracker combat vehicle crime.”

When a vehicle fitted with

Tracker Locate or Plant passes

any Tracker SVR equipped vehi-

cle that has been reported stolen,

it automatically sends a signal

with the location of the stolen

tion as a key player in the adas

market will be strengthened.”

Deserve aims to create a Eu-

ropean standard including me-

ta-models, methods and tools

for safety-critical hard real-time

adas development. It should pro-

vide an environment for design,

development, pre-validation

and even pre-certification of

software and hardware for adas

applications.

The project acknowledges that

multi-core architectures will

have to play a key role to reach

the necessary levels of perform-

ance and safety.

When two is better than oneThis underground car park has provided a good example of how well Aptina’s image coproc-essors work in automotive camera applications. The image on the right shows the building as captured using the firm’s AP0100AT image coprocessor and AR0132AT megapixel HDR (high dynamic range) sensor. The sensor performance is improved because the heat is lower when using a separate coprocessor chip. “Our automotive OEMs need to deliver multiple camera products quickly and efficiently,” said David Zimpfer, vice president and general manager for Aptina’s automotive business. “Meeting this challenge, Aptina created an advanced, flexible two-chip solution that combines megapixel resolution sensor support, superior image quality including HDR, and optimal heat dissipation.”

The AP0100AT and AP0101AT co-processors provide colour processing, auto-function support, noise reduction and adaptive local tone mapping to enhance HDR images. The AP0101AT is for digital surround view systems and the AP0100AT supports 185˚ fisheye lens distortion correc-tion, perspective correction and multiple view options such as split side view and triptych.

car – even if it is hidden in a ga-

rage, container or underground

car park. Both drivers are totally

unaware that the stolen vehicle

has been identified.

“Ninety per cent of stolen cars

fitted with Tracker are returned

to their owners and 80% of these

are recovered within 24 hours,”

said Doran. “But with the mesh

network’s ever-expanding web,

designed to catch car criminals,

we hope to recover more vehi-

cles faster than ever.”

Cantata 6.2

shines at AAE

QA SYSTEMS chose the Ad-

vanced Automotive Electronics

(AAE) conference and exhibition

(see page 12) for its first show-

ing of version 6.2 of its Cantata

unit and integration testing tool

for C/C++ embedded systems.

Including more than 30 sepa-

rate enhancements and over 40

fixes, Cantata 6.2 has been spe-

cifically developed to simplify,

further automate and speed up

the software testing procedure.

Cantata 6.2 is now also available

as a complete built-on Eclipse

development environment or as

a set of Eclipse-ready plug-ins

supporting the most recent four

Eclipse releases.

“Since our acquisition of the

Cantata++ product line from IPL

in March 2012 and our subse-

quent rebranding to Cantata,

we have been working hard at

developing the product to suit

the immediate business needs

of software developers,” said

Andreas Sczepansky, CEO at QA

Systems. “Specific industry sec-

tors such as aerospace or trans-

port have very precise standards

that absolutely must be met for

business critical and safety criti-

cal systems, making testing a

fundamental activity within any

software development.”

Graham chooses Masternaut for fleetsMASTERNAUT HAS been se-

lected by Graham Construction,

one of Ireland’s largest private-

ly-held building and civil engi-

neering companies, to modern-

ise fleet management processes

and deliver increased visibility

over vehicle deployment and

fuel usage.

The telematics provider will

install its driver performance

products into the fleet of vehi-

cles. Graham anticipates saving

at least 5% in fuel costs.

“Working with Masternaut

will give us much more detailed

reporting, fully automated and

configured to our needs,” said

Karl Teggarty, business man-

ager of Graham Construction.

“This will allow us to see where

the fuel bill is going – by that I

mean which vehicles are using

the most fuel, and how driving

styles contribute to higher fuel

consumption.”

The Greener Fleet product can

access data from the vehicle’s

Can bus that generates granu-

lar data insights into fuel con-

sumption and driver behaviour.

Measurements of vehicle depre-

ciation and cost per kilometre

are now also available.

“Masternaut was selected as

part of a competitive pitch proc-

ess,” said Teggarty. “We carried

out a trial period across a sam-

ple set of vehicles and were able

to achieve significant savings,

so we’re really delighted to be

rolling it out across the fleet.”

The real-time web-based

system replaces the need for

manual time and mileage sheets

– providing more sophisticated

and reliable reporting.

“Graham is really planning to

make the most of the function-

ality that the product offers and

the ability to customise report-

ing to deliver the insights they

need from big data,” said Martin

Hiscox, CEO of Masternaut.


Continental and Freescale team up on 32bitFREESCALE AIMED to

strengthen its

position in the

automotive mar-

ket with a string

of announcements

at November’s Elec-

tronica show in Mu-

nich leading with a

quad-core 32bit mi-

crocontroller that it has

jointly developed with

Continental.

Aimed at electronic brak-

ing systems (EBS) and chas-

sis control, the device contains

4.75Mbyte of flash memory,

256kbyte of sram and Conti-

nental’s fail-safe technology,

which meets the requirements

for ISO26262 Asil D and Sil3

according to IEC61508 applica-

tions.

“Freescale and Continental

have worked together for many

years and this is the first device

using a fault-tolerant system,”

first device in the family

integrates four e200z4

cores based on Power

Architecture technol-

ogy. This is claimed

to be the indus-

try’s first quad-

core automotive

MCU with two

pairs of cores

in redundant

lockstep.

“ D e v e l -

oping a quad-

core MCU based on Power

Architecture technology with

this level of integration, redun-

dancy and functionality rede-

fines innovation,” said Cornyn.

“The resulting device has the

potential to provide unprec-

edented levels of performance

and safety for new generations

of braking systems.”

Also announced at Electroni-

ca were the Qorivva MPC5777M

quad-core MCU aimed at engine

fuel saving applications, Xtrinsic

pressure sensors for automotive

engine control and green vehi-

cle applications, and an Xtrinsic

radar transmitter for automotive

active safety systems.

“The MPC5777M is our most

advanced powertrain control-

ler,” said Cornyn. “We have just

supplied samples to the first tier

ones for engine management

use.”

said Ray Cornyn, Freescale’s

vice president for automotive

microcontrollers.

The two firms have collaborat-

ed on a custom MCU programme

called Quasar (for quad-core

microcontroller for automotive

safety and reliability) designed

to provide the processing intel-

ligence for Continental’s next-

generation EBS products. The

Ray Cornyn: “Freescale and Continental have worked together for many years.”

Qorivva MPC5777M quad-core MCU

6 NEWS


Green Hills and Obigo join forces on web platform

GREEN HILLS Software and

Obigo, an HTML5 platform com-

pany, are working together on

products for automotive info-

tainment and digital instrument

manufacturers. Obigo products

go into automotive, IPTV and

mobile software, web applica-

tions and services.

The two companies will offer

Obigo’s HTML5 web products

integrated and optimised for use

with the Green Hills Integrity

rtos and secure Multivisor virtu-

alisation technology.

This will lets automotive info-

tainment and digital instrument

manufacturers bring scalable,

graphics-rich products to mar-

ket rapidly and with high levels

of security.

With more than 800 million

units fielded in the mobile indus-

try since 1998 and licensed for

use in the commercial automobile

market since 2001, Obigo brings

the browser market to Green Hills’

customers. The HTML5 platform

consists of an HTML5 browser,

web runtime, web applications

and device API extensions.

“When combining Obigo’s

product breadth and experience

with the Green Hills Platform for

Digital Instruments, developers

are enabled to design the most

scalable vehicle HMI solutions

while delivering the highest per-

formance, security and reliabil-

ity,” said Dan Mender, vice presi-

dent of business development for

Green Hills Software.

Obigo has extended its web

offering to include automotive-

centric device APIs that facilitate

secure data sharing and control

of vehicle diagnostic, sensor data

and more over HTTP. The browser

and web runtime, when com-

bined with Integrity, deliver what

is claimed to be the industry’s

first automotive-grade secured

HTML5 web platform, providing

secured device API access. When

combined with Multivisor, the

platform can be used as an HMI

rendering engine that allows use

of the same HMI engine in a guest

os-agnostic manner.

“Obigo is pleased to be inte-

grated with Green Hills’ indus-

try-leading product offerings

currently in use by the demand-

ing automotive marketplace,”

said Obigo president David

Hwang. “We are excited to see

this partnership address the dif-

ficult challenges around design-

ing for maximum platform scal-

ability, security and reliability

while delivering next-genera-

tion, advanced HMI solutions to

the car.”

• Green Hills has announced

the availability of an Autosar

compatible API for the Integrity

rtos.

Keeping track around the worldMore than 50,000 people around the world logged on to monitor the progress of Mike Perham, the youngest person to circumnavigate the world alone by land. From July to October, the 20-year-old travelled more than 37,000km across 20 countries to raise money for disaster relief charity Shelterbox.

Leeds-based vehicle tracking company Remote Asset Management (Ram) provided the tracking kit for this feat, allowing thousands to log on and use real-time monitoring to keep up to date with Perham’s progress minute by minute.

During one moment on his trip, he was stuck in Alaska at -20˚C, at which point both his watch and mobile failed and his car battery froze solid. The vehicle tracking device remained working, ensuring family and friends knew he was still moving and safe.

“It has been an absolute pleasure to support Mike as he embarked on this world’s first,” said James Taylor (standing) from Ram. “Being part of something like this is brilliant and knowing we were playing an active part in not only Mike’s safety, but also the joy of others tracking his progress was fantastic.”

Green Hills and Obigo are working together on web applications for the car

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West Midlands, B90 8AS

www.vector-gb.co.uk

8 NEWS NEWS 9


Eris targets automotive for diodes expansionTAIWANESE COMPANY Eris

Technology has made its first

tentative steps into the automo-

tive market for its diode prod-

ucts following the company re-

ceiving ISO/TS16949 certifica-

tion last year.

Currently, only 1% of its out-

put goes into automotive but it

is targeting tier one companies

in south-east Asia for its prod-

ucts, which, according to execu-

tive vice president Vincent Chi-

ang, are a good fit for infotain-

ment systems.

“We are just at the beginning

for automotive,” said Chiang at

October’s Taitronics electron-

ics exhibition in Taipei. “We are

selling to a Korean company, but

we don’t exactly know what it is

being used in but probably a car

camera and video system.”

He said his company had not

set clear targets for how the au-

tomotive market would expand

during the next two years.

“You need to spend a very

long time to get accepted, so it

is hard to set targets,” he said.

“You can spend one to two years

just to get one part number ac-

cepted.”

He said expanding in Korea

would be the first step followed

by Taiwan and China.

“Then Japan will be a few

years later because it is so dif-

ficult,” he said.

Asked whether it was worth

the effort, he replied: “When

you get into automotive, it is

Audi and NXP form strategic partnership

of its latest-generation auto-

motive infotainment system to

Audi. The MMI Navigation Plus

platform is a fully integrated

infotainment unit to facilitate

high-quality playback of diverse

music and video files through

seamless connectivity via such

devices as IPod, hard disk drive,

smart phones and USB devices.

The system will premiere aboard

the 2013 Audi A3.

AUDI AND NXP Semiconductors

have signed a strategic partner-

ship focussing on automotive

electronics application segments

ranging from in-vehicle net-

working and car entertainment,

to emerging technologies for the

connected car. This includes car-

to-X communications, telemat-

ics, near field communications

and high-voltage controls for

electrical vehicles.

“The partnership is another

milestone in our progressive

semiconductor programme

(PSCP) and underscores the mu-

tual trust that both corporations

have built over many years,”

said Ricky Hudi, chief execu-

tive engineer for electrics and

electronics at Audi. “In addi-

tion, NXP’s strategy to provide

the electronic interfaces for the

connected car is smart and gives

clear indications for Audi’s fu-

ture plans.”

The PSCP is a semiconductor

strategy aimed at intensifying

the role of semiconductor com-

panies in the processes of the

German car manufacturer.

“It’s a real honour to serve as

a strategic innovation partner to

Audi in the premium car market,

and is a testament to the indus-

try recognising NXP’s excellent

customer support, commitment

to deliver top quality solutions

and above all our innovation

power,” said Kurt Sievers, gen-

eral manager for NXP’s auto-

motive business. “Our strong

collaboration with Audi rein-

forces that NXP’s focus on tech-

nologies for the connected car is

spot on with where the industry

is going.”

• Harman has started deliveries

Vincent Chiang: “You need to spend a very long time to get accepted.”

Ricky Hudi (left) and Kurt Sievers

Power battle

fo trucksENOCEAN IS

hoping its en-

ergy harvesting

technology will

win the day

over solar pow-

er for a wireless

warning sys-

tem being de-

veloped in the

UK for trucks. The system will

alert the driver of faulty bulbs

anywhere on the truck, but the

company developing the tech-

nology hasn’t decided which

technology to use to power the

system.

“As the truck bumps along,

you get vibrations to give

enough power to give a signal,”

said John Corbett, Enocean’s

sales director, at the recent Elec-

tronica exhibition in Munich.

“This is still in development and

they may go for solar power. It

may go one way or another.”

He said it would be about nine

months before the system would

be on the market and thus

couldn’t name the company car-

rying out the development.

He also said a company was

looking at the technology for

on-off switches in non-com-

mercial domestic vehicles.

John Corbett: “It may go one way or another.”

not easy to be displaced, so it

becomes very stable. Also, the

profit is much higher than in the

consumer market. A diode is a

very small part of a car so they

don’t mind spending a small

amount more for quality.”

Two of the company’s prod-

ucts launched at the show were

aimed specifically at the auto-

motive market. The DO-221AC

is for automotive and LED light-

ing while the TO-220SG is pri-

marily for power supply appli-

cations but can also be used in

automotive.

The firm was established in

1995 and has factories in Tai-

wan and Shanghai.

TT helps Mercedes develop kers for S ClassTHE MERCEDES S Class will be

one of the first vehicles to use a

derivative of the kers energy re-

covery technology used in For-

mula One cars. The German car

maker is working with TT Elec-

tronics to develop a version that

is viable for commercial cars.

“We need to make it lighter

and smaller, and we have to

condense it without using the

expensive technologies of a For-

mula One vehicle,” said David

Winter, TT’s vice president of

global sales, at the Electronica

exhibition in Munich. “We have

built up the knowledge to work

on this.”

He said the company had been

working on Formula One vehi-

cles and he said it could use that

experience of working in such a

quickly developing market.

“We worked on Formula One

and we have to look at how to

commercialise that product go-

ing forward,” he said. “We are

in discussions

with companies

about that.”

The company

is also launch-

ing a range of

resistors for

automotive ap-

plications to

offer protection

against surges

if the battery is disconnected.

“The challenges in the hybrid

vehicle market can be summed

up with the word ‘power’,” he

said. “We have resistors in these

vehicles and we are looking at

how we can put our power mod-

ules in there. This is about reli-

ability and high temperature op-

eration. You don’t want to have

to repair things. It is a challeng-

ing environment.”

He said it would probably

be about 18 months before the

company had power modules

ready for these applications.


Influx cuts data logger pricesINFLUX TECHNOLOGIES is

hoping that the price of its Rebel

LT data logger will make it pop-

ular with large fleets despite its

reduced functionality. The com-

pany is selling it at around the

£1000 mark, which it says is at

least 50% cheaper than many

high-end models. These include

products from the likes of Etas

and Vector.

But it has achieved this by re-

ducing the number of features

compared with its existing Rebel

XT product.

“The idea is that it will be more

affordable for those with large

fleets,” said Lance Keen, Influx

director, at the Advanced Engi-

neering show in Birmingham in

November. “These are tradition-

ally a lot more expensive.”

The reduced cost has been

achieved by lowering the IP

rating and making the product

less robust.

“There is also no on-de-

vice display,” said Keen. “It is

also slower than our high-end

model.”

But he said the two data log-

gers used the same software and

set-up techniques.

“But if you want more data

and higher speeds, then use the

high-end data logger,” he said.

Lance Keen with the Rebel LT

David Winter: “We have to look at how to commercialise that product.”

10 NEWS NEWS 11


Micrel continues attack on Most

McLaren lands Formula E contract

MICREL CONTINUED its attack

on the Most connectivity stand-

ard during the Electronica show

in Munich in November. The

company has recently joined

forces with Marvell to push Eth-

ernet as the best network for in-

car communications (AE, issue

three, 2012), but it knows first it

has to break the hold of Most.

“Most is an open stand-

ard with a single source,” said

Micrel’s senior product manager

Mike Jones at the show. “Price,

bandwidth and power savings

have not been delivered. With-

out competition, the rate of

change is slower.”

MCLAREN ELECTRONIC Sys-

tems is to provide the electric en-

gine, transmission and electron-

ics for cars that will participate in

the FIA’s new Formula E series.

McLaren will be a partner of

Spark Racing Technology, which

is led by Frédéric Vasseur and is

dedicated to the creation and as-

sembly of the electric cars par-

ticipating in Formula E.

McLaren and Spark will work

together to design and assemble

the electric cars, which will soon

be racing around cities across the

globe.

“I’m a passionate believer in

the role that motorsport can play

The company makes power

management and network-

ing products, which it says go

well together in the likes of IP

cameras. Key to this is its ripple

in showcasing and spearheading

the development of future tech-

nologies, and regard the Formu-

la E concept as an exciting in-

novation for global motorsport,”

said Martin Whitmarsh, CEO of

the McLaren Group. “McLaren

has worked with Frédéric Vas-

seur for many years, and our

association has been very suc-

cessful.”

The Formula E Championship

will be launched in 2014. It will

only use electric powered cars,

will run exclusively in major

international cities and has the

assets needed to reach a world-

wide audience. As well as being

blocker technology that can be

used to block noise.

“The sensor guys get excited

about our ripple blocker because

it reduces the noise,” said Jones.

“The main area is automotive;

that is a key market for us.”

He said that going forward

cars were going to be covered

with cameras, not just for rear

view but for detecting road

markings, signs, people, objects

and so on.

“When you start networking

these, Ethernet is the de facto

for networking,” he said. “You

need bandwidth. You don’t want

compression.”

an urban race series, it will fa-

cilitate the development of elec-

tric car technology that could

one day be used in mainstream

road cars.

“I am proud and happy to give

birth to this project that is inno-

vative and extremely rewarding

for a company both technically

and philosophically,” said Vas-

seur. “Personally, I can write a

new chapter, regardless of my

other ventures in motorsport.

Confidence and commitment

from our partner McLaren is a

guarantee of quality and relia-

bility without which this project

would not have been possible.”

MOUSER ELECTRONICS has

added four block diagrams to

its automotive applications web

site. These should help design

engineers find the latest auto-

motive advancements.

They can source product in-

formation via block diagram

navigation, and pinpoint the

technical resources. The site

also has some of the latest prod-

ucts from manufacturers such

as Texas Instruments, Murata,

Molex, ST Microelectronics and

Infineon.

The four application diagrams

cover braking systems (ABS),

electric power steering, central

body control and seat control.

This is in addition to its focus of

covering the instrument cluster,

rear vision systems, keyless en-

try, plus other industry news

and technical resources.

The block diagram naviga-

tion and streamlined graphical

interface is designed to speed

navigation. Combined with the

featured products section, en-

gineers can quickly steer them-

selves to products and informa-

tion based on defined param-

eters and engineering standards

– all centred on automotive-

specific design needs. Engineers

can review application notes,

white papers and videos, as well

as automotive-ready products.

To learn more, visit www.

mouser.com/automotive-appli-

cations.

Blocks aid

application

search

Mike Jones: “Without competition, the rate of change is slower.”

What the Formula E cars will look like

Central body control application block diagram

Toshiba plans security updateTOSHIBA ELECTRONICS has

designed a security module for

automotive microcontrollers,

which is said to meet standards

aimed at protecting vehicle elec-

tronics against hacking, tamper-

ing and software IP theft.

The TSM module was devel-

oped at the company’s Eldec

European automotive LSI devel-

opment centre n Düsseldorf, and

will be built into future genera-

tions of the company’s automo-

tive microcontrollers, with the

first expected to be sampling as

early as spring next year.

The module’s firmware is, as

a first release step, compliant

with the Secure Hardware Ex-

tension (She) version 1.1 speci-

fication of the Herstellerinitia-

tive Software (HIS), a technical

collaboration between five Ger-

man car manufacturers.

The hardware security module

has its own sub-CPU core that

manages a symmetric AES-128

cryptographic engine along

with other security elements.

As a result, it provides security

and tamper resistance without

consuming host microcontroller

CPU resources.

“Our TSM will help the auto-

motive industry prevent intellec-

tual property theft or manipula-

tion, which is a significant threat

as an increasing proportion of

innovations in new car models

are now software based,” said

Klaus Neuenhueskes of Toshiba

Electronics. “Moreover, the

strong security afforded by our

She-compliant TSM will protect

car owners against abuses such

as tampering with odometer set-

tings, or sub-standard servicing

by unqualified agents.”

The company plans to imple-

ment it in future variants of its

automotive microcontrollers

based on the Arm Cortex proces-

sor architecture, and will release

software libraries to support the

devices. Future updates compli-

ant with upcoming standards

(for example, in accordance with

Evita Medium requirements) in-

cluding TSM firmware updates

are planned.

The related software librar-

ies for the main microcontroller

CPU will enable developers to

design in accordance with the

latest version of the automotive

industry’s common software in-

frastructure promoting modu-

larity, scalability, transferability

and re-usability.


DIA

RY

DATES

will send an email alert to the

main system,” he said. “It will stay

there until it has been dealt with.

It can also be pushed direct to the

workshop.”

Penny Lyon, managing director

of Cumfybus, said: “The compre-

hensive workshop system manages

our scheduling and maintenance

compliance, and we have intro-

duced the driver’s walk around

check to manage the driver’s first

use inspection. As a management

team, we can instantly see the

checks as they are completed and

can rectify defects efficiently, sav-

ing downtime.”

AFTER SIX years of successful

operation on trucks, Magic In-

ternet Technologies is moving its

internet based fleet management

system over to the bus market.

And after trials with Cumfybus in

Merseyside and Airporter in Derry,

the company officially launched

the system – called Busfile – at the

Eurobus show in Birmingham in

November.

The previous Truckfile prod-

uct was introduced in 2006, has

11,000 users and has been installed

on around 110,000 commercial ve-

hicles.

“We have now moved into the

bus market,” said Paul Whitting-

ham, marketing manager. “We

have done one in Northern Ireland

and one in Liverpool and we are

talking with a lot more.”

The system lets fleet operators

scan in legal documents such as

MoTs and safety certificates and

produces a document timeline so

the user can see all relevant docu-

ments for a particular vehicle on a

particular date.

“The history is kept for the life of

the vehicle,” said Whittingham. “If

you have internal workshops, you

can set up workshop schedules

Fleet manager moves to buses

and email alerts.”

A compliance management fea-

ture can be used to prove all the

maintenance has been done at a

set time. An option is an electronic

check system for drivers.

“Some drivers just sit in their

cabins and tick boxes,” said Whit-

tingham. “This system means they

have to get up and walk round the

vehicle.”

The driver has to scan in QR

codes situated around the vehicle

and then answer on a handheld

device various safety questions re-

lated to that location.

“If the driver finds a defect, that

Paul Whittingham demonstrates how Busfile works

Consumer Electronics Show8th-11th January 2013Las Vegas, USAwww.cesweb.org

Autosport International10th-13th January 2013Birmingham, UKwww.autosportinternational.com

North American International Auto Show16th-27th January 2013Detroit, USAwww.naias.com

Automotive World16th-18th January 2013Tokyo, Japanwww.automotiveworld.jp

V2X for Auto Safety & Mobility20th-21st February 2013Frankfurt, Germanytelematicsupdate.com/v2xeurope

Advanced Battery Development26th-27th February 2013Aachen, Germanywww.battery-power.eu

Embedded World26th-28th February 2013Nuremberg, Germanywww.embedded-world.de

Geneva International Motor Show7th-17th March 2013Genevawww.salon-auto.ch

Commercial Vehicle Show9th-11th April 2013Birmingham, UKwww.cvshow.com

Autotronics10th-13th April 2013Taipei, Taiwanwww.taipeiampa.com.tw

Most Forum23 April 2013Stuttgart, Germanywww.mostforum.com

Global Automotive Components & Suppliers4th-6th June 2013Stuttgart, Germanywww.globalautomotivecomponentsand suppliersexpo.com

12


Steve Rogerson

reports from

November’s

Advanced

Automotive

Electronics

conference in

Daventry

AAE 2012 was held at

the Daventry Court Hotel

13


Market showing steady growth despite problems in EuropeDESPITE A somewhat gloomy

picture in Europe, the market

for automotive electronics is

continuing with an overall

steady growth, according to

Ian Riches, director of global

automotive practice at Strategy

Analytics.

“There has been quite

steady growth in automotive

electronics, and that will

continue,” he told delegates.

One of the key drivers,

however, is the number of cars

being produced, and here the

outlook has been worsening

over the past year, with the

situation in Europe particularly

bad. This is being countered by

the growth in the amount of

electronics per vehicle.

“But the content per car

average could be flattening

off,” he said. “This is because of

production transferring to India

and China where the content of

electronics tends to be lower.

This is dragging down the global

average.”

At the moment, he said,

the market for automotive

electronics was growing at about

10 to 20% per year worldwide.

to get into with huge investment

from a relatively small number

of players.”

Connectivity requirements are

growing with people wanting to

connect their smart phone with

the car, but navigation systems,

once a fast growth area, have

stalled.

“The days of £2000 navigation

systems have gone,” said Riches.

“People now either expect

navigation as a standard fit, or

use their phones, or buy a £100

Tomtom system.”

The news from the USA of

some states allowing a degree

of autonomous driving, albeit

always with a human in overall

control, has led to speculation

as to whether this will take off

in a big way.

“Fully autonomous vehicles

will take many years to mature,”

said Riches. “But humans are

becoming more willing to hand

over parts of the control to the

car. Cruise control has become

accepted and it will grow as more

autonomous features become

available. The first autonomous

system was parking and that is

becoming more sophisticated.

In Europe, this growth was only

5%, with the UK bucking the

trend slightly with a growth of

10%.

“Automotive electronics is

a growing market, but Europe

is a back water,” he said. “It

is the weakest region. But the

emerging markets are more

fragmented.”

As to car types, he the said the

fastest growth in electronics was

in the smaller vehicles. This was

particularly noticeable in India

where production of small cars

was increasing rapidly.

Other fast growth areas,

unsurprisingly, are hybrid

and electric vehicles, plus the

trend towards advanced driver

assistance systems (adas).

The problem with the HEV and

EV market though is the lack of a

large number of players. Toyota,

for example, is responsible for

70% of the market, and even

though that is shrinking as more

car makers take the plunge,

Riches predicted that even by

2019 it would still have 25%.

“There is very big market

potential in HEV and EV,” he

said, “but it is a tricky market

We are seeing more steps in

this direction but it won’t be an

overnight thing.”

The Euro NCap rating could

start to play a major role in

this, he said, as the indications

are that within a few years cars

will have to have some form

autonomous braking system

if they are to get the full five

stars.

These types of driver assist-

ance were one of the fastest

growth areas, he said, and

features such as cruise control

were moving from premium

brands into more cheaper cars.

Here, though, some are levelling

off the cost of making the car

by making structural savings.

“If a car never crashes,” said

Riches, “it can be made out of

paper. The structural aspects

become less important.”

However, conference chair

Elias Stipidis, director of the

vetronics research centre at

Brighton University, asked

whether extra safety systems

could have the opposite effect to

what was intended.

“These increase safety to a

certain extent,” he said. “But

Elias Stipidis: “These increase safety to a certain extent,”

Ian Riches: “If a car never crashes, it can be made out of paper.”

Philip Clarke: “Your brain still has to process a lot of information.”

Chris Hills: “Will you have to have different driving tests?”

Mark Fowkes: “We might have to see what accidents are caused before we can regulate.”

if these sensors bombard the

driver with all this information,

does the driver spend more time

looking at this information and

thus damage the safety?”

Philip Clarke, business

manager for DSpace, said it was

a matter of how this information

was presented to the driver.

“Is it giving the driver

raw data or making it more

intuitive?” he said. “The driver

is processing enough raw data

from looking out of the window.

It is possible to misinterpret a

complex image. It is a question

of how the ECU interprets the

information and presents it to

the driver.”

An alternative problem is that

if there is too much autonomous

control, the driver may lose

concentration because he or she

starts to think the car can handle

any situation. This is a problem

that airlines have already come

across.

“On long-distance airlines,

they are finding that the pilots

are going to sleep because all

the senor information is being

handled automatically,” said

Chris Hills, CTO of Phaedrus

Systems. “Could this happen with

car drivers? Will the driver start

fading out the information?”

Head-up displays are one way

to help in that the driver can

see the information from the

car while still being focussed

on the road.

“But your brain still has to

process a lot of information,”

said Clarke.

This raises the question of

how to design a system that

can suit all drivers with such

a vast difference in skills and

concentration levels.

“It is important to understand

the impact of new technology

on drivers,” said Mark Fowkes,

senior engineer at Mira. “People

have a range of driving skills

from the naïve to the more

experienced. If you allow the

driver to tune the system, is

it being done correctly? If

someone else is tuning it, how

do they know the driver?”

Hills also raised the question

of how these systems will affect

the driving test.

“Will you have to have

different driving tests?” he

said. “You have to have them

for geared and automatic cars.

Maybe there will be tests for

with and without a head-up

display.”

But Fowkes said it was hard to

regulate for these systems until

we knew how drivers would use

them.

“We might have to see what

accidents are caused before we

can regulate,” he said.

There is also the Volvo factor,

which happened in the 1980s

when the Volvo cars were so

solidly built that their drivers

believed they couldn’t be hurt

and some drove accordingly

giving the car the reputation of

being the worse driven car in

Britain.

“If people are aware they have

safety systems, they tend to

drive in a more reckless way,”

said Clarke.

Feeling the futureDelegates were treated to a rare chance of experiencing a rather unusual DeLorean car with this full-scale replica of the vehicle made famous in the iconic Back to the Future films. Built by a former Nasa electrical engineer who used to work at Universal Studios, the car is not only screen accurate but can also perform some of the special effects. And they can all be activated wirelessly along with audio clips from the film. Sadly, though, the time travel function was disabled and all the delegates were still in 2012 at the end of the show. The car was provided by Fusion Time Travel.

14


Controlling ECUs to save powerHAVING ALL the ECUs in a car

running at full power all the time

is wasteful and electric vehicles

will struggle to maintain that.

Even petrol engines are using

more fuel to handle the power

requirements and ways need to

be found to control the use of the

ECUs just to what is necessary.

For every 100W of energy

in a car, that uses an extra 0.1

litre of fuel per 100km, which

equates to 2.5g of CO2 per

kilogram, according to Alistair

Robertson, a systems engineer

with Freescale Semiconductor.

Passenger cars worldwide

account for about 5.5% of CO2

emissions and in Europe that

rises to 12%.

“Fuel costs are doubling every

ten years,” said Robertson. “Any

impact, however slight, on fuel

efficiency is welcome.”

He is looking at ways banks

of ECUs can be switched off

when not used to save power

as well as considering standard

techniques such as sleep and

standby modes.

“The goal is to spend as much

time as possible outside the full

run mode,” he said. “Another

technique is to only clock what

is required. Controlling the

clock is a major contributor to

the power. You can stop the

clock and only wake it up when

it needs to do something.”

Multi-core, which is becoming

more popular in automotive, he

said, also gave more performance

per milliwatt. He also encouraged

designers to find way of doing

things without using the CPU.

“The CPU is the most power

hungry module in the core,” he

said, “so if you can disable that

and let something less powerful

do the job then you can save a

lot.”

Another technique is to

use partial networking where

individual or groups of ECUs

can be started up and shut down

as needed, and this includes

the communications with

the ECUs. The alternative is

pretended networks where ECUs

are switched to a low power

mode while keeping up bus

connections.

“This is a local approach,”

said Robertson. “It doesn’t need

something else telling it to

shut down; it does it itself. You

Alistair Robertson: “The CPU is the most power hungry module in the core.”

15


Autosar falls short on diagnostic interface

ONE OF the problems with

Autosar is the diagnostic event

manager, basically an API that

forms the bridge between the

diagnostic software and the

interface seen by the engineers

and service personnel. However,

this interface is too much geared

towards software engineers,

according to David Price, chief

technical officer at Pi Innovo.

“The API is very much written

for software engineers,” he said,

“which means you need another

layer to translate for the systems

guys. This probably leads to errors

when you cross the boundary. The

fewer APIs the better as there is

less scope for confusion.”

He proposed a single API that

sat on the boundary between

the infrastructure and the

monitors. And he described the

infrastructure as like an iceberg

with the bulk of it unseen by

those who do diagnostic work.

“It is a complex area,” he said.

“There are over 3000 pages of

specifications that you have to

follow. But the service guys just

need to know what is wrong with

the car and how it can be fixed.”

While similar, the regulations

are slightly different for each

country. And the systems have to

handle the problems of different

vehicles.

“So, you can be more abstract

or more flexible with the API,”

said Price. “You have to decide

how much flexibility you want

or how much you want it to do

what the regulations say. You

have to be aware of the 3000

pages of regulations but have

enough flexibility to work round

the wrinkles depending on which

vehicle you are working with.”

He said the API choice therefore

depended on the target audience.

“What do the guys who are

designing the monitors want to

think about?” he asked. “They are

generally working with high-level

tools such as Simulink, so you

want the interface to work in the

language with Simulink blocks.”

The idea he said was to

configure it so the user sees the

simple stuff and the complex stuff

is underneath.

“It is the simple high-level

interface that is the important

thing,” he said. “You have to build

up all the blocks underneath that

manage the data. And then you

have to put it all together with all

the faults. There is a lot. There can

be 500 to 1000 faults. The target

audience are system engineers

and not software experts, so you

need to hide all the software.”

Can one DC-DC converter handle all the voltage levels?IF EUROPEAN Union CO

2 and

tailgate emission targets for

2020 are going to be met, then

electric and hybrid electric

vehicles will be necessary, but to

get the most out of these a more

efficient way must be found for

converting battery voltages into

other voltages needed round the

car.

Peter Tibbles, research mana-

ger for Prodrive, reported on

the work from two consortia

looking at producing an all-

in-one DC-DC converter that

can handle the temperature

difficulties encountered in

vehicles.

The EU has set targets for

both 2015 and 2020, but Tibbles

said the targets for 2015 could

be met by improving existing

technology.

“The industry is slightly

ahead of the curve with more

fuel efficient vehicles and more

diesels,” he said. “To hit the

2015 target, that will be done

by making existing technology

more efficient. But to get to the

2020 target, a lot more work

needs to be done, and that is

where they are looking to HEVs

and EVs. It is forcing the market

to do things differently, and one

way is to electrify part of the

drive train.”

If an electric vehicle has a

200 to 250V battery, a DC-DC

converter is needed to bring

that down to 12V for the legacy

systems in a car. But if another

DC-DC converter increases that

to 500 to 600V for the motor,

the current and the losses can be

reduced.

“You can have smaller battery

packs and use DC-DC conversion

to boost the voltage for the

motor,” he said. “This is the way

it has gone on the Prius range.”

He said though there was

no clear winner on finding a

technology that suits all drive

cycles for electric vehicles.

“There are a lot of technologies

being touted as the next big

thing for automotive,” he said.

Prodrive was part of a

consortium set up in 2010 to

look at DC-DC converters. Other

partners included Manchester

University, Raytheon and Tata.

The key part of the work they

are doing is using silicon carbide

(SiC) for the semiconductor

material.

“This has significant

advantages over silicon,” said

Tibbles. “It will operate at higher

voltages and temperatures.

It can switch at much higher

frequencies, and this means

you can reduce the size of the

capacitors and inductors. You

can also reduce the size of the

cooling pack and ultimately

delete the cooling pack.”

However, the main problem

with SiC is that it is relatively

new and hence more expensive

that silicon. The goal though

of the consortium is to reduce

the cost of the entire system

and have it in a much smaller

package.

Peter Tibbles: “Our goal is to have a single box.”

don’t need dedicated hardware

to support this. But the power

savings are not as great as with

partial networks.”

He said though there was a

limit to what could be done

within the microcontroller and

that system-wide techniques

had to be applied.

Another problem concerns

high temperature operation. SiC

can work at up to 500˚C but

the other parts in the package

need to do the same, including

the box in which it all sits. Thus

another consortium was set up

in July this year to look at all

the temperature issues. This will

run for two years and, as well

as Prodrive, its members include

TT Electronics, GE, Ricardo and

Warwick University.

“Our goal is to have a single

box that can handle multiple ins

and outs and work both ways,”

said Tibbles. “It will reduce

complexity. We also want

some sort of plug-and-play

capability.”

This means all the different

voltage levels in the vehicle

can be handled from a single

device. Because that becomes

a hub for the vehicle’s power

management requirements, there

is the potential to add other

functionalities using software.

The next stage of the project

will be looking at the safety

aspects and the effects of ISO

26262. That will start in the new

year.

Different approaches to consolidating ECUsTHE NUMBER of ECUs in a car is

increasing with each generation,

with some models having up to

150 units and some 1.5km of

cable connecting them.

One answer appears to be ECU

consolidation. But this must be

done in a way that maintains

safety and security – non-critical

systems must not interfere with

crucial functions.

Yet consolidation

must take place when

more electronics is

being called for in

cars, such as adaptive

cruise control and

other advanced driver

assistance systems

(adas), as well as

c o m m u n i c a t i o n s

with other vehicles

and information

infrastructures (V2V and V2I).

Two approaches were put, one

by Franz Walkembach, senior

project manager at Wind River,

and one by Rolland Dudemaine,

technical manager at Green Hills

Software.

“The car is becoming a node

to the cloud,” said Walkembach.

“There are lots of devices in the

car that are communicating with

each other.”

Dudemaine added: “One way

to reduce power is to reduce

the number of chips, and thus

the number of boards and the

amount of cable in the system.

You also want to reduce the

software complexity, but

software complexity is going up

not down.”

One of the first tasks

when considering

consolidation is to

look at how ECUs can

be grouped together

into areas such as

powertrain, chassis,

body, safety, adas,

and V2V and V2I

communications.

“The number of

ECUs is going down

in the older groups

but growing in areas

such as adas, V2V and V2I,” said

Walkembach. “And the number

of sensors in the car is growing

by about 50% per year. The

question is how to consolidate.”

The obvious answer is to

put more functionality on the

chips, which not only reduces

the number of chips but also

the communications needed.

However, Dudemaine warned

that this came with dangers.

“If a failure crashes the whole

system,” he said, “there is no

easy way to see where the failure

occurred. If you integrate more

functions, you have stability

problems.”

Walkembach said there were

three main options, the first

being letting the software run on

a main ECU with one operating

system. Alternatively, have

virtual management of devices

or virtual ECUs taking advantage

of multi-core technology.

Considering virtualisation,

there were three options: a

hypervisor or virtual machine

monitor; Linux containers;

or Linux kernel-based virtual

machines (KVMs).

“It all depends on the use,”

said Walkembach, “or how many

software partitions, graphics,

user interfaces and real-time

requirements that influence

what operating system to use.”

In the virtualisation and

partitioning approach, there

would be a single or multi-core

processor on top of which sits

the hypervisor and on top of

that the virtual machines each

with a guest operating system.

“Virtualisation lets you

partition a system and that gives

Franz Walkembach: “The question is how to consolidate.”

Rolland Dudemaine: “A separation kernel brings freedom from interference.”

you fast boot

options,” said

Walkembach.

“When one

p a r t i t i o n

crashes you

can define the

hype rv i so r

such that

other par–

titions don’t see it at all.”

Each partition can have the

data assigned in different ways,

from no trust to full trust,

and they can have definitions

specifying how the data are

transmitted.

Dubemaine believes the

answer to these problems is to

use a separation kernel.

“This means the amount of

code with access to all the systems

is the minimum possible,” he

said. “The application code has

no way to access memory from

outside its own application.”

He said the operating system

could guarantee there were no

unintended communications

as the user could define all the

paths that were allowed.

“A separation kernel brings

freedom from interference when

integrating multiple ECUs on

one chip,” he said.

David Price: “You need to hide all the software.”

16


How to keep Formula One cars on trackTHE PROBLEMS of keeping

the electronics working on

a Formula One car can be

nightmarish but it could all

become even worse as new

control units and powertrains

are brought in for all teams over

the next two years.

Peter van Manen, managing

director of McLaren Electronic

Systems, explained to delegates

in his keynote speech how, with

so little testing, the development

of a Formula One car continues

throughout the racing season.

“There are three to eight large

engineering upgrades in the two

weeks between races,” he said.

“Teams are making thousands

of components each year. And it

is a very violent environment in

which they have to operate.”

And with in-season testing

banned these upgrades are only

really put to the test on the

each car sending about 1.5Gbyte

per race. The people at the team’s

headquarters are also receiving

the same real-time data so they

can provide inputs as well.

“In the one hundred minutes

of a race, everything has to be

reliable,” he said, raising a few

smiles given McLaren’s problems

this season.

McLaren provides the

electronic control unit for all the

cars, and van Manen explained

the difficulties in keeping it cool.

Though it might seem logical to

use the airflow from the fast

moving vehicle to provide the

cooling, this is a bad idea as it

can compromise the finely tuned

aerodynamics.

The team’s current challenge

though is building the new

control unit for the 2013 season

ready for the new powertrains

due to be introduced in 2014.

Delegates browse the exhibits at the Advance Automotive Electronics show

“It is quite an exciting stage,”

he said.

One big difference will be that

the processor will be partitioned

in a way that will allow all the

teams to write some of their own

software.

“We will create a single version

of the software that everyone

uses but there will be elements

that the teams can use,” he said.

“It will be standard electronics

with the flexibility the engineers

will need when they build the

new powertrains.”

race weekend, which is why

telemetry plays such a crucial

role in grand prix racing. A

race car, for example, will have

around 120 sensors.

“These are very highly strung

machines,” said van Manen,

“so we monitor the health to

see very quickly if something

goes wrong. Also, with no

testing during the season, it is

important to monitor the cars to

get the optimal set-up.”

He said that teams build the

car, spend the season trying to

make it better and then throw it

away and start again.

“So we need to understand

what we have very quickly,” he

said.

During a race, he said, up

to 500 parameters were being

logged at about 1kHz. Around

2.4Mbit/s of data are being sent

from the car to the garage, with

Peter van Manen: “Teams are making thousands of components each year.”

18 POWER TECHNOLOGIES


Lithium-ion batteries require

considerable care if they are

expected to operate reliably

over a long period. They cannot

be operated to the extreme end of

their state-of-charge (SoC). The

capacity of Li-ion cells diminish and

diverge over time and usage, so every

cell in a system must be managed to

keep it within a constrained SoC.

To provide sufficient power for a

vehicle, tens or hundreds of battery

cells are required. These cells must

be configured in a long series;

as much as 1kV and higher. The

battery electronics must operate in

this very high-voltage environment

and reject common mode voltage

effects, while differentially measuring

and controlling each cell in these

strings. The electronics must be able

to translate information from the

battery stack to a central point for

processing.

On top of these requirements,

operating a high-voltage battery

stack in a vehicle or other high-

power applications imposes tough

conditions, such as operation with

significant electrical noise and wide

operating temperatures. The battery

management electronics are expected

to increase operating range, lifetime,

safety and reliability, while reducing

cost, size and weight.

Battery managementThe electronic system that measures

and manages the battery stack

(also known as the BMS, or battery

management system) has three key

requirements.

First, the BMS must know the

health of each battery cell in the

stack. Primarily, this is accomplished

by estimating the SoC of each cell

in the battery system. The current

SoC can be combined with historical

information for determining the

status of each cell.

Secondly, the BMS must control

the SoC for each cell in a system.

This is done by controlling the

charge, discharge and balancing of

each cell in a system.

The third requirement concerns

safety. The BMS must know the

electronics are properly working

such that the battery information

is valid. The golden rule is that no

over voltage cell can appear as an

OK voltage cell. To do this, the BMS

has to communicate the status of all

cells and the BMS electronics to the

rest of the system.

The key element in the battery

management electronics is the

battery monitor IC. The battery

monitor performs the difficult task

of accurately measuring the voltage,

current and temperature of each cell

and passing the data to a control

POWER TECHNOLOGIES 19


circuit. A controller then uses the

cell data to compute the state of

charge and state of health of the

pack. The controller may command

the battery monitor to charge or

discharge certain cells to maintain a

balanced state of charge within the

pack.

Battery monitorLinear Technology has completely

redesigned its high-voltage battery

monitor chip in a move that it

claims will raise the bar for stacked

battery monitoring in hybrid and

electric vehicles. The LTC6804 chip

has had all aspects of the design

changed from its predecessors – the

LTC6802 and LTC6803.

“This is the state of the art in

terms of a stacked battery monitor,”

said Erik Soule, vice president

and general manager of signal

conditioning products. “This comes

from a lot of different things all

working together. We have dealt

with every issue we have been asked

to improve.”

The chip will monitor a bank of

12 cells at voltages up to 4.2V with

16bit resolution and better than

0.04% accuracy. This is claimed to

be four times more accurate than the

predecessors.

A key upgrade is the use of two

16bit ADCs rather than one 12bit

circuit in the LTC6803.

“This means it will run at ten

times the speed,” said Soule. “And

it lets us better synchronise voltage

and current measurements. You

get closer time alignment between

voltage and current and that

is important for calculating an

accurate state of charge.”

One difficulty the company had

designing the chip was trying to

make it work with a standard SPI

interface. In the end, the designers

opted for the proprietary IsoSPI

interface, which means the device

has to be used with the companion

LTC6820 chip to translate signals to

and from this environment.

“We tried to find a standard

bus but failed,” said Soule, “so we

designed our own IsoSPI. This is

new.”

The voltage reference technology

is completely different from the

older chips to improve measurement

accuracy and long-term stability.

And there are more built-in self test

circuits than the predecessors.

Also important is that it has been

engineered with ISO26262 in mind.

“There are features to help the

system designer comply with the

specification,” said Soule.

The use of burned Zener

technology is said to improve time

and temperature stability giving it

references similar to that used in

precision instruments.

“Nobody else is using this or even

thinking of using it,” said Soule.

The company also plans to

introduce the LTC3300 bidirectional

active balancing device early next

year, and this will be controllable

by the LTC6804, which itself will be

in full production during the first

quarter of 2013.

“We have been sampling it with

out customers and had tremendous

interest,” said Soule. “The feedback

has been unbelievable. We are going

to change the industry with this. It

is a whole bunch of little tricks all

working together.” l

Erik Soule: “We are going to change the industry with this.”

Steve Rogerson reports on Linear Technology’s claims

to have raised the bar for battery monitoring

BalancingactLTC6804 battery monitoring devices

automotive electronics issue-4 - baixardoc

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