Automotive Electronics Issue-4 - BAIXARDOC
Transcript of 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
Published by: MT Publications Limited, Prudence Place, Proctor Way, Luton, Bedfordshire LU2 9PE, United Kingdom
Tel: +44 (0)1582 722460 Fax: +44 (0)1582 722470
Email: [email protected]
Web: www.automotive-electronics.co.uk
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
Victoria Wren, [email protected]
Advertisement Manager
David Williams, [email protected]
Circulation & Subscription Manager
Wendy Magee, [email protected]
Accounts & Administration Manager
Kim Hughes, [email protected]
Publishing Assistant
Ruthanne Hornshaw, [email protected]
Publisher
David Williams, [email protected]
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.
www.automotive-electronics.co.uk issue four 2012 | automotive electronics
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
automotive electronics | issue four 2012 www.automotive-electronics.co.uk
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
Test your Avionics Network
Efficiently and ReliablyWith focused support, development processes in electronic net-
working can be implemented in a more time-saving and cost-
effective way:
> Use protocol-specific tools to systematically and reliably
develop your network design.
> Find and avoid errors early in development conveniently
and cost-effectively.
> Validate changes made to the software and the communi-
cation system – quickly and easily – with regression tests.
> Exchange data with colleagues and development partners –
easily, securely and without overhead – whether from
databases, models or test scripts.
> Benefit from a multi-bus tool approach to developing,
testing and implementing gateways.
Improve the efficiency of your overall development process –
from design to testing and analysis – with the practice-proven
tools CANoe and CANalyzer and our comprehensive services.
More information and a demo version of CANoe with
AFDX® / ARINC 664 support: www.avionics-networking.com
Supported bus systems
and protocols:
AFDX® , CAN, IP, Ethernet,
ARINC 429 / 812 / 825 / 826,
CANaerospace, CANopen
AFDX® is an Airbus‘ registered trademark
Vector GB Limited
Solihull, Birmingham
West Midlands, B90 8AS
www.vector-gb.co.uk
8 NEWS NEWS 9
automotive electronics | issue four 2012 www.automotive-electronics.co.uk
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.
www.automotive-electronics.co.uk issue four 2012 | automotive electronics
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
automotive electronics | issue four 2012 www.automotive-electronics.co.uk
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.
www.automotive-electronics.co.uk issue four 2012 | automotive electronics
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
automotive electronics | issue four 2012 www.automotive-electronics.co.uk
Steve Rogerson
reports from
November’s
Advanced
Automotive
Electronics
conference in
Daventry
AAE 2012 was held at
the Daventry Court Hotel
13
www.automotive-electronics.co.uk issue four 2012 | automotive electronics
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
automotive electronics | issue four 2012 www.automotive-electronics.co.uk
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
www.automotive-electronics.co.uk issue four 2012 | automotive electronics
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
automotive electronics | issue four 2012 www.automotive-electronics.co.uk
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
automotive electronics | issue four 2012 www.automotive-electronics.co.uk
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
www.automotive-electronics.co.uk issue four 2012 | automotive electronics
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