FUTURE TECHNOLOGY MAGAZINE - FTM Board Club · FUTURE TECHNOLOGY MAGAZINE ISSUE 1209 In association with Design Note: page 13 ... GPS receiver, the Open AT application f ram ewok,

F U T U R E T E C H N O L O G Y M A G A Z I N E

I S S U E 1 2 0 9

In association with www.my-boardclub.com

Design Note: page 13Isolation amplifiers toughen up for the electric-vehicle age

Technical View: pages 26-27 MEMS sensors take navigation beyondGPS limits

Application Spotlight: pages 14-24Automotive-qualifed MOSFETs, sensors, MCUs and more

Component Focus: pages 2-12 QorIQ® P5 quad-core processors plusAirPrime® GPS & wireless modules

Apply for a dev board frommy-boardclub.com and youcould win an Apple® iPad®

Celebrating our 100th issue!We have 100 Freescale‘Freedom’ development boardsto give away – see page 25

AVX unveils high-performanceminiature wideband couplerAVX has developed a miniature wideband directionalcoupler with high directivity, targeting applicationsin GPS, vehicle-location systems, wireless LANsand matching networks, as well as mobilecommunications and satellite TV receivers. Thenew 0402 chip-size devices are built using thin-filmmultilayer technology, which results in excellentfrequency performance and rugged constructionfor reliable automatic assembly. Performanceparameters include directivity of 20dB, couplingfactor of 24dB ±2dB over the frequency range700MHz to 2700MHz, and a power rating of 3W.

Philips Lumileds introduces industry’ssmallest Power LEDPhilips Lumileds has introduced its smallest LEDpackage to date, measuring 2.2mm2 and capableof producing high lumen output across a fullspectrum of colours from 440nm to 670nm,including white. The new LUXEON® Z devices freedesigners from the constraints of typical 2mm x2mm multi-chip packages, and give the flexibility tocreate mono-colour or multi-colour luminaires invirtually limitless configurations. As many as 250 ofthe high-lumen LUXEON Z devices can bemounted within one square inch, allowing newlevels in lumen density.

ON Semiconductor introducesFlexRay™ 3.0.1-compliant transceiverON Semiconductor has added a bus-transceiverIC meeting the latest FlexRay Electrical PhysicalLayer Specification Rev. 3.0.1 to its portfolio ofautomotive networking products. The newNCV7381 is a robust, single-channel devicesupporting communications up to 10Mbit/sbetween the wired FlexRay communicationmedium and the protocol controller/host.

The new device has mode-control functionalityoptimised for nodes permanently connected to carbatteries. The device offers low-power operationand a low-power mode receiver that allowsremote wake-up detection. Capable of runningfrom a battery supply between 5.5V and 50V, theNCV7381 can be integrated into 12V or 24Vautomotive power systems.

IR reveals next-generation SupIRBuck®

regulatorsInternational Rectifier’s third generation ofintegrated SupIRBuck synchronous buck voltageregulators feature a newly patented modulatorscheme that generates the industry’s smallestjitter-free pulse widths. By dramatically reducingjitter for pulse widths as small as 50ns, thesedevices enhance closed-loop bandwidth resultingin excellent transient response and lower outputcapacitance. The ability to generate narrow pulses,coupled with robust source/sync-current capability,makes this family ideal for generating DDR-memorytermination voltage directly from a 12V input.

The new devices are the 12A IR3894 and 16AIR3895 in the 5mm x 6mm PQFN package, andthe 4A IR3897, 6A IR3898 and 9A IR3899 in the4mm x 5mm PQFN.

S T A R P R O D U C T

2 E M A I L I N F O @ M Y - F T M . C O M F O R S A M P L E S A N D D A T A S H E E T S

The architecture combines a wireless module,a GPS module based on a CRS SiRFstarIVGPS receiver, the Open AT applicationframework, which includes an operating system, a setof software libraries and anintegrated developmentenvironment based on theEclipse™ platform. TheOpen AT applicationframework allowsdevelopers to createapplications in standardANSI C/C++, and has beenproven in several milliondeployments worldwideover more than a decade.

Using the two modules with an external hostprocessor enables developers to configure asolution quickly without significant codedevelopment. The code runs on the hostprocessor, as usual, and executes ATcommands familiar to designers who haveworked with GSM.

Using the modules without a host processorenables designers to reduce Bill-Of-Materials(BOM) costs and achieve even fasterperformance. Code is loaded directly into themodule, and software elements can be addedto the design without increasing the overall cost.

A number of automotive-grade wirelessmodules are available, supporting 2G, 3G and4G connectivity options.

The GPS functionality is provided by theAirPrime XM0110 GPS module, which isoptimised for use with AirPrime wirelessmodules. The only external componentrequired is an active or passive GPS antenna.The GPS module offers high sensitivity ratingsfor tracking, navigation and acquisition. Itconnects directly to the wireless module'sUART serial interface or I2C bus, and canshare its power supply. Several low-poweroptions allow designers to optimise GPSperformance and system power consumption.

The module isalso able toremove white noise, todefend against frequency-jamming devicesused by thieves and hijackers and alsoimprove reception in noisy environments.

An off-the-shelf software library supports theGPS module and has dedicated APIs for a fullrange of GPS functions. Beyond the basicoperations for obtaining location data, themodule supports Assisted-GPS (A-GPS)functions that provide several additionalbenefits, including a faster Time-To-First-Fix(TTFF), better fixes in poor GPS-signalconditions, and increased position accuracy.

Designers can start work quickly and easilyby downloading a free copy of DeveloperStudio, which provides a complete set ofdevelopment tools including the Eclipse-basedIDE. Developer Studio allows coding,debugging, compiling, downloading, tracingand monitoring within a single environment.Sample applications and a range of readilyavailable building blocks are also provided.

SIERRA WIRELESS

APPLICATIONS• Telematics units for:

• Incident and emergency alert• Roadside assistance• Security tracking systems• Driving data and diagnostics

information• Usage-based insurance• Fleet management

FEATURES• AirPrime wireless module• Integrated wireless-antenna protection

and diagnostics• 10mm x 12.5mm x 2.5mm AirPrime

GPS module• Open AT application framework• ISO TS-16949 production• Cloud-based management services

ENERGY MEDICAL LIGHTING INDUSTRY SECURITY AUTOMOTIVE

my-ftm.com/120902FOR PARTS ANDLATEST PRICING


©Copyright 2012 Future Electronics Ltd. All trademarks contained herein arethe property of their respective owners. Applications for product samples,badge boards, demonstration boards, Future-Blox Boards and otheradvertised materials from Future Electronics are subject to qualification.

Newsin brief

Sierra Wireless AirPrime™ modulesenable automotive applicationdevelopers to build low-cost aftermarketGSM/GPS tracking boxes that delivera high level of functionality in a smallfootprint, and allow the flexibility todesign with or without a host processorto optimise both price and performance.

The AirPrime architecture permits design with or without a separate processor

GPS and wireless modules simplifytelematics development

C O M P O N E N T F O C U S

3V I S I T T H E O N L I N E F T M M A G A Z I N E A T: W W W . M Y - F T M . C O M

100V linear LED driver de-clutters low-powerlighting designs

The AL5801 delivers the combined benefits of a low component count, enhanced reliability andhigh energy efficiency

The AL5801 100V linear LED driverfrom Diodes Incorporated is capable ofdriving chains of up to 30 low-power,series-connected LEDs with currentsfrom 20mA to 350mA, and requiresonly one bias resistor and one current-sense resistor tocomplete a simplified,small-footprint solution.

The AL5801’s open-drainoutput operates between 1.1Vand 100V, ensuring common12V, 24V or 48V power railsare supported. By generatinga 0.56V reference voltageacross the LED-currentsensing resistor, which has alow ohmic value, the driver’sinternal control transistor helpsto minimise power losses andensure sufficient supply-voltage margin.

Due to the reference voltage’s negativetemperature coefficient, the output current isautomatically reduced at higher temperatures.This helps to protect the LED chain from anydamage, thus improving overall circuitreliability. In addition, the AL5801’s widejunction-temperature range of -40°C to 150°Callows the IC to be mounted immediatelyadjacent to LEDs in applications where PCBspace is limited.

APPLICATIONS• Automotive interior lighting• LED signage• Offline LED luminaires• Emergency lighting

FEATURES• Output-voltage range: 1.1V to 100V• Compensation pin for optimising transient

stability• External pin for PWM dimming control• Low thermal-impedance SOT26 package



DIODES INCORPORATED

PWM controller integrates comprehensive protectionsaving size, cost and component count

High feature integration in Fairchild's FSL206MRx PWM controllersmeets demands of cost-sensitive applications

Fairchild Semiconductor’s FSL206MRxhighly integrated PWM controllers areFPS™ Green-Mode power switchesthat help designers to minimiseexternal components when designinghigh-performance offline Switched-Mode Power Supplies (SMPS).

The FSL206MR and FSL206MRBN integratean avalanche-rugged SenseFET as well as aninternal regulator, which eliminates the need foran auxiliary bias winding. In addition, integratedhigh-voltage startup and soft-start circuitryprevents transformer saturation, while built-inprotection circuitry saves board space andreduces BOM costs.

The internal high-voltage startup switch andburst-mode operation, with very low operatingcurrent, reduce power losses in standbymode. This enables engineers to achievepower loss of 150mW with no bias winding,or to reduce loss to 25mW for FSL206MR or30mW for FSL206MRBN with bias winding atno-load condition.

Protection (LUVP) is also built in.Engineers can complete designs without

building a hardware prototype, using Fairchild’sPower Supply Web Designer. The online toolprovides a convenient ‘Auto-Complete’ optionthat requires only input and output parametersto be entered, while also giving the flexibility tofine-tune parameters individually for optimumperformance.

APPLICATIONS• Switched-mode power supplies for:

• Flat-panel televisions• Industrial equipment• Commercial appliances• White goods

FEATURES• 67kHz fixed operating frequency• Frequency modulation for EMI attenuation• 300µA operating current• Separated high- and low-voltage pins



FAIRCHILD SEMICONDUCTOR

For applications requiring simple LED dimming,the driver supports PWM output-currentregulation, achieved by driving its bias pin witha PWM signal via an external open-collectorNPN transistor or open-drain N-channelMOSFET.

Integrated protection features include Under-Voltage Lockout (UVLO), Leading-Edge Blanking(LEB), an optimised gate turn-on/turn-off driver,EMI attenuation, Thermal Shutdown (TSD)protection, and temperature-compensatedprecision current sources for loopcompensation. Fault-protection circuitry suchas Overload Protection (OLP), Over-VoltageProtection (OVP), Abnormal Over-CurrentProtection (AOCP) and Line Under-Voltage



APPLICATIONS• eCompass in mobile devices• Gaming and sports equipment• Patient monitoring and rehabilitation• Navigation systems• Mechatronic compensation• Usage logging

FEATURES• Supply-voltage range: 1.95V to 3.6V• Interface supply-voltage range:

1.62V to 3.6V• Low noise:

• Maximum 150µg/√Hz acceleration• Maximum 1µTRMS magnetic

• Autonomous hard-iron calibration• Integrated sensor self-test functions



FREESCALE enable an eCompass solution built using thissensor to achieve a typical orientationresolution of 0.1° and better than 5° compass-heading accuracy for most applications. Theacceleration full-scale measurement is

dynamically selectable between±2g, ±4g or ±8g. The

magnetic-measurementrange is fixed at

±1200µT. TheOutput Data Rate

(ODR) is userselectable andcan be setbetween1.563Hz and800Hz foreach sensor.

There is also ahybrid mode, with both

sensors active, which providesinterleaved magnetic and acceleration data atan ODR of up to 400Hz.

The FXOS8700CQ is available in a 3mm x3mm x 1.2mm plastic QFN package, which isfootprint compatible with the Freescale XtrinsicMMA8451, MMA8452 and MMA8453.

The Freescale FXOS8700CQ is a small,low-power 6-axis motion sensorcombining a linear accelerometerand magnetometer in asingle package,featuring embeddedprogrammable smartfunctions includingdetection of freefall,transient and single ordouble pulse/tap events, aswell as portrait/landscapeorientation detection andmagnetic min/max detection.

The device features a selectable digital I2C orSerial Peripheral Interface (SPI), and 14-bitresolution for accelerometer measurementsand 16-bit magnetometer resolution. Thecombination of high measurement resolutionand the integrated high-performance ASIC

C O R N E RANALOGUE

Rugged RF power amplifiers enable smaller,tougher land-mobile radios

This is significantly higher than most competingalternatives, which commonly range in efficiencyfrom 25% to 40%.

Designers can take advantage of theenhanced performance of these poweramplifiers to optimise system reliability forlower maintenance costs, use fewer amplifierstages to achieve the desired power gain,enhance stability, simplify cooling, and createsmaller, lighter radios.

APPLICATIONS• Personal mobile radios• Emergency-services radios

FEATURES• High gain• 12.5V DC supply voltage• Integrated ESD protection



FREESCALE

The AFT05MS031N and AFT09MS031NLDMOS power amplifiers,part of Freescale’s Airfast™

portfolio of RF powerproducts, deliver theindustry’s highestlevels of ruggedness,stability and gain forland-mobile applications.

Built to withstand harsh machine-to-machine communications environments, theAirfast products can survive a VoltageStanding-Wave Ratio (VSWR) greater than65:1 even with simultaneous over-voltage andover-drive stresses on the amplifier and its RFpower transistors.

The devices integrate much of the circuitryrequired to maintain stability, therebysimplifying design and supporting stabilityunder a wide range of operating conditions.Engineered for operation at frequencies

between 136MHz and941MHz, theAFT05MS031N andAFT09MS031Nremain stable whiledelivering rated

performance over thebreadth of their

operating-frequencyranges. Stability testing is

conducted using multiplevoltages, drive levels and

temperatures into a VSWRof 3:1.Freescale’s Airfast devices

also deliver the advantage of highoperating efficiency, typically around 65%.

Part Number Frequency Range Output Power Package Type

AFT05MS031N 136MHz-520MHz31W TO-270 2-lead overmolded; surface-mount

package optionAFT09MS031N 764MHz-941MHz

6-axis motion sensor embeds smart event-detection capabilities



By using proprietary technology tocombine a signal-processing IC with a16-bit ADC, infrared emitter, PIN diodeand ambient-light detector in theindustry’s thinnest package, the VishayVCNL4020 proximity and opticalsensor saves power and simplifieswindow placement in consumer andindustrial devices.

The VCNL4020’s interrupt function enables thesensor to work independently, only waking thehost microcontroller when a predefinedproximity or ambient-light event occurs. Thishelps to simplify software design and reducepower consumption by saving the microcontrollerfrom polling the sensor.

Housed in a rectangular leadless packagemeasuring 4.8mm x 2.3mm x 0.8mm, theVCNL4020 has a compact footprint and is thethinnest device of its type in the industry.

The infrared emitter and PIN diode combineto allow proximity sensing capable of operatingat depths or air gaps of up to 10mm. The

VISHAY

C O R N E RANALOGUE

The robust DF60 series connectors provide up to four high-currentcontacts on a 10.16mm pitch

Hirose DF60 series connectors arerated for currents up to 40A and areoptimised for high-power wire-to-board connections requiring robustand reliable connectivity within aspace-saving outline.

The overall dimensions of the DF60 connectorshave been designed to satisfy space-constrainedapplications. The plug and the receptaclehousing are low-profile units having a matedheight of only 30mm. The footprint dimensionsare minimised by the small pitch size of10.16mm. Right-angle and in-line versions areunder development.

The robust lock provides a positive tactilesensation and an audible click when mated.This confirms the connector is fully engaged,providing the assurance of complete electricaland mechanical connection. The lock ispositioned on the centre of the housing toavoid uneven locking and cable entanglement,thereby providing greater security than side-mounted locks. The centre location also allowsmultiple connectors to be mounted closertogether, side by side.

The plug utilises crimp contacts that have aunique internal structure with five contactpoints. Two of the contact points are fixed inthe upper section. The other three contactpoints are in the lower section and havesprung bases, which allow movement to follow

the flat structure of the male contact duringthe mating operation. This provides highcontact reliability, secure connection andstrong resistance against vibration. Keyingvariations are available to prevent mis-insertionof multiple connectors.HIROSE

APPLICATIONS• Robotic systems• Automotive interconnects• Medical equipment• Computer servers• Servo amplifiers• Motor drives

FEATURES• Number of contacts: 1 to 4• Cable-thickness range: AWG 8-12• UL and TÜV approvals• 30 mating-cycles lifetime• 3.0mm effective mating length



P.I.E.S E C T I O N

Ultra-thin proximity and ambient-light sensorsaves power, simplifies placement

APPLICATIONS• Touchscreen locking and adaptive

brightness control in:• GPS units• Digital cameras• White goods• Handheld computers• Industrial devices and displays• Wake-up function for any kind of

display

FEATURES• IC supply-voltage range: 2.5V to 3.6V• Infrared-emitter supply-voltage range:

2.5V to 5V• 1.5µA standby current consumption• Operating-current range: 5µA to 5mA• Proximity sensing:

• up to 20cm with internal emitter• up to 1 metre with external emitters



LED-drive current can be programmed in10mA steps from 10mA to 200mA to permitobject detection at a range of up to 200mm.With effective resolution of 16 bits, theproximity function benefits from high crosstalkimmunity, while signal modulation suppresseslight from other sources to ensure reliable andrepeatable detection. The VCNL4020 is alsoable to drive external emitters for longer range.

The ambient-light detection function,typically used for dimming of display or keypadbacklighting, has sensitivity close to that of thehuman eye. With dynamic range of 16 bits, thedetector maintains accurate response underlight-intensity levels from 0.25 lux to 16,000 lux.

40A connectors combinesmall size, secure mating andreliable multi-point contacts

Family of low-capacitance TVS diodes protectsEthernet ports and more


The SPA family provides required protection for multi-gigabit interfaces

The Littelfuse SPA™ family of Transient-Voltage Suppression (TVS) diodearrays has more than 10 types suitablefor providing mandatory protectionagainst induced surge events and ESDfor Ethernet ports.


The SP3002, SP4061 and SP4062 eachprovides four channels of low-capacitancediodes with an additional zener diode forprotecting sensitive I/O pins, and providesprotection exceeding the requirements ofinternational IEC standards. They can safelyabsorb up to 20A in accordance withIEC61000-4-5 (tP = 8/20µs) withoutperformance degradation, and provide ESDprotection per IEC61000-4-2. All three seriesare also able to provide up to 40A ElectricalFast Transient (EFT) protection, per IEC61000-4-4.

The SP3002 has rail-to-rail diodes with ultra-low capacitance of 0.85pF, making themsuitable for protecting ultra high-speed

interfaces including HDMI®. The SP3002 seriesprovides ±15kV air-discharge ESD protectionmeeting IEC61000-4-2, and devices arehoused in a choice of SC70-6, SOT23-6 or1.6mm x 1.6mm µDFN-6 package.

The SP4061 and SP4062, in the 2.6mm x2.6mm µDFN-10 package, integrate fourchannels of 3.5pF (line-to-ground) diodes, andare suitable for use with 10/100/1000 Ethernetports as well as telecom equipment and set-top boxes. Both series provide ±30kVcontact/air-discharge ESD protection meetingIEC61000-4-2. The SP4061 has a reverse-standoff voltage of 2.5V, while the SP4062 hasreverse-standoff voltage of 3.3V.

APPLICATIONS• Computer peripherals• Network hardware• Test equipment• Medical equipment• VoIP boxes• Set-top boxes• PBX systems• Home multimedia equipment

FEATURES• Low leakage current• Discharge protection

• ±12kV contact (SP3002)• ±30kV contact/air (SP4061/2)

• Snap-back voltage:• 2.0V (SP4061)• 2.8V (SP4062)



LITTELFUSE

High-current MOSFETs minimise conduction and switchinglosses for energy-conscious applications

Fairchild Semiconductor FDMS015N04B,FDP020N06B, FDP027N08B andFDMS039N08B N-channel MOSFETsutilise Fairchild’s advancedPowerTrench® process, which is tailoredto combine very low on-stateresistance with superior switchingperformance, for use in power supplieswhere high energy efficiency is aprimary target.

The four devices have maximum on-stateresistance of 1.5mΩ, 2.0mΩ, 2.7mΩ and3.9mΩ respectively, at a gate-to-sourcevoltage of 10V and specified drain current.

and FDMS039N08B, in the Power 56 package,benefit from an exposed drain pad and internalpackage construction that helps to minimiseon-state resistance in combination with theadvanced PowerTrench silicon technology.Together these features enable a strong on-resistance times gate-charge Figure of Merit(FOM), enhancing overall efficiency.


APPLICATIONS• Server power supplies• Telecom power supplies• Uninterruptible power supplies• Solar micro-inverters• Battery chargers• Battery-protection circuits

FEATURES• 100% UIL tested• Fast switching speed• Avalanche-energy rated• Operating-temperature range:

-55°C to 150°C



Part Number BreakdownVoltage

Rated DrainCurrent

GateCharge

Gate-drainCharge

Reverse-recoveryCharge

Single-pulseAvalanche Energy Package

FDMS015N04B 40V 100A 91nC 16nC 90nC 526mJ Power 56FDP020N06B 60V 313A 206nC 34nC 194nC 1859mJ TO-220FDP027N08B 80V 223A 137nC 28nC 112nC 917mJ TO-220FDMS039N08B 80V 100A 77nC 16nC 80nC 240mJ Power 56

Switching performance is enhanced due tolow reverse-recovery charge and the softreverse-recovery characteristic of theMOSFET’s body diode. The FDMS015N04B



Rugged triacs deliver high voltage, currentand temperature capability

APPLICATIONS• White goods• AC power tools• Lighting• Industrial applications• Safety and protection circuits• High-voltage ignition circuits

FEATURES• High noise immunity• High immunity to false turn-on by dV/dt• High commutation capability with

maximum false-trigger immunity• High ruggedness and reliability• Triggering in three quadrants only



NXP SEMICONDUCTORS

Wireless charging coil boosts efficiency, saves space,meets wireless-power standards

Attention to design details, and precision manufacturing, enhance the energy-harvesting capabilities of the IWAS-3827EC-50 wireless-charging coil

The Vishay IWAS-3827EC-50 receivingcoil for wireless charging of 5V portableelectronics achieves efficiency of morethan 70% for applications up to 10W,and has dimensions of 38mm x 27mmmaking it 33% smaller than the standard48mm x 32mm IWAS-4832FF-50.

The coil complies with Wireless PowerConsortium (WPC) specifications, and isconstructed from high-saturation powderediron allowing performance to be unaffected bypermanent locating magnets that may bepositioned nearby. The coil also features high-permeability shielding and effectively preventscharging flux from interfering with sensitivecomponents or batteries. As an alternative toferrite-based solutions, which can saturate inthe presence of a strong magnetic field, the

IWAS-3827EC-50 offers a magnetic saturationof 50% at 4000 Gauss.

The device features inductance of 10.7µH at200kHz with a ±5% inductance tolerance,DCR of 183mΩ at 25°C, and typical Q of 30at 200kHz. The receiving coil features a leadlength of 50mm and tinned length of 10mm.

APPLICATIONS• Wireless charging of 5V portable

electronics • Wireless power-receiver applications

to 10W

FEATURES• WPC compliant • High-permeability shielding • 50% magnetic saturation at 4000 Gauss • Durable construction



VISHAY

The BTA410-800CT is part of NXPSemiconductors’ large portfolio ofthree-quadrant Hi-Com triacs coveringvoltage ratings from 200V to 1000V,and providing high surge capability,high operating junction temperatureand high noise immunity foroptimum performance indemanding applications.

The BTA410-800CT handleson-state current up to10A and peak off-state voltage of800V, and ishoused inthe SOT78(TO-220AB)package. It is intendedfor use in circuits where high static anddynamic dV/dt and high dI/dt can occur. It willcommutate the full RMS current at the

maximum rated junction temperature of 150°Cwithout the aid of a snubber. Key applicationsfor this device include those where the abilityto operate at a high junction temperature is akey requirement.

NXP’s planar process technology allowsstable and reliable operation at high junctiontemperatures, and is a key advantage shared

by all devices in this family. Inaddition, ensuring the largest

possible die size withinindustry-standardpackage dimensionsenables high surge-current capability in

addition to helpingreduce temperature rise

when passing high currents.The outstanding thermal

performance of these devices also allowsa wide trigger-current range. The BTA410-

800CT requires a high trigger current, up to35mA, for applications requiring high noiseimmunity. The BTA410-800ET, which hashigher sensitivity, can be triggered by a currentof less than 10mA and hence can becontrolled reliably using logic devices.

Quad-core communication processors maximise throughput indata-centre and industrial computing


The P5040/5021 deliver high performance for compute-intensive applications and support Freescale'sTrust Architecture version 1.1


APPLICATIONS• Routers and switches• Data-centre server appliances• Storage controllers• Aerospace systems• Test and measurement equipment• Robotics

FEATURES• Two 1600MT/s DDR3 controllers• Dual four-channel DMA controllers• Two 10Gbit/s Ethernet MACs• Two PCIe 2.0/3.0 controllers• QorIQ Trust Architecture 1.1


FREESCALE

Miniature LDO-regulator family saves PCB spaceand battery energy

NXP SEMICONDUCTORS

APPLICATIONS• Low-voltage electronics• Handheld devices• Digital still cameras• Portable media players

FEATURES• 300mA peak output current• Temperature watchdog• Current limiter• Integrated ESD protection of 10kV

human body model• Choice of three packages




EVALUATIONBOARDS AT my-boardclub.com/ftm

DETAILSON PAGE

25

Freescale has extended its QorIQ® P5communication platforms by addingthe P5040/P5021 quad-core devices,which integrate the highestperformance single-threaded cores inthe QorIQ portfolio to target compute-intensive and power-consciouscontrol-plane applications.

The latest additions tothe QorIQ P5 familydeliver the benefits of abalanced architecturecombining four high-performance 64-bite5500 PowerArchitecture® cores, atightly coupled low-latency memoryhierarchy, integratedaccelerators, andadvanced I/Ossupporting high-speedinterconnects such asPCIe®, XAUI and SerialATA®.

The NXP Semiconductors LD6806series of small-size Low-Drop-Out(LDO) regulators has a maximumvoltage drop of 60mV at 200mAcurrent rating, and provides achoice of 0.4mm-pitchCSP, DFN1410-6 (SOT886)leadless-plastic or SOT753(SOT23-5) gullwing surface-mount package options.

Targeting applications that requirehighly miniaturised circuitry and longbattery life, the devices accept an inputvoltage from 2.3V to 5.5V and produce a fixed

output voltage. A total of 14 output-voltagevariants are available, from 1.2V to 3.6V.

Designers also have the choice of two typesof output configuration. H-suffix devices havea high-ohmic state at the Output pin, whiledevices with the P suffix contain a pull-downswitching transistor providing a low-ohmic

output stage when the device isdisabled. All devices use the same

regulator design, and have typicalquiescent current of less than 0.1µAin shutdown mode helping toreduce power consumption andextend battery life.

Additional benefits of the LD6806family include fast start-up time of

200µs, low output-voltage noise of30µVRMS allowing designers to eliminatededicated noise-reducing capacitors, andPower-Supply Rejection Ratio (PSRR) of 55dB

Package Type Part Number forHigh Ohmic Output

Part Number forLow Ohmic Output Output-voltage Variants

WLCSP 4-bump LD6806CX4/xxH LD6806CX4/xxP 1.2V, 1.3V, 1.4V, 1.5V, 1.6V,1.8V, 2.0V, 2.1V, 2.2V, 2.3V,2.5V, 2.7V, 2.8V, 2.9V, 3.0V,

3.3V, 3.6VDFN1410-6 (SOT886) LD6806F/xxH LD6806F/xxP

SOT753 (SOT23-5) LD6806TD/xxH LD6806TD/xxP

at 1kHz. The devices also benefit from ESDimmunity of 10kV, human-body model andpower dissipation of up to 800mW.

hardware accelerators and network interfaces.The DPAA provides hardware acceleratorsincluding a frame manager, buffer manager,queue manager, 3-DES security engine andRAID5/6 engine.

This combination provides the foundation fordevelopers to increase system performancewhile reducing system development andthermal management costs. Supporting CPUoperating frequencies up to 2.4GHz, theselatest devices deliver up to four-times theperformance of previous-generation control-plane processors.

Additional features helping to maximiseprocessor and I/O throughput includehardware-assisted virtualisation supported byFreescale Hypervisor or third-party virtualisationsoftware, as well as the QorIQ Data-PathAcceleration Architecture (DPAA) for optimumscheduling of work to physical or virtual cores,



Advanced power package unlocks extra MOSFETperformance through top- and bottom-side cooling

The FairchildSemiconductorFDMS86300DC 80Vpower MOSFETcombines Fairchild’shighly efficientPowerTrench®

silicon process and advancedDualCool™ power-package technologyto achieve the best possible on-stateresistance while maintaining excellentswitching performance by ensuringextremely low junction-to-ambientthermal resistance.

DualCool technology enhances the thermalperformance of the standard PQFN packageby adding a large top-side source contact forextra cooling. The underside of the packagehas a large exposed drain contact, which canbe soldered to the board allowing heat to bedissipated into the PCB substrate. The topsidecontact can be used as a radiator, or can becoupled to a heatsink using thermal material,to maximise extraction of heat from theMOSFET die.

The enhanced cooling achieved throughDualCool technology allows theFDMS86300DC to handle continuous draincurrents up to 60A. The device achieves verylow on-state resistance of 3.1mΩ, at 10Vgate-to-source voltage and 24A drain current,within the standard 5mm x 6mm Power 56package footprint.

APPLICATIONS• Synchronous rectifier for DC/DC converters• Telecom secondary-side rectification• High-end servers and workstations

FEATURES• 80V breakdown voltage• 60A continuous rated drain current• Junction-to-case thermal resistance:

• 2.3°C/W (top-side drain)• 1.0°C/W (bottom-side drain)

• 100% UIL tested




D series high-voltage MOSFETs deliver next-generationswitching and on-state performance

Vishay D series MOSFETs further enhance switching and conductionperformance in the 400V-500V class

Vishay Siliconix® D series high-voltageN-channel power MOSFETs feature anew high-voltage stripe technologythat allows a smaller die size andterminations, reducing gate charge by50% compared to other devices, whilealso achieving low on-state resistancefor increased efficiency and powerdensity.

Seventeen devices are available, offeringvoltage ratings of 400V, 500V and 600V, andmaximum current from 3A to 36A, in a widerange of packages. On-state resistance values

as low as 0.17Ω, 0.13Ω, and 0.34Ω for 400V,500V and 600V devices, respectively, translateinto extremely low conduction and switchinglosses saving energy in high-power, high-performance switched-mode applications. APPLICATIONS

• Server/telecom power systems• Welding/plasma-cutting equipment • Battery chargers• Lamp ballasts• Semiconductor manufacturing equipment• Induction heaters

FEATURES• High body-diode ruggedness• UIS avalanche-energy rating• Low area-specific on-state resistance• Low input capacitance



VISHAY The low gate charge enables higher switchingspeeds and also lowers input capacitance,which helps to simplify design by reducing thedemands on gate-drive circuitry. With gatecharges down to 9nC for the 400V devices,6nC for the 500V devices, and 45nC for the600V devices, the D series MOSFETs achievegate-charge x on-state resistance Figures OfMerit (FOM) down to 7.65Ω-nC, 15.6Ω-nCand 12.3Ω-nC, respectively. These values arethe best-in-class for MOSFETs used in power-conversion applications.

Part Number Voltage Drain Current(@ 25°C)

On-state Resistance(max. @ VGS = 10V)

Gate-charge Package

SiHP/F6N40D 400V 6A 1.0Ω 9nC TO-220/TO-220F


SiHG/P25N40D 400V 25A 0.17Ω 44nC TO-247/TO-220

SiHU/D3N50D 500V 3A 3.0Ω 6nC IPAK (TO-251)/DPAK (TO-252)

SiHD/P5N50D 500V 5A 1.5 10nC TO-252/TO-220

SiHF/U5N50D 500V 5A 1.5Ω 10nC T-Max®/TO-251


SiHG460B 500V 20A 0.25Ω 85nC TO-247AC

SiHP/G17N60D 600V 17A 0.34Ω 45nC TO-220/TO-247AC


Gen IV and Medium Voltage/ThunderFET MOSFETs deliver high efficiency for 30V to 150V applications

Vishay Siliconix® continues to extendthe performance of its power MOSFETsin 30V and 40V-to-150V ratings, usinglatest-generation processes andadvanced power packages to enhancekey metrics such as energy efficiency,switching performance and reliability.


The SiRA0xDP and SiSA04DN are 30V N-channel MOSFETs that utilise Vishay’s fourth-generation high-density TrenchFET®

technology. Housed in 6.15mm x 5.15mmPowerPAK® SO-8 or a 3.3mm x 3.3mmPowerPAK 1212-8 package, respectively,these devices achieve the industry’s best

on-state resistance of 1.35mΩ at a gate-sourcevoltage of 4.5V. These fourth-generationTrenchFETs also have very low gate charge,allowing them to offer outstanding Figures ofMerit (FOM) down to 56Ω-nC at 4.5V.

Spanning medium-voltage ratings from 40V to

APPLICATIONS• High power-density DC/DC converters• Synchronous rectifiers• Synchronous buck converters• Power OR-ing

FEATURES• Thermally advanced PowerPAK package• RG and UIS tested• QGD/QGS ratio of 0.5 or less (Gen IV

TrenchFET)



VISHAY

Device Family VoltagePackage

SO-8 PowerPAK SO-8 PowerPAK SO-8L

PowerPAK1212-8

PowerPAK SC-70

TrenchFET GenIV 30V –

SiRA00DP– SiSA04DN –SiRA02DP

SiRA04DP

MediumVoltage/ThunderFET

40V – SiR640DP – – –60V – SiR662DP – – –

80V –SiR826DP

SiJ482DP SiS468DN –SiR880DPSiR880ADP

100V

Si4056DY Si7454DDP

–

SiS892ADN

SiB456DK

Si4190ADY SiR804DP SiS890DNSi4090DY Si7456DDP –

– SiR846ADP SiR878ADP –– SiR870ADP –– SiR882ADP SiR876ADP –

150V – SiR872DP – – –

Surface-mount power MOSFET enhances efficiencyand switching performance

APPLICATIONS• Primary switch in isolated DC/DC

converters• Synchronous rectifiers• Load switches

FEATURES• Junction-temperature range:

-55°C to 150°C• 120A maximum pulsed drain current• 5mΩ on-state resistance (@ VGS = 8V,

ID = 19.5A)• 100% UIL tested• 228mJ single-pulse avalanche energy




The FDD86540 is a 60V, 50A N-channelPowerTrench® MOSFET housed ina TO-252 DPAK surface-mount package, and isoptimised for low gatecharge, low on-stateresistance, fastswitching speed andfast body-diode

Designers can takeadvantage of this device’sexcellent switching andconduction characteristics to increaseoverall energy efficiency and reduce switch-node ringing in DC/DC converters.

The FDD86540 can be used in eithersynchronous or conventional switched-modePWM controllers.

When operating with gate-to-sourcevoltage of 10V and drain current of

21.5A, the FDD86540 has verylow on-state resistance of

4.1mΩ. The low typicalgate charge of

54nC and lowgate-to-drain

‘Miller’ chargeallow the use of

high switchingfrequencies with low

switching losses.The FDD86540 can operate

with gate-to-source voltage up to amaximum of 20V, and is 100% UIL tested

and avalanche rated.

150V, Vishay’s Medium Voltage/ThunderFET®

family comprises 17 N-channel devices.Advanced process technology enables on-state resistance to be specified at VGS of 4.5V,giving designers the flexibility to use low-cost5V driver ICs. The family achieves theindustry’s lowest on-state resistance and FOMfor 4.5V-rated devices in the 40V to 150Vrange. Medium Voltage/ThunderFET MOSFETsare available in a choice of standard gull-wingSO-8, PowerPAK SO-8, PowerPAK 1212-8 orultra space-saving PowerPAK SC-70 packages.

The PowerPAK 1212-8 package has afootprint one-third the size of the standard SO-8, delivering comparable efficiency with asignificant space saving. The PowerPAK SC70package, which occupies only 4mm2, is 86%smaller than the SO-8 and so is ideal forextremely space-constrained applications.

30V and 40V-150V MOSFETs deliver performance gainsin space-saving power packages



Isolated DC/DC converters enable true point-of-loadperformance with higher density

APPLICATIONS• Power-over-Ethernet (PoE) power supplies• Communication equipment• Telecom systems• Network power

FEATURES• Up to 60W isolated DC/DC conversion in

0.57in2 area• Input-voltage range:

36V DC to 75V DC, 16V DC to 50V DC• Efficiency up to 88%• Proprietary ‘double-clamped’ ZVS buck-

boost topology• Proprietary isolated magnetic feedback• On/off control, positive logic• Over-temperature protection




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VICOR

Vicor Cool-Power® isolated DC/DCconverters are Power-Supply in aPackage (PSiP) devices that enabledesigners to replace thecombination of an isolatedIntermediate Bus Converter(IBC) and non-isolatedPoint-of-Load (POL) converterwith a single, energy-efficientpower-conversion stageproducing a regulated low-voltageDC output from a nominal 24V, 28Vor 48V DC input.

The Cool-Power family uses Zero-VoltageSwitching (ZVS) to achieve high conversionefficiency, and integrates magnetics, power-semiconductor ICs, MOSFETs and passivecomponents in a single package using Vicor’sadvanced IC-design expertise. This allows

designers to retain the board-space and costadvantages associated with an IntermediateBus Architecture (IBA).

Compared to a conventional IBA comprisingan isolated IBC with non-isolated POLs, which

cannot guarantee the most energy-efficientsolution, Cool-Power isolated DC/DC

converters with ZVS can help toreduce power-supply cost, save

board space and increase powerdensity. Devices such as the

PI3101 and PI3106consolidate the required

isolation, conversion,and regulation in a singleconversion stage directlyat the load.In addition to enabling

higher efficiency and smallerboard space, by reducing

the number of power-conversion stages, this approach also enablesrouting of higher voltages on the circuit board.Using a higher-voltage bus lowers I2R losses,which ultimately translates into higher

Family PI3101 PI3106-01-HVIZ PI3106-00-HVMZ

Features High-density, isolated DC/DC converter

High-density, isolated DC/DC converter

MIL-COTS high-density, isolatedDC/DC converter

Input Voltage 48V (36V – 75V) 24V (18V – 36V) 28V (16V – 50V)Output Voltage 3.3V regulated 12V regulated 12V regulatedPower 18A / 60W 4.2A / 50W 4.2A / 50W

Advanced LED-lighting IC enhances precision and flexibilitywith smart digital control

NXP SEMICONDUCTORS

APPLICATIONS• LED spotlights• LED downlights• Wall sconces• LED tubes• LED retrofit bulbs

FEATURES• Primary-side sensing• ±1.5% line regulation• ±3% LED-current accuracy• Integrated NTC for external over-

temperature protection




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The NXP Semiconductors SSL21101TGreenChip™ LED driver with SmartDigital Control (SDC) technologyincorporates a digital core within atraditional analogue system to helpengineers to optimise efficiency,current regulation and system costand provide greater flexibilitythan a pure analogue solution.

Targeting non-dimmable, high-performance LED applicationsup to 15W, the SSL21101T is asingle-stage solution designed toperform in flyback or buck-boostconfigurations with very high efficiency of up to90% and with highly accurate control of theoutput current. Its SDC feature offers twomodes optimised for specific regional

regulatory requirements. In high power-factormode, the power factor is higher than 0.95and Total Harmonic Distortion (THD) is limitedto under 20%. Alternatively, the low-ripplemode lowers the LED-current ripple below 1%and allows use of smaller electrolyticcapacitors to achieve very compact designs in

applications that are exempt fromIEC61000-3-2 harmonic-control

requirements.Featuring a high level of

integration and functionalityin a small footprint, the

SSL21101T includes a high-voltage power switch, circuitry

enabling start-up directly from therectified mains voltage, and

comprehensive protection featuresincluding short-winding protection,

internal over-temperature protection, LEDshort-/open-circuit protection and Under-

Voltage Lock-Out (UVLO). Designs can becompleted using as few as 18 components,resulting in a very low bill of materials cost.

efficiency. The PI3101 and PI3106-01/00 areavailable in a space-saving surface-mount22mm x 16.5mm x 6.73mm package thatoccupies around 50% smaller board area thanconventional solutions.


PIN photodiodes enhance sensitivity andswitching time

The latest-generation PIN photodiodes deliver fast, clear response to visible light or infrared

TEFD4300 and TEFD4300F high-speedsilicon PIN photodiodes from Vishayhave high radiant sensitivity and fastswitching times, and simplifyoptoelectronic design by providing ahigh reverse photocurrent of 17µA and a ±20° angle of halfsensitivity.

The devices are housedin T1 plastic packagesfeaturing 3mm lenses.Optimised for infraredand visible light sources,the TEFD4300 is a clearepoxy device with asensitivity range of350nm to 1120nm. Foruse with sources in theinfrared wavelength rangeof 770nm to 1070nm, theTEFD4300F is a black

epoxy device with a daylight-blocking filtermatched with 850nm to 950nm IR emitters.

The photodiodes offer fast switching timesdown to 10ns at low load-resistor values,0.1%/K temperature coefficient, temperaturerange of -40°C to 100°C, and a 950nmwavelength of peak sensitivity. The devices arepackage-matched with Vishay’s VSLB3940,TSUS4300, and TSAL4400 infrared-emitterseries.

VISHAY

APPLICATIONS• Data transmission• Photo interrupters• Optical switches• Encoders• Position sensors

FEATURES• 100ns/100ns rise/fall time• 1V typical forward voltage• 60V maximum reverse voltage• 3nA maximum reverse dark current• 15µA short-circuit current




12

D E S I G N N O T E



Voltage sensing in electric and hybrid vehicles

Accurate monitoring of motor-drive voltages and batteryvoltage is essential in electric and hybrid vehicles. Thisdesign note from Avago Technologies shows how the latestisolation amplifiers provide effective protection against thenoise and potentially damaging voltage and current effectsthat characterise the automotive electrical environment.

Voltage sensing is required in the motor drive and battery-monitoringsystems of electric and Hybrid Electric Vehicles (HEV), to help ensureoptimum vehicle performance and to provide status information for users.Figure 1 shows how isolation amplifiers, such as the Avago ACPL-782Tor ACPL-C87AT/C87BT, are used in motor-drive monitoring to isolateanalogue sensors and the processor monitoring the rail voltage from theeffects of high-speed, high-voltage transients caused by the switching ofhigh currents in the inverter.

Avago’s isolation amplifiers use a sigma-delta architecture to convertthe differential analogue input into digital pulses to be transmittedoptically across the insulation barrier. Extremely low input-outputcoupling capacitance (CI-O) provides excellent common-mode transientrejection, ensuring that all optically isolated digital pulses are transmittedwithout missing bits.

Battery-stack voltage measurementIn battery-voltage measurement, an ACPL-C87AT/BT isolation amplifieris used with an optocoupler such as the ACPL-M49T, as shown inFigure 2. The high-voltage input is sensed by precision voltage-dividerresistors. The ratio of the voltage divider is determined by the allowableinput range of the isolation amplifier (0V to 2V). This small analogue inputgoes through a 39Ω/10nF anti-aliasing filter. Inside the isolation amplifierthe analogue signal is digitised and optically transmitted to the outputside. The detector then decodes the signal for conversion back toanalogue. An op-amp converts the output differential signals of theACPL-C87AT/BT to a single-ended format. A second op-amp can beused to improve linearity.

Automotive-grade isolationThe ACPL-C87AT, ACPL-C87BT and ACPL-782T are part of Avago’sR2Coupler™ series, which is engineered to provide safe insulation, highcommon-mode transient rejection and precision analogue sensing inautomotive applications. Table 1 describes key features of these devices.

Safe insulationThe tough automotive environment calls for components offeringexcellent isolation and insulation characteristics, as well as high accuracywithin a noisy environment, reliability, low power consumption andgalvanic isolation. Avago’s R2Coupler devices feature a thick triple-insulation layer that allows a high insulation rating. With up to 1414Vpeakworking voltage and 8000Vpeak transient over-voltage specifications, theymeet the insulation requirements of most automotive applications.

AccuracyIn addition to their sigma-delta ADC architecture, R2Coupler devices alsoimplement chopper-stabilised amplifiers and a fully differential circuittopology to provide unequalled isolation-mode noise rejection and highgain accuracy and stability. The total device error is the sum of gain,nonlinearity, offset-voltage error and temperature drifts; these errors canbe further reduced or removed with calibration.

Reliability, power saving, isolationTo ensure reliable operation the devices use automotive-grade LEDs thatare specially designed and manufactured for a long operating lifetimeover the temperature range of -40°C to 125°C and do not degradeacross the typical mission profile of current and future road vehicles.

The ACPL-C87AT and ACPL-C87BT have a power-saving shutdownfunction that sets the output low and reduces typical supply current to6µA. The shutdown can be controlled from the host microprocessorthrough an optocoupler.

R2Coupler isolation amplifiers have a Distance Through Insulation (DTI) of0.5mm, owing to their thick triple-insulation layer separating input and outputsides, and also have input-output momentary withstand voltage ratings (VISO)of 3750VRMS for ACPL-782T and 5000VRMS for ACPL-C87AT/ACPL-C87BT.

ConclusionAvago’s R2Coupler isolation amplifiers feature reinforced insulation andincreased reliability, as well as low input-output coupling capacitanceensuring high common-mode transient immunity. The accuracy of thesigma-delta architecture allows the ACPL-C87AT, ACPL-C87BT andACPL-782T to be used in automotive voltage-sensing applications suchas inverter monitoring and battery-stack measurements.

AVAGO TECHNOLOGIES

Fig. 2: Battery measurement using isolation amplifier

Fig. 1: HEV electric motor drive system

Avago IsolationAmplifier Gain Accuracy Non-Linearity Shutdown

Feature Packaging

ACPL-C87BT 0.50% 0.05% Yes SSO-8ACPL-C87AT 1% 0.05% Yes SSO-8ACPL-782T 2% 0.00% No DIP-8

Table 1: Key features of Avago’s R2Coupler™ isolation amplifiers

High-accuracy voltage sensors add special featuresfor automotive monitoring

Avago Technologies’ ACPL-C87AT/C87BTisolation sensors combine superioroptical-coupling technology with asigma-delta ADC, chopper-stabilisedamplifiers and a fully differential circuittopology to provide unequalledisolation-mode noise rejection, lowinput-offset voltage of -0.3mV, highgain accuracy and high stability.

The devices are part of Avago’s R2Coupler™

family of optocouplers, and are manufacturedin a TS16949-certified manufacturing facility.They are PPAP supported and qualified toAEC-Q100 Grade 1 meeting the strict qualityand robustness requirements of automotivemarkets. R2Coupler devices are also suitablefor high-temperature industrial applications.

The ACPL-C87AT has ±1% gain tolerance,while the ACPL-C87BT has ±0.5% gaintolerance. Both devices are suitable for high-precision DC-voltage sensing in electronicmotor drives, DC/DC and AC/DC converters,and battery-monitoring systems.

The devices have high input impedance andare able to operate from an analogue inputvoltage of up to 2.46V.

Special features include a shutdownfunction, which supports power-saving designand can be controlled from an external sourcesuch as a microcontroller. In addition,common-mode transient immunity up to15kV/µs ensures high precision and stabilityfor monitoring DC-rail voltages accurately inhigh-noise motor-control environments.

This galvanic safe-isolation solution is deliveredin a compact, surface-mount Stretched SO-8 (SSO-8) package that meets worldwideregulatory safety standards.

Read Avago’s Design Note on page 13,‘Voltage sensing in electric and hybrid vehicles’.

AVAGO TECHNOLOGIES

APPLICATIONS• Battery-pack voltage sensing• DC/DC-converter voltage sensing• Motor-inverter DC-bus voltage sensing• Charger-output voltage sensing• Isolation interface for temperature sensing

FEATURES• 0.05% nonlinearity• 25ppm/°C gain drift vs temperature• 100kHz bandwidth• Worldwide safety approvals:

• UL 1577 (5000 VRMS/1 min.)• CSA• IEC/EN/DIN EN 60747-5-5 (pending)



Automotive ElectronicsStatistics regarding the electronics content of modern cars are fastbecoming redundant, as the future points towards fully-electricplug-in rechargeable vehicles.As car makers and governments work

towards a future without the combustion engine,current model development is utilisingelectronics and software to make compellingnew features accessible to a broad range ofbuyers. Key targets lie in improving efficiency,reliability, safety and driver aids. As analyst IHSiSuppli noted earlier this year, major US,European and Japanese car brands are alreadypositioning Advanced Driver-AssistanceSystems (ADAS), such as forward-sensingcollision avoidance, at mid-market prices. Fuelefficiency, also, is improving significantly withadvances in electronic engine management, andusing bus infrastructures such as CAN andFlexRay to increase economy by significantlyreducing overall weight.This month’s Application Spotlight has a selection of components

and modules addressing up-to-the-minute demands such as vehiclenetworking, power control and telematics. Freescale’s MC33662 LINphysical-layer device, featured on page 21, and MC33903/4/5

system-basis chips, on page 23, support the latest CAN/LINstandards and enable energy-efficient sensor networking. TheMPC564xL MCUs, featured on page 19, support FlexRay and are

able to manage functions such as chassisand steering controls, as well as ADAS andhybrid inverter controllers.Advances in power-control electronics,

such as MOSFETs, continue to focus onmaximising energy efficiency and switchingperformance, while increasing ruggedness forgreater reliability. International Rectifier hasfurther extended its families of automotiveMOSFETs, described on page 16, while NXPSemiconductors’ Trench 6 family, featured onpage 20, promises a high-reliability solutionfor virtually every application in the car. Alsoincluded in this Application Spotlight are thelatest devices such as regulators, gatedrivers, transient protectors and ignition-coildrivers from well-known manufacturers.

The Design Note, on page 13, describes how Avago’s newisolation amplifiers, featured below, provide the insulation safety andsignal accuracy needed for voltage sensing in advanced hybrid andelectric vehicles.

A P P L I C A T I O N S P O T L I G H T – A U T O M O T I V E E L E C T R O N I C S

14 F R E E D E V E L O P M E N T K I T S A T W W W . M Y - B O A R D C L U B . C O M



Low-distortion analogue switch has digital featuresto simplify circuit design

The NX3L4051 digitally-controlled analogue switch is ideal forinfotainment applications

The NXP Semiconductors NX3L40518-channel analogue switch has goodon-state properties as well as highnoise immunity, a wide supply-voltagerange and features that help to simplifycircuit design.

The low typical on-state resistance of 0.5Ω, at4.3V VCC, and resistance variation of less than0.13Ω ensure minimum attenuation anddistortion of transmitted signals. The supply-voltage range of 1.4V to 4.3V allows operationfrom any low-voltage CMOS rail, while thecontrol input is able to respond to signalsabove the supply voltage. The deviceconsumes very low supply current, even whenthe input is below the supply voltage.

By providing low-threshold digital inputs, theNX3L4051 can be controlled using 1.8V logicsignals in 3.3V applications without drawingsignificantly higher supply current. This makesit possible to switch 4.3V signals using a 1.8Vdigital controller with no need for logic-leveltranslation.

The NX3L4051 can be used as an analogueor digital multiplexer/demultiplexer, or forsignal-gating duties. It has three digital Selectinputs, eight independent I/Os, and onecommon I/O. All eight switches share anEnable input which can be used to overridethe Select inputs and put all switches into ahigh-impedance OFF state. Schmitt-triggeraction at the Select and Enable inputs makesthe circuit tolerant to slow input rise and falltimes across the entire supply-voltage range.

NXP SEMICONDUCTORS

APPLICATIONS• In-car audio and multimedia• Test and measurement equipment• Portable media players• Handheld communication devices

FEATURES• 1.7Ω on-state resistance at VCC = 1.4V• 350mA maximum continuous current at

3.3V supply• Break-before-make switching• ESD protection:

• 1kV CDM (AEC-Q100-011 revision B)• 8kV for switch ports (IEC61000-4-2

contact discharge)



AEC-Q100 qualified transient-suppressionfamily protects high-speed data interfaces

Three types of RClamp TVS devices provide protection for themajority of automotive interfaces

Semtech has a portfolio of AEC-Q100automotive-qualified Transient-VoltageSuppressor (TVS) devices forprotecting high-speed data lines, USBports and Automotive Ethernet portsagainst over-voltage threats due toElectrostatic Discharge (ESD), Cable-Discharge Events (CDE), and ElectricalFast Transients (EFT).

The RClamp®0531TQ features a 5V workingvoltage with a maximum capacitance of only0.80pF, allowing it to be used on circuitsoperating in excess of 2.5GHz without signalattenuation. Each device will protect one high-speed line, giving designers the flexibility toprotect single lines in applications where arraysare not practical. The RClamp0531TQ ishoused in a 2-pin SLP1006P2T packagemeasuring 1.0mm x 0.6mm x 0.4mm.

The RClamp®0582BQ is optimised toprotect automotive USB ports from dangerousin-vehicle ESD threats. It features a high peakpulse-current capability of 15A, tested with8/20µs pulse, and presents I/O-to-GND

capacitance of less than 1.2pF. Housed in acompact SC-75 (SOT-523) package, theRClamp0582BQ is a two-channel device thatprovides flexibility to protect one bidirectionalline or two unidirectional lines.

The µClamp®3311PQ for protectingautomotive Ethernet interfaces is housed in a

SEMTECH

APPLICATIONS• Automotive Ethernet interfaces• Automotive USB interfaces• Automotive multimedia touch-points• Advanced Driver-Assistance Systems

(ADAS)

FEATURES• Exceeds IEC 61000-4-2 ESD immunity

requirements• Features low clamping voltage• Single-line bidirectional protection

(RClamp0531TQ, µClamp3311PQ)• Surge rated, two-line protection

(RClamp0582BQ)



2-pin SLP1006P2 package measuring 1.0mmx 0.6mm x 0.5mm. This device allowsdesigners to protect single lines in applicationswhere arrays are not practical. The deviceuses Semtech’s proprietary EPD processtechnology, which provides low standoffvoltages with significant reductions in leakagecurrent and capacitance over siliconavalanche-diode processes. The trueoperating voltage of 3.3V ensures superiorprotection when compared to traditional PN-junction devices.



Mixed-signal automotive MCU takessystem integration to the next level

The S12VR64 is optimised for automotive applications, including 12Vinputs and support for LIN

The S12VR64 is the first mixed-signalautomotive microcontroller in Freescale’sS12 MagniV portfolio, combiningprecision high-voltage analoguefunctions and proven digital-processingresources to enable safe and reliablevehicle-networking solutions meetingtight size and cost constraints.

The microcontroller family is based on aprocess combining non-volatile memory, digitallogic and 40V CMOS analogue components ina monolithic solution. The S12VR64 is featuredfor networked motor-control applications suchas window lifters, and integrates analoguecomponents including an automotive voltageregulator, LIN physical layer, low-side drivers,high-side drivers and 12V inputs for switchmonitoring.

The high-voltage analogue functions arecapable of withstanding harsh transients,which can happen during load-dump events,and are integrated with the industry-proven

16-bit S12 CPU and memory subsystemconsisting of ECC-protected Flash memoryand real EEPROM. This S12 CPU is fullycompatible with the S12G family of cost-effective, highly integrated microcontrollers.This compatibility also extends to theS12VR64’s digital peripherals, which includean SPI port, SCI modules, PWM and timermodules.

In addition, the S12VR64 combines systemelements that effectively save valuable PCBspace, simplify design, increase overall systemquality and reduce cost.

These include temperature sensing, an internaloscillator, and watchdog and wake-up blocks.

An S12VR service pack is available forCodeWarrior® Development Suite 5.1, enablingdevelopers to start new projects quickly basedon the S12VR64 and forthcoming familymembers. Further developer resourcessupporting the S12VR family include referenceLIN-driver software and the S12VR64EVBevaluation board.

FREESCALE

APPLICATIONS• Door controls• Window lifters• Sunroof controllers• Seat adjusters• Smart actuators

FEATURES• Up to 64kbyte Flash with ECC • 512bytes EEPROM with ECC • 2kbytes on-chip SRAM• High-voltage inputs




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55V planar MOSFETs in insulated FullPakpackage simplify hardware design

International Rectifier hasextended its range ofautomotive-qualified powerMOSFETs with a family of55V planar devices housedin a rugged TO-220 FullPakpackage, which eliminatesthe need for additionalinsulating hardware tosimplify design and improveoverall system reliability.

The family provides a choice of standard orlogic-level gate drive, and both N-channel and

P-channelconfigurations areavailable. The devices areideal for automotiveapplications thatneed rugged,reliable MOSFETsto switch highlyinductive loads.With low on-stateresistance values,down to 8mΩ, they

INTERNATIONAL RECTIFIER

APPLICATIONS• Automotive pumps• Cooling systems• General BLDC-motor drives

FEATURES• 2.5kVRMS isolation• 4.8mm sink-to-lead creepage distance• 175°C operating temperature• Fully avalanche rated



Part Number Voltage On-state Resistance (max. @ VGS = 10V)

Drain Current (max. @ TC = 25°C)

Gate Charge (typ. @ VGS = 10V)

Standard gate-drive devices:

AUIRFI3205 55V 8.0mΩ 56A 113nCAUIRFIZ44N 55V 24mΩ 28A 43nCAUIRFIZ34N 55V 40mΩ 19A 23nCAUIRFI4905 -55V 20mΩ -74A 120nC

Logic-level gate-drive device:

Part Number Voltage On-state Resistance (max. @ VGS = 4.5V)

Drain Current (max. @ TC = 25°C)

Gate Charge (typ. @ VGS = 10V)

AUIRLI2505 55V 8.0mΩ 58A 130nC

also perform well in linear applications.IR’s automotive MOSFETs are subject to

dynamic and static part-average testingcombined with 100% automated wafer-levelvisual inspection as part of IR’s automotivequality initiative targeting zero defects. AEC-Q101 qualification requires that there isno more than a 20% change in on-stateresistance after 1,000 temperature cycles oftesting. However, in extended testing IR’s newAU bill of materials demonstrated a maximumshift of less than 10% at 5,000 temperaturecycles, showing the strength and ruggednessof the bill of materials.

IR's latest 55V MOSFETs also enhance reliability and allowfaster assembly



Ignition-coil drivers deliver high switching energywith reduced power dissipation

Fairchild Semiconductor EcoSPARK® 2ignition-coil driver IGBTs utiliseadvanced silicon technology to deliverperformance and robustnessequivalent to competing devices, withthe advantages of reduced powerdissipation and a 60% smaller package.

Fairchild’s EcoSPARK drivers use Self-Clamped Inductive Switching (SCIS) to activatethe coil without applying excessive stress onignition-system components. The latest-generation EcoSPARK 2 devices, theFGD3040G2 and FGD3440G2, achieve up to20% lower collector-emitter saturation voltagebut have no reduction in SCIS energy. Thisenables engineers to maintain effective controlof the coil while at the same time reducingpower dissipation, heatsink requirements andoperating junction temperature.

Both the FGD3040G2 and FGD3440G2 canbe used in advanced multi-spark, high-currentignition systems with lean-burn requirements,enabling engineers to deliver competitivelypriced solutions that help meet demands forincreased fuel efficiency and lower emissions.


Next-generation 8-bit MCUsenhance peripheral integration

PIC12F(HV)752 microcontrollers offer a choice of standard or high-voltage operation, with peripherals for automotive-controlapplications

MICROCHIP

APPLICATIONS• Automotive ignition-coil driver circuits• Coil-on-plug applications

FEATURES• Qualified to AEC-Q101• SCIS Energy:

• 300mJ at TJ = 25°C (FGD3040G2)• 335mJ at TJ = 25°C (FGD3440G2)

• Logic-level gate drive


APPLICATIONS• Battery charging• LED-lighting controls• Electronic lamp ballasts• Power-conversion systems• General-purpose system control

FEATURES• 16-bit and 8-bit timers• Internal 8MHz oscillator• Sleep mode• System-protection functions• Programmable code protection





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Microchip PIC12F(HV)752 8-bit MCUsfeature next-generation analogue anddigital peripherals including aComplementary-Output Generator(COG) that provides non-overlapping,complementary waveforms for inputssuch as comparators and Pulse-WidthModulation (PWM) peripherals.

The advanced EcoSPARK 2 technologyenables the devices to be housed in theindustry-standard DPAK surface-mount powerpackage, which is 60% smaller than theD2PAK package typically used for existingalternative devices.

The COG also allows dead-band control, autoshutdown, auto reset, phase control andblanking control. In addition, the new PIC® MCUsfeature 1.75kbyte of self read-write programmememory, 64bytes of RAM, an on-chip 10-bitADC, a 5-bit DAC, a capture-compare PWMmodule, two high-performance comparatorswith response times down to 40ns, and two50mA-capable I/Os. These features supportmany opportunities for engineers to increaseoverall system capabilities and reduce costs.

The PIC12HV752 is a high-voltage variantincorporating a shunt regulator, which allowsoperation from 2V to an unspecified user-defined maximum voltage level, with less than2mA operating current. This high-voltagevariant is ideal for cost-sensitive applicationswith high-voltage power rails. Additionally, the4-channel, 10-bit ADC can be used toimplement various sensors and mTouch™ sensingapplications, including capacitive touch.

Multi-channel devices meet USB3.0 ESDand over-current protection requirements


Littelfuse SPA™ TVS-diode arrays andPositive Temperature-Coefficient (PTC)devices, together, provide ESD andshort-circuit protection for high-speedUSB interfaces in applicationsincluding in-car infotainment and after-market audio products


The high data-transfer rate of 5Gbit/s, specifiedby the latest USB3.0 standard, demands areduction in channel capacitance to avoidsignal distortion, calling for new, ultra low-capacitance ESD-protection devices. Inaddition, USB3.0 interfaces have extradifferential data pairs and hence require moredata lines to be protected. This can be bestserved using diode-array devices, whereasdiscrete devices have been adequate for

protecting USB2.0ports.

The Littelfuse SPAfamily of TVS-diodearrays absorbtransients usingcurrent-steering diodesand also clamp thevoltage level using a

Zener diode. Among the devices available, theSP3011 provides multi-channel protection in asingle device, while the SP3012 and SP3003are used together as a two-device solution forprotecting the six data lines. The SP3003protects the legacy D+/D- pair while theSP3012, which has extremely low dynamicresistance of 0.4Ω, protects the two super-speed differential pairs. This provides best-in-class clamping performance for USB3.0chipsets or translator ICs that are verysensitive to over-voltage events.

Over-current protection can be implemented

by inserting a PTC device in the USB3.0supply-voltage (VBUS) connection, in circuitsusing bus-transceiver or power-managementICs without current-limiting features. TheLittelfuse 0603L150SLYR is the smallest devicecapable of supporting the required current of0.95A at the maximum design temperature of60°C. For applications requiring a larger hold-current margin, the 1210L200SLYR holds1.29A at 60°C. For two-port applications, the1206L350SLYR can hold 2.19A at 60°C. Allparts are capable of tripping in less than fiveseconds at 8A fault current, allowing designersto meet the applicable safety considerations.

LITTELFUSE

APPLICATIONS• Enterprise servers• High-speed local storage devices• High-end PCs and notebooks• Studio equipment• Multimedia products

FEATURES• Small form factor• Ultra-low TVS capacitance• Low TVS clamping voltage• Low TVS dynamic resistance• Variant meeting battery-charging

specification Rev 1.2



Number of USB3.0 Ports Part Number Footprint Hold Current

(@ 20°C) Hold Current (@ 60°C)

Trip Time (@ 8A, 20°C)

MaximumResistance

1 0603L150SLYR 603 1.5A 0.95A 0.5 seconds 0.08Ω1 1210L200SLYR 1210 2A 1.29A 3 seconds 0.024Ω2 1206L350SLYR 1206 3.5A 2.19A 5 seconds 0.018Ω

Battery chargingRev. 1.2 1206L260SLTHYR 1206 2.6A 1.65A 4 seconds 0.026Ω

High-power gate driver maximises noise immunityfor vehicle electrical applications

Choose the FAN7171 for stable, reliable power switching and gatedriving

The Fairchild Semiconductor FAN7171is a high-performance gate driveroffering high drive capability andoutstanding noise immunity for use inautomotive DC/DC power supplies,inverters and actuators throughoutdiesel, petrol, hybrid and electricvehicles.

The FAN7171 uses High-Voltage IC (HVIC)technology, has a high drive capability of up to4A, and can be used with MOSFETs or IGBTsoperating up to 600V. It features a bufferedoutput stage implemented with NMOStransistors, which minimises cross conductionand enables designers to implement high-power systems offering outstanding energyefficiency and noise immunity.

Fairchild’s high-voltage process andcommon-mode noise cancellation enable thisdriver IC to operate reliably in the automotiveelectrical environment, which often contains

high dV/dt noise. The FAN7171’s high noiseimmunity, with a negative voltage swing (VS)down to -9.8V for a floating-supply voltage(VBS) of 15V, allows for improved designreliability and increased durability in challengingnoise environments. The driver also has anUnder-Voltage Lockout (UVLO) circuit, whichprevents malfunction when VBS is lower thanthe specified threshold voltage.


APPLICATIONS• Fuel-injection actuators• Valve actuators• Electric-vehicle traction drives• DC/DC power supplies

FEATURES• Qualified to AEC-Q100• Floating channel for bootstrap operation

to 600V• 4A/4A current source/sink capability• Common-mode dV/dt-noise cancelling

circuit• Output in phase with input signal• 8-lead Small-Outline Package (SOP)



USB is becoming a familiarsight in new cars

PTC devices are inserted in the VBUS connection to add over-current protection where required



Magnetic rotary position-sensing SoC maximisesaccuracy up to high rpm

The AS5132 is versatile, accurate over a widerange, and easy to design in

The AS5132, by ams, is a magneticrotary position-sensing system-on-chip,combining integrated Hall elements, ananalogue front-end and digital signalprocessing in a single device offeringaccurate angular measurement even atvery high rotation speeds.

The sensor is particularly well suited to use inindustrial and automotive systems containingBLDC motors, in which itoffers designers a small,robust and easily assembledposition-sensing solution. Itis highly resistant tointerference from straymagnetic fields.

The AS5132 improves onprevious generations ofmagnetic encoder bydynamically compensatingfor angular errors attributableto propagation delay.

Error compensation is achieved throughintegrated pre-commutation functions, whichenables engineers to reduce the loading onthe host microcontroller or vehicle Electronic-Control Units (ECUs), while retaining theflexibility to re-optimise the configurationdynamically in response to changes such asvariations in rotation speed.

In addition, the AS5132’s advanced signal-processing circuitry ensures low propagationdelays of less than 22µs. This ensures that theangle error is small even before pre-commutation is implemented.

In combination, the small propagation delayand advanced pre-commutation enable angle

measurements to beaccurate to within ±3° evenin motors rotating at speedsup to 80,000rpm. Thisenables consistently highlevels of torque over thewhole dynamic range, evenin high-speed applications.

The device providesadditional benefits includingincreased sensitivity to allowoperation in low-strengthmagnetic fields produced by

low-cost ferrite magnets, a simplified interfacefor easier integration, an external-clock modefor synchronising sensor and controllersystems, and a 3V-interface mode that savesengineers designing-in an external level shifter.

AMS

Dual-core microcontrollers combine safetyarchitecture with flexible feature integration

Qorivva safety MCUs integrate rich control and communicationperipherals

Combining functional safety featuresand a dual-core, dual-issue processorarchitecture alongside motor-controlperipherals and FlexRay™ support, theFreescale Qorivva MPC564xL MCUfamily is ideal for safety-criticalapplications such as electric-steeringcontrols, braking and chassis controls,and pre-crash detection.

The MPC564xL family is part of Freescale’sSafeAssure™ programme, which simplifies theprocess of achieving system compliance withfunctional safety standards in the automotiveand industrial markets. The microcontrollersintegrate two e200 Z4 32-bit PowerArchitecture® CPUs, and maintain dualprocessing spheres with independent DMA,interrupt controller, crossbar and Memory-Protection Unit (MPU) for logic-level faultdetection.

For applications requiring IEC 61508(Safety-Integrity Level 3) or ISO26262 (ASIL-D)functional safety, the two domains are able tooperate in lock-step mode, establishing an

vehicle electrification. Enabled by the newcross-triggering unit, the device allows controlof up to two brushless DC motors or multiplevalves with only minimum interrupt load.Additional features include the fault-collectionunit, FlexRay protocol, two 12-bit ADCs,eTimer units and a built-in hardware self test.FREESCALE

APPLICATIONS• Automotive BLDC-motor position control

(pumps, stop-start systems)• Position sensing in double-clutch BLDC

motors• Contactless rotary position sensing• Rotary user-interface switches• AC/DC motor-position control

FEATURES• 8.5 bits absolute angle measurement

resolution• U, V, W outputs for BLDC-motor block

commutation• Software-adjustable zero position


APPLICATIONS• PSI5 airbag system • 77GHz radar system • Adaptive cruise control• Vehicle dynamic and chassis control• Braking and stability control • Active suspension • Hybrid Electric-Vehicle (HEV) inverter

controller

FEATURES• Fault-collection unit• Memory error-correction coding• Motor-control library• Motor-control dead-time insertion and

skew correction





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environment for redundant processing andcalculations. Common-cause failurecountermeasures targeting power, clock anderror propagation are implemented to detectvarious failure modes.

For applications needing maximumperformance or software diversity, the twoprocessor domains can be statically switchedto operate independently in parallel and soexecute two instructions per clock cycle.

The MPC564xL family is designed tosupport actuator-control applications for



Low-noise automotive LDO regulatorstarget advanced infotainment applications

The ON Semiconductor NCV8570B is a200mA LDO voltage regulator featuringultra low-noise performance and highPower-Supply Rejection Ratio (PSRR)allowing use in imaging applicationssuch as lane-change detection warnings,as well as RF or audio equipment.

The key to the regulator’s low-noiseperformance is ON Semiconductor’s advancedBiCMOS process, which also results inexcellent dynamic performance as well as lowground current at no load and full load. Thelow ground current, as well as 1µA sleepmode, help to maintain high energy efficiency.

Designers also have the flexibility to optimisenoise performance by taking advantage of theregulator’s external Noise-reduction pin.Connecting a capacitor of 10nF or larger tothis pin improves noise performance andPSRR while also increasing the regulator turn-on time.

The excellent load-transient performance,wide operating voltage range from 2.5V to5.5V, and compact dimensions of the 2mm x2.2mm DFN6 package, make the NCV8570Bwell suited to use in battery-powered andportable applications. The NCV8570B is alsoavailable in a TSOP-5 package.

The NCV8570B is stable with small, low-value, low-ESR ceramic capacitors, allowingdesigners to minimise the total PCB spaceoccupied by the solution. The devicesavailable provide a fixed output voltage of1.8V, 2.8V, 3.0V or 3.3V.

ON SEMICONDUCTOR

APPLICATIONS• Cameras for lane-change detection and

reverse view• GPS modules• Portable/built-in DVD entertainment

systems• Satellite and HD radio

FEATURES• AEC−Q100 qualified and PPAP capable• 82dB PSRR @ 1kHz• 10µVRMS typical noise voltage @

VOUT = 1.8V• Active-discharge circuit• Current-limit and thermal-shutdown

protection• ±2.5% output-voltage accuracy over

load/line regulation and temperature



Automotive MOSFETs combine application flexibilitywith latest process advances

NXP has a Trench 6 MOSFET for almost every automotiveapplication

*The xRx field in the naming of NXP’s parts denotes the on-state resistance rating of the device: 1R3 stands for a maximum on-resistance of 1.3mΩ.

NXP Semiconductors is rolling out aportfolio of MOSFETs using its latestautomotive-grade technology, Trench6, at voltages of 30V, 40V, 60V, 80V and100V to deliver an optimised, high-reliability solution for virtually everyMOSFET socket in the car.

Currently, there are 48 D2PAK devices,providing designers with a choice of standard-voltage or logic-level gate drive in each voltagerating. The devices have low on-stateresistance, from 1.2mΩ in 30V standard-drivedevices, to 14mΩ in 100V logic-level variants.Offering true logic-level variants for everyproduct is a crucial feature, combined withbenchmark on-state resistance and threshold-

NXP SEMICONDUCTORS

APPLICATIONS• Solenoid control• Transmission control• Ultra high-performance power switching• Motor drives• Lamp drives

FEATURES• AEC-Q101 qualified• 120A rated drain current• 175°C temperature rating• Repetitive avalanche rated• SOT404 (D2PAK) package• Future package options to include

Power-SO8 (LFPAK56)



First 35 parts of NXP D2PAK portfolio in T6

Voltage Rating Number of Products Available

On-state ResistanceRange (max.) Gate Charge Indicative Part Numbers

30V 1 1.3mΩ 49.8nC BUK761R30-30E

40V 14 1.6mΩ-7.9mΩ 7.3nC-48.2nCBUK76xRx-40E*BUK96xRx-40E

60V 16 2.4mΩ-14mΩ 6.7nC-45.5nCBUK76xRx-60EBUK96xRx-60E

80V 2 3.8mΩ-4.2mΩ 37.5nC-51nCBUK763R8-80EBUK964R2-80E

100V 2 5mΩ-5.8mΩ 51nC-65nCBUK765R0-100EBUK965R8-100E

MOSFETs market over the past two years,Trench 6 is known to deliver the quality andreliability required to last the lifetime of the car.The automotive-grade devices are fully AEC-Q101 qualified and have successfullycompleted extended lifetime testing at 175°Cfor more than 1,600 hours with extremely lowPPM levels.

The full portfolio includes more than 250new parts, in single and dual packages, andwill be released by March 2013. September2012 will see the release of the full LFPAK T6portfolio. LFPAK is NXP’s improved Power-SO8package, which is proven to have superiorelectrical, mechanical and thermal propertiesover the industry’s Power-SO8.

voltage tolerance ensuring that the MOSFETcan be fully controlled at high temperatures.

NXP’s Trench 6 technology also enhancesswitching performance compared to previousgenerations of TrenchMOS. The devices havevery low gate charge for a given on-stateresistance, which maximises the efficiency ofDC/DC switching applications.

As an evolutionary architecture benefitingfrom a proven track record in the standard


FREESCALEAPPLICATIONS

• Automotive instruments• Heating ventilation and air conditioning • Lighting • Doors, window-lift and seat control • DSI airbag system • Central gateway/in-vehicle networking • Body electronics • Hybrid-powertrain electronics • Engine management

FEATURES• Compatible with LIN protocol specification

1.3, 2.0, 2.1, and SAEJ2602-2• Low standby current in sleep mode• Over-temperature protection• Local and remote wake-up capability• 5.0V- and 3.3V-compatible digital inputs




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LIN physical-layer IC cuts emitted noise, increasesnoise immunity

The Freescale MC33662 is a LINPhysical-layer device (PHY) thatfeatures active techniques to minimiseemitted LIN-signal noise throughout thefrequency range. It also incorporatesinnovations that ensure high EMIimmunity and an ability to withstandESD that exceeds AEC-Q, IEC andvehicle-manufacturers’ specifications.

To minimise the emitted noise, the MC33662optimises the signal transition time andslope to actively produce a roundedwaveform at the rising and fallingedges. This reduces emitted noise inthe low-frequency range. In addition,the corner shape of the waveform isoptimised to reduce the energy emittedat higher frequencies.

Improvements in design methodologyhave successfully improved the LIN-signalintegrity margin. As a result, the MC33662ensures total signal integrity throughout the

EMI frequency range from 150kHz to 1GHz.In addition, the MC33662 has been

specifically designed to withstand the mostsevere automotive ESD standards defined atboth the IC and system level. These include:• AEC-Q100 Human Body Model (HBM) up

to 10kV• Machine Model (MM) up to 200V• Charged Device Model (CDM) up to 750V• ISO10605:2008 and IEC61000-4-2:2008• Human Metal Model (HMM) standard

practice• Car-manufacturers’ own ESD requirements.

Three versions are available, providinga choice of 20kbaud operating baud

rate for the MC33662L andMC33662S, or 10kbaud for the

MC33662J. All variantssupport a 100kbaud rate fortest and programmingmodes.

The devices are able tooperate from a wide supply-

voltage range, from 7.0V to 18V, andare designed to remain functional up to 27V

and while withstanding transients during loaddump up to 40V.


Vishay's families of tantalum chip capacitors provide a broadselection of robust, high-performing devices

Vishay’s automotive-grade tantalumproducts family has four series of solidtantalum chip capacitors that arequalified to AEC-Q200, offeringrobustness, reliability and a high levelof efficiency for the harsh environmentof automotive applications. Among otheradvantages are a wide operating-temperature range, low ESR, a rangeof standard capacitance values, androbust moulded surface-mount casesin industry-standard sizes.


The TP3 series is specified for operation from -55°C to 125°C, and has high ripple-currentcapability. Devices are available with voltageratings from 4V to 50V, and standardcapacitance values from 0.1µF to 470µF. Theseries supports EIA case sizes A, B, C, D andE, giving designers a choice of footprintsbetween 3.2mm x 1.6mm and 7.3mm x 4.3mm.

The TH3 series is specified for operation from-55°C to 150°C, and devices are availablewith voltage ratings from 6.3V to 50V.Standard capacitance values from 0.33µF to220µF are available, and the case sizessupported are EIA types A, B, C, D and E.

The TH4 series for high-temperatureapplications is able to operate at up to175°C, and is available in EIA case types B,C and D corresponding to 3.5mm x 2.8mm,6.0mm x 3.2mm and 7.3mm x 4.3mmfootprints. Devices in this series are availablein voltage ratings from 6.3V to 16V.

The TP8 series offers high volumetricefficiency targeted for space-constrainedautomotive applications. It offers theindustry’s highest capacitance-voltageproduct per case size, small sizes including0603 footprint, L-shaped terminations and abroad capacitance range to suit mostautomotive applications.

The TP3, TH3, TH4 and TP8 series havemaximum ESR of 500mΩ, 5Ω or 10Ω, andare available with capacitance tolerance of±10% or ±20%.

VISHAY

APPLICATIONS• Engine controls• Safety systems• Oil-quality sensors• Transmission controls• Body electronics• Tyre-Pressure Monitoring System (TPMS)• Rear-view mirrors• Camera modules• Remote keyless entry

FEATURES• Matte tin, tin/lead or gold case

terminations• 100% surge-current tested• 50% voltage derating at specified

temperature



Rugged Schottky barrier rectifiers combine highcurrent and voltage ratings with low energy losses

APPLICATIONS• Automotive ECUs• Automotive interior lighting• Display panels and user interfaces• Low-voltage power supplies• Industrial power supplies

FEATURES• AEC-Q101 qualified• 1.5A maximum average forward current• Reverse-voltage rating:

• 20V (PMEG2015EPK)• 40V (PMEG4015EPK)

• Forward voltage:• 420mV (PMEG2015EPK)• 610mV (PMEG4015EPK)

• Solderable side pads



With reverse-voltage ratings of 20V or 40V,the devices can be used in the control

of dashboard backlights, LEDinterior lighting and otherautomotive power-supplyapplications. Other power-conversion and conditioningroles for these devices includelow-voltage rectification, high-efficiency DC/DC conversion,switched-mode powersupplies and reverse-polarity

protection.All devices are encapsulated

in the leadless ultra-smallDFN1608D-2 surface-mount

plastic package with visible andsolderable side pads, and are AEC-Q101

qualified.

NXP Semiconductors’PMEG2015EPK andPMEG4015EPK PlanarMaximum-Efficiency General-Application (MEGA) Schottkybarrier rectifiers feature anintegrated guard ring forstress protection, and havehigh forward-current andreverse-voltage ratings withlow energy losses to targeta variety of applications andmarkets including automotiveelectronics.

NXP SEMICONDUCTORS

Automotive-grade solid tantalum chip-capacitor familiesoffer broad choice of AEC-Q200 qualified variants



Second-generation CAN/LIN system-basis chips featureinnovative power-management and fail-safe capabilities

System-basis chips integrate power-management and peripheral functionality

The Freescale MC33903, MC33904and MC33905 are second-generationSystem-Basis Chips (SBCs), whichcombine LIN and CAN functionalityenabling enhancement of moduledesigns.

The latest-generation SBCs actas an advanced power-management unit for the hostmicrocontroller and additionalintegrated circuits such assensors and CAN transceivers.Each device has a built-inenhanced high-speed CANinterface compliant withISO11898-2 and -5, with localand bus-failure diagnostics,integrated protection featuresand fail-safe operation modebased on an innovative state-machine concept.

Power-managementcapabilities of the new SBCsinclude multiple under-voltage

detection functions and address various MCUspecifications and system operating modessuch as cranking. There is also a fullyprotected embedded 5.0V regulator for theCAN driver, as well as advanced diagnosticsand monitoring for SPI, MCU, ECU power-supply and other critical pins.

The three devices create a pin-compatiblefamily giving designers the choice of zero, oneor two LIN 2.1 interfaces with LIN output-pinswitches. The available device variants also

allow designers to utilise up tofour wake-up pins which canalso be reconfigured as outputdrivers, providing addedflexibility. Designers also havethe choice of 3.3V or 5.0Voutputs in each type, allowingdirect connection to a widevariety of microcontroller.

The MC33903, MC33904and MC33905 are supportedby an enablement ecosystemthat includes an evaluationboard, software interface,EMC/ESD-conformancereports and training material toallow faster time to market andsimplified design.

FREESCALE

Low dark-current LDO regulators cut vehicle standbypower for longer battery life

Rohm Semiconductor’s BD7xxL2family of LDO regulators achieves verylow dark current to help minimise drainon a vehicle’s battery when the engineis not running, enabling the battery tomaintain functions such as keylessentry, anti-theft and audio-systemmemory, and ensure reliable restarting.

As the number of microcontrollers used inautomotive systems continues to grow, thereis increasing concern over the current drawnwhen the vehicle is parked or unused for anextended period of time. The usual techniqueto reduce standby current is to increase theimpedance of the regulator’s internal circuit.

However, high impedance causes the circuit tobecome susceptible to noise, makesminiaturisation more difficult, and slows downthe circuit during startup.

Rohm’s BD7xxL2 family overcomes thesechallenges by combining decades of expertisein automotive LDO technologies with aproprietary noise-proof circuit design. Thedevices have a typical dark current of 6.5µA,which is 80% lower than conventional LDOregulators. This effectively reduces battery loadand protects against premature drainage dueto extended periods of non-use. Powerconsumption during normal operation is alsoreduced, conserving total system energy.

Further benefits include the ability to usesmall, low-cost ceramic compensationcapacitors at the output, as well as integratedfeatures such as over-current protection andthermal shutdown.

The family provides two output-voltageoptions. BD733L2 devices have a fixed outputvoltage of 3.3V, while BD750L2 has a 5.0Voutput.

ROHM SEMICONDUCTOR

APPLICATIONS• Lighting controls• Body electronics• Safety and chassis electronics• Powertrain controls• Low-end engine management

FEATURES• Voltage, current and temperature

protection• Extremely low quiescent current in low-

power modes• MUX output pin for internal-signal and

power-supply monitoring (except MC339033.0V and 5.0V MCU supply-voltage devicevariants)

• Debug mode for faster development• Included in Freescale’s product-longevity

programme


APPLICATIONS• Body electronics• Engine ECUs• Security systems• Audio equipment

FEATURES• 50V maximum voltage• ±2% output-voltage accuracy• 200mA output-current capability• Package options:

HTSOP-J8, TO252-3, TO263-3 andSOT223-4




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Part Number Package Type Dimensions

BD7xxL2EFJ HTSOP-J8 4.90mm x 6.00mm x 1.00mm

BD7xxL2FP TO252-3 6.50mm x 9.50mm x 2.50mm

BD7xxL2FP2 TO263-3 10.16mm x 15.10mm x 4.57mm

BD7xxL2FP3 SOT223-4 7.00mm x 6.56mm x 1.60mm

Rugged, sealed connector systemtargets off-highway applications


AMPSEAL 16 connectors withstand the tough demands imposed byindustrial, agricultural and recreational vehicles


The AMPSEAL connector range features asingle-latch design with anti-overstress feature,is sealed to IP67, and is suitable for operationfrom -40°C to 125°C.

The size 16 (1.58mm) pin and socketcontacts are stamped and formed versions ofTE’s screw-machined MIL-C-39029specification contacts. They have a highresistance to vibration, are tested to 35G, andare made from a thick high-performance alloythat provides high resistance to stress and acurrent-carrying capacity of 13A. The terminalaccepts wires with a conductor size of 0.5mm2

to 2.0mm2 and insulation diameter from

1.30mm to 3.67mm.Receptacle and pin housings are available in

2, 3, 4, 6, 8 or 12 positions, and featurekeying as well as polarisation to prevent mis-mating. The housings are of a one-piecedesign with integral connector-positionassurance, which prevents the connector frombeing unintentionally disconnected. Otherfeatures include Primary-Latch Reinforcement(PLR), an integral secondary-locking feature to

prevent terminal back-out, a wire seal, and awire-seal cover. The built-in wire seal andcover also help to reduce handling costs andpart-number inventory. In addition, theconnector body features a mounting-clipattachment which assists secure positioningfor use in high-vibration environments.

TE CONNECTIVITY

24V high-side eXtreme switches integrate advancedcontrol, protection and diagnostics

FREESCALE

APPLICATIONS• Body electronics• Lighting controls• Low-end/high-end control modules

FEATURES• Steady-state current per channel:

3.0A (MC20XS4200)6.0A (MC10XS4200)9.0A (MC06XS4200)

• Separate bulb and DC motor latchedover-current handling

• Sub-10µA sleep mode• Individually programmable internal/external

PWM clock signals• Open-load detection


APPLICATIONS• Diesel-engine electronics• Sensor interconnects• Transmission and joystick controls• Exterior-lighting systems

FEATURES• Resistant to wide range of chemicals• Lanceless contacts• Sealed interface and wires• Integral contact-beam protection• 50-cycles durability• Colour coding




The TE Connectivity™ (TE) AMPSEAL 16™

connector system for use in heavy-dutyapplications such as industrial,agricultural and recreational vehiclescomprises wire-to-wire and wire-to-device connectors with built-in securityand protection features to ensurerugged and reliable connections.

P.I.E.S E C T I O N

The MC06XS4200, MC10XS4200 andMC20XS4200 are 24V dual high-sideeXtreme switches from Freescale thatcombine flexible built-incontrols and a highnumber of protectiveand diagnosticfunctions optimised fortruck, bus, andindustrial applications.

Each switch channel in thedual high-side switches haslow on-state resistance:6mΩ in the MC06XS4200;10mΩ in the MC10XS4200;and 20mΩ in the MC20XS4200. The switchescan be used to control a variety of differentload types such as bulbs, solenoids, or DCmotors. Control, device configuration, anddiagnostics are performed through a 16-bitSPI connection facilitating easy integration intoexisting applications. The devices implementprotection features including over-current,

short-circuit, and over-temperature protection,with programmable auto-retry capability.

Both channels can be controlled individuallyby external or internal clock signals, or bydirect inputs. Using the internal clock allowsfully autonomous device operation. Theoutput-voltage slew rates are individuallyprogrammable, which helps to improve EMC

performance.The devices also provide the

advantage of a dynamic over-currentthreshold profile, which prevents theswitch from shutting off upon inrush,

while retaining theability to closelytrack the loadcurrent. In addition,a programmablesensing ratio allowsindividual sensingof the switchingcurrent in eachchannel. Ifcommunicationwith the external

microcontroller is interrupted, the device entersa fail-safe operation mode, but remainsoperational, controllable and protected.

Board of the Month

Freescale is evolving a new enablementconcept for Kinetis microcontrollers, designedto provide effective and easy-to-use evaluationboards that will help speed up design startsand simplify projects.

The Freedom Board Platform aims toprovide ultra low-cost boards for evaluationand development that are straightforward butuseful, with quick and effective out-of-boxdemo applications.

To help designers to start valuable projecttasks with minimal preparation, the Freedom

boards will prioritise easy access to thetarget microcontroller I/Os, easy exercisingof low-power modes, and easilyaccessible test points for measuring

power consumption. The boards will alsofeature a built-in debug interface for Flash

programming and run control.As the Freedom Board Platform continues

to evolve, Freescale will add more boards,supporting more microcontroller variants. Allboards will follow a standard form factor, andwill support expansion boards to allow designscaling and flexibility.

To celebrate the 100th issue of FTM, Futureis offering 100 FTM readers the chance toreceive one of 100 Freedom boards. To applyfor the Freedom-KL25Z board for the KinetisKL25Z128VLK4 ARM® Cortex™-M0 MCU, visit:my-boardclub.com/ftm.

FreescaleMulti-core processing withFreescale QorIQ P5040General-purpose development platformfor evaluating full features ofP5040/P5021 quad-core processors.Board Reference:P5040QDS-PA Response Number: 13

FreescaleAutomotive MCU design

Evaluation kit containing two LINconnectors and 12V wall-plug connectorfor demonstrating features of FreescaleS12VR64 automotive microcontroller.Board Reference:S12VR64EVB Response Number: 27

Freescale (continued)CAN/LIN System-Basis Chipconfiguration

Evaluation board supportingimplementation of MC33903D3 andMC33903D5 System-Basis Chips (SBCs).Board Reference:KIT33903BD3EVBEKIT33903BD5EVBEKIT33905BD3EVBEKIT33905D5EKEVBEResponse Number: 41

Microchip8-bit PIC® microcontrollerdevelopmentThe PIC12F(HV)752 MCUs are supported byMicrochip’s standard suite of developmenttools, including the PICkit™ 3 developmentkit and the open-sourced MPLAB®X IDEsoftware.Board Reference: PG164130 Response Number: 30

Freescale (continued)Safety-critical automotive design

Motherboard compatible with plug-in minimodules, creating an evaluation systemfor Freescale MPC56xx microcontrollers.Board Reference:XPC56xxMB2 Response Number: 34

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READ THIS TO FIND OUT ABOUT

• MEMS sensor fusion for indoor-navigation capabilities• Calculating errors in dead-reckoning systems• Software- and hardware-based approaches to error compensation

T E C H N I C A L V I E W


Understanding dead reckoning for Dead reckoning has saved many a sailor’s life, but has proveddifficult to implement using modern technology. New MEMS-based accelerometers and gyroscopes have reawakenedinterest in using dead reckoning to allow personal navigationdevices to operate continuously when no GPS signal isavailable, such as in cities, offices, malls or other coveredareas. In this article, Mathias Nygård, FAE, Future Electronics(Sweden), outlines the sources of error and shows howdesigners can minimise the errors attributable to motionsensors.

When calculating geographical position using dead reckoning, thecalculated data inevitably becomes polluted as measurement errorsaccumulate through the duration of the journey. The success of modernnavigation equipment using dead reckoning is ultimately dependent onthe size of the error introduced by the motion-sensing system, themargin for error allowed in the application, and the resources that canbe committed to developing error-compensation systems if necessary.Error compensation, which might use actual location data derived fromGPS-satellite signals, is generally costly to implement.

The position-drift conundrum: a maths problemA typical system architecture for today’s dead-reckoning devices willcombine a MEMS accelerometer and a MEMS gyroscope.

The accelerometer measures the rate of change in speed of amovement, and the gyroscope measures any change in the direction ofthat movement on any one plane: xy, xz or yz. To perform deadreckoning in three dimensions, a multi-axis accelerometer and multi-axisgyroscope may be used. This article describes the design of 2D dead-reckoning systems, but the principles and calculations can be appliedequally to the third dimension of travel.

To appreciate the effect of measurement error on dead reckoning, it ishelpful to understand the maths involved. To calculate the end position,S(t), using dead reckoning from a known start position, a double integralover time must be applied to the accelerometer signal, A(t). This functioncalculates the distance travelled, and inevitably also accumulates andamplifies the error factors.

In the real world, the accelerometer signal, A(t), is composed of twofactors: the true acceleration, a(t), and its associated errors, E(t). Analysisof E(t) provides a view of the errors and noise factors which cause adeviation from the actual position: these are N(t) for acceleration inaccuracy,Q(t) for digitisation noise, and S0 for offset errors such as zero-g factor andtemperature drift. These factors are expressed in the following equations:

It should be noted that the gyroscope data must also be taken intoaccount when calculating system error. However, the error attributable tothe gyroscope is not subject to such accumulation as seen in theaccelerometer data. Only a tolerance figure is included, and no double-integral maths is necessary.

Figure 1 gives the mathematical expression of the accelerometer’soutput. But how can actual figures for acceleration inaccuracy,digitisation noise and offset error be derived? And can these errors beeliminated?

There are two ways of deriving the magnitude of the error: 1) estimationbased on the accelerometer’s datasheet; or 2) actual data drawn fromthe operation of a real system. The first approach can be used beforeimplementation and during the specification phase; the second indicateswhether a prototype or production unit which has already beenimplemented is within its allowed tolerance range.

Method 1, using datasheet information, calls for a formula commonlyused for electronic noise calculations for components such as resistorsand op-amps, as well as sensors. This formula produces the tolerancefor the accelerometer signal before digitisation:

which is equivalent to:

where ODR (Output Data Rate) is divided by two to conform with theNyquist sampling theorem. PDF refers to the datasheet figurerepresenting noise density (µg/vHz).

The datasheet noise-density figure normally offers 95.5% confidencethat any given sensor-signal outcome, before digitisation, lies within arange of two standard deviations from the mean ‘true acceleration value’if calculated with the above formula.

Note that the N(t) sensor error noise term in the S(t) double integral islooked upon as being a white-noise process µ[n], the process beingnormally distributed N(µ, σ2) with a DC term µ and a zero mean unitvariance scaled to have variance σ2.

For illustration, datasheet values for two advanced accelerometers,the MMA8451Q from Freescale and the LIS3DH fromSTMicroelectronics, are shown in Table 1.

Method 2 appears more satisfactory to the design engineer, since thefigure of merit it provides covers the behaviour of the whole signal chain,including the digitisation block and noise contributed by themicrocontroller’s ADC and PLLs (assuming analogue sensors are used).The drawback, however, is that this method can only be usedretrospectively, to check the performance of a system that has alreadybeen built.

This method entails making a statistical estimate of the N(µ, σ2)distribution, as described above, based on sample outcomemeasurements, in order to provide a tolerance for the accelerometersignal chain. This is a straightforward calculation, and the method isoutlined in Freescale Semiconductor Application Note 4075.

S(t) = ∫∫ [ A(t) ] d 2t

S(t) = ∫∫ [ a(t) + E(t) ] d 2t

S(t) = ∫∫ [ a(t) + N(t) + Q(t) + S0 ] d 2t

N(t) = PDF x √ (Sys. Bandwidth)

N

N(t) = PDF x √ (ODR/2)

cost-effective indoor navigation

Fig. 1: How accelerometer error components grow over time

Table 1: Noise specifications for leading accelerometers

T E C H N I C A L V I E W


The important contributor to system error: offset errorHowever it is measured, noise error tends to cancel out across acomplete cycle of accelerating and decelerating movements. On theother hand, the offset factor S0 is a single-sided phenomenon thatoccurs equally during acceleration and deceleration. Hence thisaccumulates throughout the device’s travel.


Accelerometer Freescale Veyron Accelerometer Family MMA8451Q STMicroelectronics Nano Accelerometer LIS3DH

Part status Active ActiveNumber of bits 14-bit 12-bitCounts over total range 16384.000 4096.000Linear acceleration measurement range ±2g (/±4g/±8g) ±2g (/±4g/±8g/±16g)ERROR SECTION [p-p] [RMS Error]^2 [RMS Error]^2

• Sensitivity [typ. mg/digit] 0.244 7.45n 0.977 119.21n• Sensitivity change vs. temperature [%/°C] ±0.008 1.9p ±0.010 47.7p• Typical Zero-g level offset accuracy [mg] ±2 2u ±40 800u• Zero-g level change vs. temperature [mg/°C] delta from 25°C ±0.15 11n ±0.50 125n

Uncalibrated total sum of RMS errors at 1°C deviation from 25°C 1.42mg 28.29mgCalibrated total sum of RMS errors, 25°C 0.09mg 0.35mgNoise amplitude density PSD [µg/√Hz] 126 @ 400Hz ODR 99 @ 400Hz ODR 220 @ 100Hz ODRODR (Output Data Rate) 1.56Hz to 800Hz 1Hz - 5KHzSystem bandwidth [ODR/2] 200 200 50Noise calculations

RMS noise Nrms = noise amplitude density * √(System BW) [mg RMS] 1.78 1.20 1.56N(t) p-p limits ±2*u(t), 95.5% confidence (=2) [mg] ±3.56 ±2.40 ±3.11SNR = 6.02n + 1.76 = 20*Log( Srms/Nrms ) [dB] 57.99 61.41 59.17ENOB estimate based on Nrms = PSD*√ (ODR/2) 9.34 9.91 9.54ENOB from system measurement (includes all noise incl. quantisation) – – –True resolution based on ENOB [mg/LSB] 6.17 4.16 5.38

Double integration compounds this error and can distort the position datawildly if it is not eliminated from the accelerometer signal (see Figure 1).

This is the main reason why accelerometers require calibration, thusminimising offset error in the OEM’s specific application. Sometimesaccelerometers are shipped factory calibrated, but this seldom cures thedrift problem.

Software algorithms compensate for inaccuracyCareful calibration is the most effective means to minimise total systemerror in a dead-reckoning device. But actual results from testingprototypes may show an unacceptably large accumulated drift inposition after a given time. Typically, this requires software algorithms toprovide a clever compensation for the error in the dead reckoningoutput, which is expensive and time-consuming. This approach is onlyeconomically viable for OEMs manufacturing high-volume or high-endproducts.

The cost arises not only in product development, to devise and writethe algorithms, it can also result in a higher bill-of-materials cost for theend product. This is because algorithms for error compensationgenerally rely on comparing dead-reckoning outputs with absoluteposition data derived from a GPS source, and hence also requires theinclusion of a GPS receiver and supporting circuitry.

A discussion of approaches to developing the algorithms themselvesis outside the scope of this article.

A further complication is the need to compensate in the signal chainfor poor factory offset calibration, by applying low-pass filters or movingaverages to correct for errors occurring as signals are transmittedbetween the sensors and a microcontroller. Using a system-on-chipsuch as Freescale´s MMA9550L, which comprises a microcontroller withan embedded MEMS accelerometer section, power management andconnectivity blocks, provides an effective way to eliminate difficulties withsignal-chain design.


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FUTURE TECHNOLOGY MAGAZINE - FTM Board Club · FUTURE TECHNOLOGY MAGAZINE ISSUE 1209 In association with Design Note: page 13 ... GPS receiver, the Open AT application f ram ewok,