Advanced position sensing - Vogel · 2017. 10. 21. · Confidential © ams AG 2014 Page 3. Our focus. High performance analog ICs. Target markets

Confidential © ams AG 2014

Oliver WeberMarketing & Business Development SSI Asia

Advanced position sensing for EPS and other motor controlled applications

December 2014

本文档来自2014国际汽车技术年会未经允许不得转载

Confidential © ams AG 2014Page 2

At a glance• Focus on high performance analog semiconductors• Sensor solutions, sensor interfaces, power management, wireless• Ultra-low power, highest accuracy, sensitivity and integration• Analog IDM: world class design + in-house manufacturing

By the numbers• Over 30 years of design experience• Revenues 2013 € 378m ($ 502m)• More than 1,400 employees worldwide • Over 7,800 customers worldwide

ams overview



Our focus

High performance analog ICs

Target markets Consumer and Communications Automotive, Industrial & Medical

Core expertise Sensor and sensorinterfaces

Powermanagement Wireless

Shaping the world with sensor solutions.



Sensors which measure angular or linear position• Contacting: through a mechanical connection• Non-contacting: without physical contact

Non-contacting position sensors are• more reliable• offer a longer functional life due to the absence of mechanical

parts and physical contact

Strong market-trend to move from simple angle and distance sensors towards robust, intelligent sensor systems and applications with multiple simultaneous measurement axes.

ams focuses on non-contacting, hall-based and intelligent Position Sensors

What are position sensors?



• Emergence of contactless and integrated magnetic position sensors

• Traditional sensors are replaced by contactless sensors that handle complex and highly integrated electronics – delivering higher sensitivity, smaller form factors and increased flexibility

• Strong trend from simple angle and distance sensors towards robust, intelligent sensor systems and applications with multiple simultaneous measurement axes

• Tackling the shortcomings of optical, magneto resistive, inductive and linear Hall sensors and switches

• Longest lifetime, insensitive to humidity, dust, dirt and harsh environments

• Solutions offer enhanced precision, repeatability, and robustness andstray field immunity.

Why hall-based magnetic position sensing?



Hall-effect magnetic position sensors

3D positionAngle position Linear position



Measure the linear part of the magnetic fieldMagnetic field basics

Measured magnetic field

NS



ams patented technology is using 4 Hall sensorsPlacing the magnet above the sensor area



ams patented principleImmune to external magnetic stray fields

H2H4 Hall

0

[V] Volts

12

3

4

Vdi

ff 1

Vdi

ff 2

external magnetic stray field

Vdiff 1 = Vdiff 2



vertical magnetic field Bz

characteristics

=

)cos(*ˆ)sin(*ˆ

arctanα

αα

a

a)tan(

)cos(*ˆ)sin(*ˆ

αα

α=

aa

How does it work?Hall-based magnetic position sensing



The need for Contactless Technologies• Magnetic sensors are replacing other types of sensors i.e. inductive

sensors, optical sensors, potentiometer technology, increased need for precision & safety (i.e. ISO26262)

Improvements in Reliability & Precision• Powertrain hybridization, more electronics in the car, the need for higher

reliability in transmission applications, higher precision in powertrain applications e. g. start/stop systems

Lower CO2 emissions requirements • Better sensor performance & higher resolution, steering applications with

reduced standby current and a smart “measurement on demand” Cost reduction

• Sensors with new digital interfaces i.e. SENT replace sensors with traditional analog output, enhanced robustness/diagnostic, cost reductions for the entire signal chain

Increased use of brush-less (BLDC) motors• Major advantages of brushless DC motors include higher efficiency at

converting electricity into mechanical power, reduced noise, longer lifetime and higher reliability.“

Trends in the automotive market



Selected position sensor applications

Exhaust gas recirculation sensor (EGR)

Electronic Power Steering (EPS)

Gearbox / Gear shifter

SteeringColumn

Automatic-manual (AMT) / Dual-clutch transmission (DCT)

Throttle

Pedals

Chassis level



• Steering system ECUs are growing faster than any other vehicle Domain – 15% CAAGR global 2007-2017

• Electric Power Steering dominates the steering market• EPS outperforms other markets in growth

EPS covers all car segments



2014• 99% of the EPS Motors are using brush• Mainly resolvers used for motor control

2015-2016 Trends• Strong trend to replace brushed motors with brushless motors• Adding magnetic position sensors for motor commutation & motor control

Strong growth for highly accurate magnetic position sensing demand ahead!

EPS in China



• Magnetic position sensing is becoming the leading solution for automobile EPS systems

• Sophisticated sensor devices with multiple sensing elements on a single die enable faster and more accurate acquisition of information.

• Precise position of the automobile's steering wheel, improved performance of its EPS system while keeping costs and required space to a minimum.

- Stability over temperature- Robustness against tolerances- Robustness against interfering field- Up to 7 pole pairs- Up to 14.500 rpm (depending on

application)- Angle error <1° deg- ISO26262-compliance

Integrated position sensing in EPS

BLDC

Rotor Position Sensor

Electric Power Steering leads the steering market, EPS outperforms other markets in growth.

The motor position sensor controls the

commutation of a brushless DC motor

employed in the system.



AS5235

• Resolution: 10.5-bit • Maximum speed: 12000rpm• Low system propagation delay: 20µs• rms output noise: 0.15degree• SPI interface with in-system programming• Integrated turns counter: 12-bit• Current consumption

• Normal Operating Mode: 17mA• Low Power Mode*: 6mA• Sleep Mode**: 50µA

• Input Magnetic field Bz: 20 – 90 mT• Wide temperature range -40 – 150°C• Dual-die

SAS + MC single on-axis position sensor (embedded)

**100ms polling time* 100% duty cycle with reduces noise performance



ams’ stacked die solutionMaximum safety

Schematic concept



New series of magnetic position sensors ideally suited to all motor control and angle measurement applications

• AS5147 - automotive applications • AS5147P – for rotation speeds up to 28.000rpm• AS5247 - functional safety compliance

DAEC™ (Dynamic Angle Error Compensation)• Eliminating the measurement errors as a result of

propagation delays. • Extremely accurate angle measurements of rotors

spinning at high speed• Specified with a maximum ±0.17° angle error at

14,500rpm (excluding INL and noise)

Of course, with complete stray field immunity • Proven differential sensing technique - like all ams

magnetic position sensors• Enables the devices to be used in electrically noisy

environments without need for shielding.

The new generation position sensors - enabling best in class accuracy at high rotation speedsAS5x47 series



System propagation delayCausing a “natural” angle error

tdelay = 40-100µs

Position Sensor



Dynamic angle errorSpeed dependent angle error

Speed: 10 RPMDAE = 0,012°

Speed: 1.000 RPMDAE = 1,20°Speed: 10.000 RPMDAE = 12,0°

100µs

0.02.04.06.08.0

10.012.014.016.018.020.0

- 5,000 10,000 15,000

Dynamic Angle Error [deg]

Angle Error [deg]



Integrated dynamic angle error compensation – patent registeredDAEC™ - Revolutionary

Dynamic Angle Error

Hardware Compensation integrated!No Software needed – a perfect solution for EPS Motor Control

External HW + SW compensation needed

Mag

netic

Pos

ition

Sen

sor S

yste

m



Commitment to Quality & Safety

Zero-defect philosophy & culture

• AEC-Q100 automotive qualification, "Safe Launch Program“, "Burn-In" and "Three-Temperature" testing procedure

Functional Safety is an integral part of ams’ IC Design & Development process

• Diagnosis IP, ISO conformant development, 200mm in-house wafer fab, ISO-TS16949

• Very low defect density, ID for every automotive IC, in-house ESD/EMC lab

Adhering to latest Quality/Safety Standards i.e. ISO26262

• ISO26262 - track-record for cost effective implementation, development flow conformant, safety manager for ISO26262 projects

• Close collaboration between IC developer and user at FMEDA, considering all diagnosis functions, IC-internal and host system

Hall-based Magnetic Position Sensing



Launch next generation products• Coming soon AS560X series - potentiometer replacement• Coming soon: AS54XX series – long stroke linear position sensing

New product development and continuous improvements• Performance (higher accuracy), interfaces (SENT, PSI5), package

(PCB-less)

Products that deliver increased safety and reliability • ISO26262, automotive qualification, short lead times

Enabling low-cost and smaller magnets• Magnetic input field … 5mT

Providing smaller magnets and lower assembly tolerances• Integral Non-Linearity ... ±0.42°

Products that accelerate and simplify the design process• Simplify products and tools – application support

Where We Are Going…


Confidential © ams AG 2013

Thank you

Please visit our website www.ams.com


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Advanced position sensing - Vogel · 2017. 10. 21. · Confidential © ams AG 2014 Page 3. Our focus. High performance analog ICs. Target markets