MEMS sensors for automotive applications

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APPLICATIONS

STMicroelectronics is one of the leading automotive electronics suppliers, with tens of years of expertise in manufacturing and testing of ICs designed to perform under the most stringent automotive environmental conditions. We are committed to making cars safer and more comfortable, to improve the life of millions of people every day.

ST has shipped more than 9 billion MEMS sensors to customers and has a unique sensor portfolio, from discrete to fully-integrated solutions. Dedicated 8-inch wafer production lines with high-volume manufacturing and full in-house dual sourcing guarantee fast time-to-market, cost-effectiveness and 100% security of supply.

MEMS sensors are acquiring a key role in automotive infotainment and safety applications. According to IHS*, the market for automotive MEMS devices increased 13% last year, indicating sensor penetration rates that continue to grow faster than the growth of passenger vehicles.

Higher accuracy, self-test capabilities and the need for rapid data transmission are fueling the trend towards more intelligent sensors. ST’s sensors meet these requirements, featuring high resolution, embedded self-test, small size and smart power management to reduce energy consumption.

*Source: IHS Market Tracker Automotive MEMS H1 2014

ST’s automotive solutions

ST’S MARKET-PROVEN MANUFACTURING

TECHNOLOGY

PARTNERSHIP WITH OEMS IN PRODUCT

DEVELOPMENT

HIGH-VOLUME MANUFACTURING

CAPABILITY

EXPERTISE IN MULTI-AXIS

SENSOR INTEGRATION PASSIVE SAFETY

IN DEVELOPMENT

NON-SAFETY

Navigation assistance

Telematics boxes

Infotainment

Anti-theft systems

Airbags-central unit

Airbags-peripherals

Electronic stability control

Electronic stability control

Engine control

Roll detection

Airbags-peripherals

Airbags-peripherals

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Automotive MEMS sensors Non-safety applicationsST offers a portfolio of MEMS automotive sensors qualified according to AEC-Q100. Our automotive sensor portfolio includes digital accelerometers with low- and high-g, full scale, digital 3-axis gyroscopes, and 6-axis system-in-packages (3D digital accelerometer + 3D digital gyroscope).

Low-g 3-axis accelerometers have advanced power-saving features and an extended temperature range that make them the ideal choice for non-critical automotive applications including telematics, navigation, infotainment and security. Our high-g acceleration sensors feature an extended temperature range and are suitable for airbag applications in vehicle safety restraint systems.

Our 3-axis gyroscopes offer superior stability over time and temperature, and guarantee the level of accuracy required by the most advanced navigation systems embedding dead reckoning. Our angular rate sensors for navigation are based on a single sensing structure for motion measurement along all three orthogonal axes, while other solutions on the market rely on two or three independent structures. Our solution eliminates any interference between the axes that inherently degrades the output signal. The result is increased accuracy and reliability of motion-controlled functionalities.

iNEMO® 6-axis system-in-packages integrate accelerometer and gyroscope in a single device, with benefits in terms of accuracy, space and cost optimization. Multi-axis gyroscopes and accelerometers are used for assisted navigation and empower sophisticated dead reckoning software algorithms that calculate current position from a previously determined location updated by time, acceleration, and change of direction.

ST products are developed together with OEMs to the highest possible requirements. Other than sensors already available in the market, ST works with the leading car manufacturers on new sensing solutions for automotive applications.

AIS328DQ ULTRA-LOW-POWER 3-AXIS ACCELEROMETERThe AIS328DQ 3-axis linear accelerometer features ultra-low-power operational modes that allow advanced power-saving and smart sleep-to-wakeup functions. It has dynamic user-selectable full-scales of ±2g/±4g/±8g and is capable of measuring accelerations with output data rates from 0.5 Hz to 1 kHz.

The self-test capability lets the user check the functioning of the sensor in the final application. Available in a small QFPN package with a 4x4 mm footprint, the AIS328DQ is guaranteed to operate over a temperature range from -40 °C to +105 °C.

PASSIVE SAFETY

*Development

NON-SAFETY

• Navigation assistance

• Anti-theft systems

• Telematics boxes

• Infotainment

• AIRBAGS: peripheral and on-board accelerometers

AIS1200PS accelerometerAIS2120SX* accelerometer

AIS328DQ accelerometerA3G4250D GyroAIS3624DQ accelerometerASM330LXH* 6-axis Combo

Key features Benefits

Low power consumption Battery saving (ignition off)

3-axis For accurate tilt measurement

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A3G4250D 3-AXIS DIGITAL GYROSCOPEThe A3G4250D is a low-power 3-axis angular rate sensor able to provide unprecedented stability at zero rate level and sensitivity over temperature and time. It offers ±245 dps full scale and is capable of measuring rates with a user-selectable bandwidth.

Available in a plastic land grid array (LGA) package, it can operate within a temperature range of -40 °C +85 °C.

AIS3624DQ 3-AXIS MEDIUM-G ACCELEROMETER The AIS3624DQ offers the same features of AIS328DQ, including smart power management and small footprint, while offering a more extended full scale range of ±6g/±12g/±24g.

The product addresses a variety of automotive non-safety applications such as eCall systems, telematics boxes, impact recognition and logging systems.

ASM330LXH iNEMO INERTIAL MODULE (3D ACCELEROMETER AND 3D GYROSCOPE)The ASM330LXH is a system-in-package featuring both a 3D digital accelerometer and a 3D digital gyroscope. It has a user-selectable full scale acceleration range of ±2/±4/±8/±16 g and an angular rate range of ±125/±245/±500/±1000/±2000 dps. The ASM330LXH has two operating modes enabling the accelerometer and gyroscope sensors to be either activated at the same ODR or the accelerometer can be enabled while the gyroscope is powered down.

Key features Benefits

3-axis Single device for multiple application (Pitch, Roll, Yaw)

16-bit data output Suitable for high resolution applications

Key features Benefits

Medium-g detection Accurate crash recording

Pin-to-pin compatible with AIS328DQ Scalable solution

Key features Benefits

Single-chip solution Cost-effective

6-axis Independent on tilt installation

Smallest footprint Compact system design

Synchronized output Precise motion reconstruction (by algorithm)

Low power consumption Battery saving (ignition off)

AIS3624DQ is ideal for applications such as eCall systems.

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TESEO-DRAW - SENSOR-ASSISTED NAVIGATION ST provides a fully configurable solution for dead reckoning built with Teseo receivers and sensors, to support different applications.

TESEO-DRAW (Dead Reckoning Automotive Way) optimally merges the contribution from GNSS and sensors:

• Updates car position/velocity when GNSS satellites signal is not available (tunnels, obscured areas)

• Improves car position/velocity when GNSS satellites signals are marginal (urban canyons, partially obscured areas)

The Teseo platform is a high-sensitivity, standalone GPS solution compatible with multiple satellite navigation systems, including the Chinese BeiDou, US GPS, European Galileo, Russian GLONASS and Japanese QZSS.

TeseoDRAW

Poor GNSS

GNSS

No GNSS

GNSS

Position, velocity Position, velocity

Good GNSS

GNSS

Position, velocity

Calibration

Tunnel Open sky Urbancanyon

Multi-layerstreet

Multi-layerparking

ST’S DEAD RECKONING ARCHITECTURESTMicroelectronics has a deep expertise in sensor integration and new application development and can assist customers in their design-in process. ST’s evaluation kits and firmware allows a real-time evaluation of sensors performance in customer’s applications.

Sensor data

CAN BUS (ABS, SPEED,

ESP GYRO)

CLASSIC FREEMOUNT - 3AX GYRO + ODO + ACCELEROMETER

CLASSIC - 1AX GYRO + ODO

CAN BASED - STABILITY GYRO + ODO- DWP FRONT OR REAR

ACCELEROMETER[3AX]

GYRO [1 or 3 AX]

ANALOG ODOMETER

TEMPERATURE SENSOR

GNSS HW

DR CONFIG

DR SENSORS

height (h)

AIS1200PS MEMS SATELLITE ACCELEROMETER SENSOR, SINGLE AXIS WITH PSI5 POINT-TO-POINT INTERFACEThe AIS1200PS is a peripheral acceleration sensor with a single-axis sensing element and an IC interface able to provide acceleration information to a master control unit through a Manchester-coded protocol (125 Kbit/s).

The AIS1200PS has a full scale of ±200 g.

The device is available in a plastic SOIC package with 150 mils reverse frame forming for EMC enhancement and is specified for a temperature range extending from -40 to +125 °C.

Key features Benefits

200 g full scale Wide signal amplitude detection

Temperature range up to 125°C Ideal for harsh environment

Only two external components required Cost-effective

Passive safety applications

Passive safety includes all applications that protect car occupants during a crash and feature post-crash effects mitigation.The airbag control unit (ACU) detects and evaluates a crash, before triggering the appropriate restraint system according to the type of collision and its severity. Information is supplied to the control unit by several satellite acceleration sensors (to evaluate and compare each of their signals).

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AISx120SX SINGLE OR DUAL AXIS CENTRAL ACCELEROMETER

The AIS1120SX / AIS2120SX is a central acceleration sensor with a single- or dual-axis sensing element and an IC interface able to provide the acceleration information to an airbag master control unit via the SPI protocol.

The AIS1120SX / AIS2120SX has a full scale of ±120 g. Available in a plastic SOIC8 package, it is specified for an extended temperature range from -40°C to +105°C.

PRODUCTS UNDER DEVELOPMENTST is developing and qualifying new sensors addressing various automotive applications, with the goal to improve car performance, safety, and comfort:

Key features Benefits

Single- or dual-axis Design flexibility/scalability

Embedded offset cancellation Stability over time

Bandwidth up to 1600 Hz Fast signal response

Design supportWith an extensive expertise in sensor integration and the development of new applications, ST can assist customers in their design-in phase. ST’s evaluation kits and firmware allows a real-time evaluation of sensor performance in customer applications.

Test points

STEVAL-MKI109V2

STM32microcontroller

USB connector

JTAG/SWD

Adapter

ST offers a complete evaluation solution including:

• A full set of DIL24 MEMS non-safety sensor adapters supporting fast prototyping

• eMotion motherboard compatible with all adapters and based on an STM32 microcontroller

• UNICO graphic user interface for direct and real-time access to the sensor outputs and configuration registers.

Board Description Order code

Motherboard

ST MEMS motherboard is based on the high-performance STM32F103 32-bit ARM Cortex™-M3 MCU

Interfaces: USB connector and JTAG/SWD for debugging

DFU-compatible for USB microprocessor firmware updates

Compatible with all ST MEMS adapters

STEVAL-MKI109V2

Adapter board AIS328DQ STEVAL-MKI110V1

Adapter board AIS3624DQ STEVAL-MKI158V1

Adapter board A3G4250D STEVAL-MKI125V1

Adapter board ASM330LXH STEVAL-MKI171V1*

Note: *available starting from H2 2015

• Barometric pressure sensors (starting from 2017) for non-safety applications, such as engine control, mass air flow, seat comfort, and car navigation

• Inertial measurement units (starting from 2018) for active safety applications, such as electronic stability control, roll over stability, hill-start assist, and electronic parking brake

Technical documents

To see all technical documents and files for a specific product, go to www.st.com/sensors and select the product you are interested in through our product catalog. Each part number has a corresponding web page where you can easily find all associated technical documents and resources.

Developer links

• For more information about MEMS sensors for automotive applications: www.st.com/memsauto

• For more information about MEMS evaluation boards: www.st.com/mems-boards

• To take part to our forums: www.st.com/e2e

Online support

For technical support or questions about product availability, pricing, where-to-buy, or other related issues, go to www.st.com/onlinesupport

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All other names are the property of their respective owners

For more information on ST products and solutions, visit www.st.comOrder code: BRMEMSAUTO0515