Automotive-qualified 6-axis inertial measurement unit for navigation & telematics

October 31, 2014 // By Graham Prophet
STMicroelectronics says it has the smallest integrated 6-axis Inertial Measurement Unit; based on its own THELMA technology that integrates both acceleration and angular-rate sensors onto the same silicon, it incorporates perfect data synchronisation between the sensor outputs.

The 6-axis IMU, with AEC-Q100 qualification for automotive applications, features low-noise and improved output resolution. The tiny ASM330LXH IMU is suitable for in-dash car-navigation solutions that require accurate and reliable inertial sensors to optimise positioning and direction, even in the absence of a strong GNSS (Global Navigation Satellite System) signal.

Multi-axis gyroscopes and accelerometers, such as the ASM330LXH, empower Dead Reckoning software algorithms that calculate current position from a previously determined location updated by time, acceleration, and change of direction. The new device also targets on-board units for electronic road tolling and other vehicle telematics systems.

Built on ST's own fab, on its 200-mm manufacturing line using the proprietary THELMA (Thick-Epi-PolyLayer for Microgyroscopes and Accelerometers) micromachining process technology that enables the integration on the same silicon of both a 3-axis acceleration and 3-axis angular-rate sensor (gyroscope), the ASM330LXH IMU is mounted in a 3 x 3 x 1.1 mm Land Grid Array package.

The device offers selectable full-scale ranges of 2/4/8/16g and 125/245/500/1000/2000dps with 16-bit synchronised data outputs, at six user-selectable output data rates, for both the gyroscope and accelerometer. An SPI digital output allows the trouble-free transport of sensor data to the microcontroller, and I²C is also supported. Energy efficiency is assured via power-down, low-power, and normal power modes.

AEC-Q100 qualified for automotive non-safety applications, the ASM330LXH is a robust sensor [up to 10000g shock survivability] that operates over an extended industrial temperature range (-40°C to +85°C). The device will cost $6 (1000).