High Linearity, Low Drift Hall Sensor IC for Automotive Torque-Sensing Applications

Published  April 2, 2020   0
MLX91377 Hall Sensor IC

Melexis has introduced the ASIL-ready MLX91377 Hall sensor IC that can operate at ambient temperature up to 160°C and suitable for safety-critical automotive systems such as electric power-assisted steering (EPAS). By combining high linearity with excellent thermal stability, including low offset and sensitivity drift the MLX91377 supports accurate, dependable torque sensing in EPAS systems to enable safe control in conventional and autonomous driving.

The MLX91377 offers more flexibility to the designers with its programmable measurement range and multi-point calibration, and the variety of output protocols enables one IC to be used in multiple applications reducing qualification efforts and costs. The Short PWM Code (SPC) protocol permits measurements to be taken and transmitted upon detection of a trigger pulse. The user can synchronize up to four 2kHZ MLX91377 sensors for simultaneous magnetic measurements with deterministic latency to ensure high accuracy. The low-noise and high refresh rate allow high control-loop speeds, enabling systems to deliver fast response times with minimal filtering.

The MLX91377 can be used in a wide variety of automotive and industrial contactless position-sensing use cases, including steering torque sensors, acceleration, brake, or clutch pedal sensors, absolute linear position sensors, float-level sensors, non-contacting potentiometers, small-angle position sensors, and small stroke position sensors.

The MLX91377 developed as a Safety Element Out of Context (SEooC) and complies with ISO 26262 standard, it is also qualified to AEC Q-100 Grade 0. The MLX91377 offers a high level of functional safety, per die, and can detect internal failures and enter a safe state to prevent unintended vehicle behavior as it supports functional safety level ASIL-C in digital (SENT or SPC) mode and ASIL-B in analog mode. The availability of the device in a TSSOP-16 package further expands this by offering two fully redundant dies to enable support for safety-critical applications like steering and braking systems.