New Industry Products

Monolithic Hall Position Sensors with Dual-Outputs

March 25, 2019 by Scott McMahan

Melexis announced the MLX90374, the latest addition to its third generation of Triaxis® Hall sensors, and the first from the company to provide multiple outputs from a monolithic device. With dual outputs for the sensed motion, the MLX90374 can eliminate the need for a second position sensor in a range of applications.

The MLX90374 is suitable for automotive applications including inhibitor switches or transmission range selection (TRS) sensing and can also be used in drivetrains or to detect the position of pedals, steering wheel, or seat height.

Based on Melexis' proprietary 3D Hall-sensing technology, the MLX90374 provides the absolute position of a moving magnet, covering linear displacement, and 360° rotation. As a single chip solution, it integrates a magnetic front-end, DSP and ADC, along with a temperature sensor and signal conditioning block for an optional external sensor. (See block diagram above).

The monolithic MLX90374 offers two independently configurable output stages. The primary output can encode position data in either PWM or SENT. The second output offers position data encoded as a 12-bit PWM signal. Optionally, the second output of the MLX90374 ABB can operate as a switch signal with programmable thresholds, while the MLX90374 ABC variant has an additional third output that is also configured as a switch. Each output is powered by the on-chip DSP and takes either the on-chip magnetic data as its source or an external sensor input.

A lower flux density requirement over previous Triaxis® products enables the use smaller and lower cost magnets. The low degradation of less than 0.2% error provides the needed performance, even in high-temperature applications including in the engine bay. An additional stray-field-robust operating mode allows for operation in areas where external stray fields (up to 4kA/m or 5mT) may be present.

Like other members of the third generation Triaxis® family, the MLX90374 offers a programmable measurement range and programmable output characteristics. The SENT (SAE J2716) output is compliant to SENT 2016 and previous versions. It outputs data with the single secure sensor (A.3) or dual throttle position sensor (A.1) format.

"With the introduction of the fourth device in the third generation Triaxis® sensor range, our customers can now make even better use of our advanced 3D Hall sensing technology. The inclusion of a second output has the potential to save significant size, space and power in automotive applications, which will help to continue driving the electrification of automobiles and the move towards greater autonomy," Nick Czarnecki, Global Marketing Manager Position and Speed Sensors, commented.

With ISO 26262 ASIL C (SEooC) readiness, an ambient operating temperature range of -40°C to +160°C and low thermal drift, the MLX90374 is available in a single die PCB-less DMP-4 package or a single die surface mount SOIC-8 package.

Key Features

  • Highly flexible position sensing
    • On-axis rotary
    • Off-axis rotary
    • Linear stroke
  • ASIL-C (SEooC) component
  • Stray field immune (up to 4kA/m) mode of operation
  • In-application programmable
  • Two configurable output drivers supporting
    • 2x PWM
    • 1x SENT or PWM, 1x Switch
    • 1x SENT or PWM, 2x Switch
  • EMC capable to automotive OEM requirements
  • Variety of package types
    • SOIC-8, single die package
    • DMP-4, single die PCB-less package
  • Operating temperature -40°C to 160°C