High-Precision Angle Sensing with the Infineon TLE5009 GMR-Based Sensor

In the rapidly advancing fields of automotive, industrial automation, and robotics, the demand for highly accurate and reliable angular position sensing has never been greater. Meeting this challenge, Infineon Technologies has developed the TLE5009, a groundbreaking sensor that leverages the principles of Giant Magneto Resistance (GMR) to deliver exceptional performance in even the most demanding environments.

Unlike traditional sensing technologies such as Hall effect or inductive sensors, GMR technology is based on a quantum mechanical effect observed in thin-film layered structures. These structures exhibit a significant change in electrical resistance when exposed to an external magnetic field. This inherent characteristic makes GMR sensors incredibly sensitive to magnetic field direction, which is the fundamental requirement for precise angle measurement. The TLE5009 harnesses this physics, integrating a GMR element on a single silicon chip alongside the necessary signal processing circuitry.

The core functionality of the TLE5009 involves measuring the orientation of a magnetic field generated by a simple two-pole magnet that is mounted on the rotating shaft whose position is to be measured. As the magnet rotates, the direction of its magnetic field changes. The integrated GMR bridge detects these minute changes in the planar magnetic field direction. The raw analog signals are then processed by an advanced on-chip signal conditioning system. This includes amplification, temperature compensation, and dynamic offset cancellation, which are critical for maintaining accuracy across the entire operating temperature range (-40 °C to 150 °C) and over the product's lifetime.

A key differentiator of the TLE5009 is its output. It provides two simultaneous and independent output interfaces: a Pulse Width Modulation (PWM) signal and a Short-Wire Protocol (SWP) digital interface (SENT protocol optional). This dual-output capability offers designers maximum flexibility, allowing the same sensor to interface with different microcontroller units (MCUs) without additional components. The PWM output provides an analog-like representation of the angle, while the digital SWP output offers robust, noise-immune communication.

The performance specifications of the TLE5009 are what truly set it apart. It achieves an industry-leading accuracy of better than ±0.5° at room temperature over a full 360° rotation. Furthermore, it maintains this high precision at high speeds and is capable of measuring angles in static (0 RPM) and dynamic (up to 40,000 RPM) conditions with equal fidelity. Its robust design ensures superior reliability against external stray fields, mechanical stress, and ESD events, making it a perfect fit for safety-critical applications like electric power steering (EPS), throttle control, and brake pedals.

ICGOO

The Infineon TLE5009 GMR sensor represents a significant leap forward in angle sensing technology. By masterfully integrating the sensitive GMR effect with sophisticated on-chip processing and dual output options, it delivers unmatched precision, robustness, and flexibility. It is an enabling technology for systems that demand the highest levels of performance and safety, solidifying its position as a premier choice for engineers designing the next generation of automotive and industrial systems.

Keywords:

GMR-Based Sensor

High-Precision Angle Sensing

On-Chip Signal Conditioning

PWM and SWP Output

Superior Reliability