TDK launches 2D Hall-effect sensors with ASIL certification

TDK Corporation introduces the stray-field robust Micronas HAL/HAR 35xy* 2D Hall-effect position sensor family for automotive and industrial applications. Building on the success of the HAL/HAR 39xy series, the new sensors offer enhanced features and capabilities to meet the growing demand for stray-field robust 2D position detection in linear and angular applications. While the HAL/HAR 39xy family focuses on high flexibility, diverse features and interfaces, and superior performance, HAL/HAR 35xy is designed for mainstream applications that demand a core feature set with reduced flexibility, while maintaining high standards in functional safety and performance. With versatile programming, high accuracy, and ISO 26262 compliance, the HAL/HAR 35xy is a potential solution for safety-critical automotive applications, including accelerator pedals, brake pedal position or brake stroke sensors, steering angle detection, valve position such as throttle, shift position, non-contact potentiometers, transmission position detection, and chassis height measurement.** Start of production is planned for June 2025. Samples are already available.

The first sensors in the new family comprise the HAL 3550, a single-die version, and the HAR 3550, a dual-die version that provides full redundancy with two independent dies housed in a single package. The new sensor family is designed to cater to the stringent functional safety requirements of ISO 26262-compliant development. HAL 3550 and HAR 3550 are defined as safety elements out of context (SEooC) and are ASIL C ready, making them suitable for integration into automotive safety-related systems up to ASIL D.

HAL 3550 and HAR 3550 are high-resolution position sensors engineered for precise position measurements, featuring a linear, ratiometric analog output with passive wire-break detection, as well as configurable PWM or SENT outputs. The SENT mode supports messages with or without pause pulse, adhering to SAE J2716 rev. 4 standards, with customizable parameters such as tick time and frame format. The PWM output offers flexibility with frequencies ranging from 0.1 kHz to 2 kHz. In addition, HAL/HAR 3550 offers a switch output (open-drain), derived from calculated position information or other sources along the signal path, such as temperature or magnetic-field amplitude. Users can define on/off switching points, switch logic, and polarity to suit their specific application needs.

Capable of measuring a full 360° angular range and linear movements of a magnet, the sensors are particularly suited for chassis position sensor applications, featuring a modulo function that allows the 360° measurement range to be divided into sub-segments of 90°, 120°, or 180°.

Utilizing Hall technology, the HAL/HAR 3550 measures vertical and horizontal magnetic-field components and effectively suppresses external magnetic stray fields with an array of Hall plates. A simple, low-cost two-pole ferrite magnet is sufficient for rotation angle measurements, ideally positioned in an end-of-shaft configuration. The sensors also support stray-field robust off-axis measurements.

On-chip signal processing capabilities allow the calculation of one angle per die from the magnetic-field components. This information is then converted into an analog or digital output signal. Key characteristics such as gain, offset, and reference position can be tailored to the magnetic circuitry via programmable non-volatile memory.

Designed for both automotive and industrial applications, the sensors operate within an ambient temperature range of –40 °C to 150 °C. They are available in a SOIC8 SMD package for the single-die version and a TSSOP16 SMD package for the dual-die version.