HAL/HAR 35xy* is an ASIL Class C stray-field robust Hall-effect 2D position sensor family with enhanced features for safety-critical automotive applications

The new sensors include single-chip versions (HAL 3550) and dual-chip versions (HAR 3550) with analog (linear, ratio) and digital (PWM, SENT, and switch) output interfaces

This range is based on the flagship Micronas HAL/HAR 39xy offering a more cost-effective option without sacrificing performance or functional safety

Key target application scenarios include steering wheel Angle, brake and accelerator pedal position, valve position, and chassis position detection **

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 sensor family offers 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 series focuses on high flexibility, diverse features and interfaces, and superior performance, the HAL/HAR 35xy is designed for mainstream applications that require a core set of features with reduced flexibility but still high standards in functional safety and performance. HAL/HAR 35xy can be programmed in a variety of ways, with high accuracy and in accordance with ISO 26262 standards. It is a potential solution for automotive safety-critical applications including gas pedal, brake pedal position or brake stroke sensors, steering Angle detection, throttle and other valve positions, shift positions, non-contact potentiometers, transmission position detection and chassis height measurement. ** Production is scheduled for June 2025. Samples are available now.

The first products in the new sensor family include the single-chip version of HAL 3550 and the dual-chip version of HAR 3550, which integrates two separate chips in a single package for full redundancy. The new sensor family is designed to meet the stringent functional safety requirements of ISO 26262 compliant development. HAL 3550 and HAR 3550 have been defined as ASIL Class C out-of-context Independent Safety Units (SEooC) for integration into automotive safety-related systems at the highest ASIL Class D.

The HAL 3550 and HAR 3550 are high-resolution position sensors designed for accurate position measurement with linear ratio analog outputs and passive break detection while supporting configurable PWM or SENT outputs. The SENT mode supports messages with or without pause pulses and complies with SAE J2716 Edition 4 with customizable parameters such as time indication and frame format. The PWM output has a frequency range of 0.1 kHz to 2 kHz, providing flexibility. In addition, the HAL/HAR 3550 provides a switching output (open drain) derived from calculated position data or other sources along the device's signal path, such as temperature or magnetic field amplitude. Users can define on/off switch points, switching logic, and polarity to meet their specific application scenario needs.

These sensors are capable of measuring the full 360° angular range and linear motion of the magnet, especially suitable for chassis position sensor applications, and have a modal function that divides the 360° measurement range into 90°, 120° or 180° sub-segments.

HAL/HAR 3550 utilizes Hall technology to measure vertical and horizontal magnetic field components and uses Hall plate arrays to suppress external stray magnetic fields. A simple, low-cost, bipolar ferrite magnet is sufficient for rotation Angle measurements and can ideally be placed in a shaft-end configuration. The sensor also supports robust off-axis measurement of stray fields.

On-chip signal processing can calculate the Angle of each chip based on the magnetic field component. This information is then converted into an analog or digital output signal. Key characteristics such as gain, offset and reference position can be adjusted for the magnetic circuit with programmable non-volatile memory.

These sensors are designed for automotive and industrial applications and operate in ambient temperatures ranging from -40 ° C to 150 ° C. The single-chip version uses SOIC8 SMD package, and the dual-chip version uses TSSOP16 SMD package.

Main application **

● Gas pedal

● Brake pedal position/brake stroke sensor

● Steering Angle

● Valve position, such as throttle

● Shift position

● Non-contact potentiometer

● Transmission position detection

● Chassis height

Main features and benefits ***

● Accurate Angle measurement with a range of up to 360° and linear position detection

● Stray field compensation

● SEooC ASIL Class C, compliant with ISO 26262, supports functional safety application scenarios

● Wide supply voltage range: 4V to up to 18V

● Overvoltage and reverse voltage protection

● Undervoltage and overvoltage protection

Customer configurable analog (12-bit ratio), PWM or SENT outputs, or included switched outputs (open drain) and customer configurable switching levels

● Operating temperature range between -40℃ and 150℃

● Programming via the output pin of the sensor. No additional programming pins required

A variety of configurable signal processing parameters, such as output gain and offset, reference position, temperature-dependent offset, etc.

Model number

encapsulation

Output format

Angle error

Field amplitude range

Safety problem

HAL 3550

SOIC8

Analog, SENT, PWM and Switch

+ / - 0.9 °

10 mT …  200 mT

ASIL C ready, developed according to ISO 26262:2018

HAR 3550

TSSOP16