Magnetic Position Sensors
Smarter sensing for motion, angle and linear position.
Allegro’s position sensors deliver accurate, contactless linear and rotary measurements across harsh automotive and industrial environments. With support for multiple output protocols, these sensors simplify design, reduce system complexity, and enable advanced diagnostics in safety-critical applications.
Browse by category
Linear Hall Sensors (1D)
Our linear position sensors deliver high-accuracy one dimensional (1D) position sensing with advanced linearization and strong immunity to air gap variations.
Motor Position Sensors (2D)
Allegro’s 2D angle sensors deliver analog and ultra-low latency (~10 µs) digital outputs for precise motor control in automotive, industrial and robotics applications.
Multi-Axis Linear and Angle Sensors (3D)
Unlock greater mechanical design flexibility and precision with Allegro’s 3DMAG™ multi-axis sensors engineered to capture complex linear and angular motion.
Documentation & Resources
Blog
Precision in Motion: Advanced Sensing for Industrial Control
Explore how the world of industrial automation, precision and reliability are not just goals; they are absolute necessities. Whether it's a multi-axis robotic arm, a smart valve, or a complex human-machine interface (HMI), the ability to accurately and dependably track motion and position is critical.
Application Note
Achieving Fast SENT Message Response with A1346 Linear Hall-Effect Sensor ICs on Shared Bus
AN296131 - In safety-critical magnetic sensing applications, such as torque sensing in electronic power steering (EPS) modules, redundant sensors are often the approach used to achieve desired performance while maintaining strict safety requirements.
Application Note
Signal Path Delay for A31315 3D Sensor
AN296263 - The delay in a signal path can be described as the trail between the real-time angle and the displayed output angle. This delay represents the time needed to convert the magnetic field data sensed by the Hall plates into angle information.
Application Note
Giant Magnetoresistance versus Hall-effect: A Comparison of Technologies for Speed Sensor Applications
Allegro MicroSystems giant magnetoresistance (GMR) effect technology offerings build on lessons learned from experience with Hall-effect devices to enable new options for speed sensing system design.
Application Note
Two-Point-Programming for the A1330
AN296199 - This application note serves as a guide for using a two-point programming algorithm to calculate and program the values needed for short-stroke rotational position sensing with the A1330 angle sensor IC.
Application Note
Effect of Ring Magnet Dimensions on Differential Speed Sensor Performance
AN296251 - In this application note, we describe how ring magnet dimensions affect speed sensor performance is given.
Brochure
3DMAG Position Sensors
Combining our proven planar and vertical Hall technologies, 3DMAG solutions offer robust, high-performing, three-axis magnetic field measurements in a single IC.
Application Note
3D Hall-Effect Sensor Magnetic Tamper Detection Smart Home Systems
AN296223 - The experiment results highlight several advantages of 3D Hall-effect sensors such as their ability to detect strong magnetic fields that are randomly applied to the outside of a smart home device.
Brochure
Brochure: Driving Change by Advancing Personal Mobility Through Cutting-Edge Technology
Our advanced sensor and power IC solutions are engineered specifically to meet the unique requirements of these designs, providing superior performance and reliability in harsh environments and under complex operating conditions.
Technical Article
The Future of Automotive Wheel Sensing with GMR
P0083 - With the rise of vehicle electrification, computerized control systems, and subsystem reliability monitoring, it has become essential for systems to have accurate rotational information for each wheel of the vehicle.
Application Note
Using the SENT Communications Output Protocol with A1341 and A1343 Devices
AN296108 - This application note provides a description of the Allegro implementation of the SENT protocol, which includes extensions developed by Allegro to enhance the information carrying dimensions of the output from the Allegro sensor IC to the vehicle electronic control units (ECU).
Application Note
PCB Ground Plane Optimization for Coreless Current Sensor Applications
AN296277 - This application note provides guidelines on how a PCB ground plane around the sensor location should be designed to achieve optimum performances.
Application Note
Differential Hall-Effect Sensors: Safer and More Reliable for Two-Wheelers of the Future
AN296173 - The use of electronic controls for engine, transmission, and wheel speed in two- and three-wheeled vehicles is growing, particularly in developing nations. This trend is largely driven by mandates to improve air quality, fuel efficiency, and vehicle safety worldwide.
Video
Circular Vertical Hall Sensor IC Technology Overview
Allegro’s family of contactless Hall magnetic high resolution 360° angle sensor ICs are designed for safety critical automotive and industrial applications. With their system-on-chip (SoC) architectures, they provide fast output refresh rates and low signal path latency.
Application Note
Chopper-Stabilized Amplifiers With Track-and-Hold Signal Demodulator
The conventional signal demodulator of a chopper amplifier can be substituted by track-and-hold (T/H) and averaging functions. This arrangement provides offset cancellation without requiring low-pass filters and can ignore the residual offset generated by input spikes.
Application Note
Bipolar Switch Hall-Effect ICs
Bipolar sensor ICs are designed to be sensitive switches. (Note that the term "bipolar" refers to magnetic polarities, and is not related to bipolar semiconductor chip structures.) Hall measurement, bipolar switching, hall switch.
Application Note
Vehicle Safety Systems
Occupant safety is one of the most critical elements of the automobile design. As a result, safety systems continue to become more sophisticated in order to limit, and ultimately prevent, personal injury in the case of an accident.
Application Note
Slide By Sensing for Long Stroke applications using Allegro Angle Sensors
This application note is a guide through the design process for using angle sensor ICs for linear position sensing, including magnet choice and orientation, output linearization, and using sensor IC arrays for extending the measurement range.
Application Note
Unipolar Hall-Effect Sensor IC Basics
There are four general categories of Hall-effect IC devices that provide a digital output: unipolar switches, bipolar switches, omnipolar switches, and latches. Unipolar switches are described in this application note.
Application Note
Omnipolar Switch Hall-Effect IC Basics
There are four general categories of Hall-effect IC devices that provide a digital output: unipolar switches, bipolar switches, omnipolar switches, and latches. Omnipolar switches are described in this application note.
Application Note
Fuel Level Sensor Using Hall-Effect Sensor ICs
AN296152 - Hall-based fuel level sensor ICs are developed to provide high reliability and accurate fuel level sensing for automotive applications. The application of linear and angle sensor ICs for coil-based and digital cluster indicators is presented in this application note.
Application Note
Low-Power and Turns-Count Sensing with the A1337 Angle Sensor IC
AN296116 - This application note covers the use of the Allegro A1337 angle sensor IC for battery powered applications (automotive or non-automotive) that require the sensor to operate in multiple mission modes.
Application Note
Advanced Programming with ASEK DLLs Harmonic Linearization
This application note describes the functions and the process flow the customer can use if the Allegro-provided software is not flexible enough or if custom software is to be used.
Application Note
Micro-Power Position Sensing in Cell Phone Applications
This note will show how to use the Allegro™ A1171 in a standard flip or slide phone, as well as techniques for sensing three positions using only one magnet and one Hall device in a multipurpose application.
Application Note
Using the A1330 in a Short Stroke Application
AN296163 - This application note is a guide for using the A1330 angle
sensor IC for short stroke rotational position sensing, including
information on magnet choice and orientation.