Sensor Introduction
The CT815x and CT81xx sensor family from Allegro MicroSystems is built on XtremeSense™ TMR technology and includes models for unipolar, bipolar, omnipolar, and analog magnetic position detection. Designed for ultra-low power and high sensitivity, this family supports contactless, reliable motion detection suitable for battery-operated, space-constrained applications.
Demo Setup Overview
The lab setup includes a stepper motor with magnetic coupler and five integrated TMR sensors mounted in alignment with the rotating field. The sensors are observed during controlled bidirectional linear or rotary motion, enabling validation of their response characteristics.
Target Applications
The TMR Position Sensor Evaluation Lab enables users to interact with the sensors in a real-time, programmable test environment. Through the LiveBench interface, users can initiate and control linear motion using a stepper motor mechanism. This includes setting the direction of motion and specifying the number of motor steps to precisely determine the extent of displacement. As the magnet moves relative to the mounted sensors, users can observe and evaluate the sensor outputs in real time.
Both analog voltage signals (from CT8150 and CT8152) and digital logic transitions (from CT8111, CT8122, and CT8132) are streamed live, allowing users to monitor how each sensor responds to changes in magnetic field due to motion. The system supports comparative analysis, enabling validation of switching thresholds, latching behavior, and analog linearity.
Additionally, the lab platform supports exporting of data—captured signals and sensor readings can be saved for offline processing, documentation, or integration into reports and design evaluations. This interactive, data-driven approach accelerates understanding of sensor performance and helps validate application-specific use cases efficiently.
The lab setup offers a well-integrated evaluation platform equipped with essential features for studying TMR-based magnetic sensing. At its core, a magnetic feedback system uses a combination of high-strength Neodymium (NdFeB) and Ferrite magnets to generate a stable and consistent magnetic field. This ensures uniformity across all sensor types and enhances the reliability of each test case.
A stepper motor-driven linear stage precisely controls the bidirectional movement of a magnet relative to the sensors. This allows for comprehensive analysis of sensor response during forward and reverse motions and supports both incremental and continuous displacement modes.
Digital logic behavior—such as the threshold-based switching of the CT8111, the latching of the CT8122, and the omnipolar response of the CT8132—is easily observed in real time. The LiveBench interface provides users with instant feedback on output transitions, enabling close inspection of hysteresis behavior and switching accuracy.
Analog output from the CT8150 and CT8152 sensors is monitored through a built-in oscilloscope in the remote lab. This view allows detailed observation of signal amplitude and waveform shape in response to magnetic field variations, aiding in the assessment of linearity, resolution, and noise performance.
All five sensors are arranged in a synchronized layout, ensuring they are subjected to identical motion and magnetic conditions. This coordinated measurement environment simplifies direct performance comparisons, making it easier for users to determine the best-fit sensor for their specific application.