Integrated GMR based Wheel Speed Sensor for Automotive Applications

In this paper we present a novel wheel speed sensor using integrated GMR (Giant Magneto Resistor) technology for automotive applications. Speed sensors are widely used in modern cars especially for safety applications as ABS (anti-locking system) and ESC (electronic stability control) to monitor the speed of each individual wheel. Increasing demand for larger air-gaps and better noise performance (lower jitter) requires sensor principles with higher sensitivity, compared for example to the currently used Hall sensors. The monolithic integration of GMR resistors as sensing elements, together with advanced signal conditioning electronics, provide a smart sensor solution which meets the automotive industry's high reliability requirements with superior performance.