Allegro AxMR Platform Integrates Magnetoresistive Sensors & Precision BiCMOS

April 10, 2018 by Paul Shepard

Allegro MicroSystems announced the launch of its new AxMR™ technology platform. AxMR™ integrates high sensitivity MR (magnetoresistive) sensor elements and high precision BiCMOS circuits on a single silicon integrated circuit.

The launch is the culmination of more than five years of extensive research and development efforts, a sizable investment that supports Allegro’s mission to create a broad portfolio of innovative magnetic sensor ICs for high growth applications within the automotive and industrial markets.

The commitment to develop this platform has been augmented with a substantial investment in high precision thin film deposition tools and equipment within an advanced BCD wafer manufacturing facility, where high-volume manufacturing is under way.

“Through integration Allegro is able to combine our automotive grade, high-voltage wafer processes with high accuracy, automotive grade MR sensors.  The result is a family of high reliability, innovative, small form factor, monolithic ICs that easily fit into industry standard IC packages,” said Michael Doogue, Vice President of Business Development.

Allegro's AGMR™ technology was designed to withstand the rigorous automotive under hood environment.  AGMR™ technology is thermally stable to greater than 150°C, even in the presence of large magnetic fields. This platform sets the stage for Allegro to expand its product offerings in speed, electrical current, and angle sensing applications.

“Hall-effect technology meets the needs of many applications in Allegro’s target markets, but there are certain applications, particularly in the areas of ADAS and high efficiency vehicles, where xMR™ technology offers more elegant solutions relative to Hall technology,” Doogue added. “In these applications, Allegro’s xMR™ ICs provide more accurate measurement data, enable more favorable mechanical placement of a sensor IC within a mechanical system, or create smaller form factor solutions with a lower overall cost.”

Allegro's first generation AxMR™ ring-magnet Speed Sensor ICs are already in production at a leading Tier 1 automotive supplier of wheel speed sensors.  These ICs rely on Allegro's patented signal processing algorithms to meet the needs of both standard and direction detection wheel speed sensor platforms.  GMR technology enables low jitter rotational speed measurements that are not possible with Hall effect ICs.

Allegro is actively developing monolithic back-biased GMR sensors for advanced engine management and transmission gear speed sensing applications, where the same low jitter measurements and large air gap performance are essential for advanced powertrain system operation.

Allegro also recently released its first GMR based current sensor IC, a device capable of resolving currents of less than 1mA, and has plans to leverage MR technology to further disrupt the market for monolithic current sensor ICs.