Allegro claims first high-resolution GMR sensor for ADAS

Allegro MicroSystems, Inc. has introduced its A19360 wheel speed and distance sensor for emerging applications in advanced driver assistance systems (ADAS). Designed for SAE J3016 levels 3 (conditional automation), 4 (high automation), and 5 (full automation), the giant magnetoresistance (GMR) sensor provides the signal resolution and reliability required for advanced levels of automation in passenger vehicles and mobility-as-a-service applications, said Allegro.

Click for a larger image. (Source: Allegro MicroSystems)

Claiming the A19360 as the first high-resolution GMR sensor for ADAS, Allegro calls the A19360 “a game changer for automakers working on autonomous vehicles” that “require superior wheel rotation information for accurate low-speed control.” In addition to supporting higher levels of automation, the GMR sensor enables features such as park assist, fully autonomous valet parking and traffic jam assistance with reportedly 4× better positional measurement.

“The A19360 provides high-resolution information to automotive systems by generating extra output events per magnetic cycle with a special protocol that’s compatible with electronic control units (ECUs),” said the company.

Available in two-resolution options per cycle, the 8-event-per-magnetic-cycle mode provides an increment for every ~5 mm of tire roll and a 4-event-per-magnetic-cycle mode that doubles the number of outputs per magnetic cycle (compared to a normal wheel speed sensor). These features enable designers to cut the number of poles on in-wheel ring magnets in half, either saving costs or increasing the air gap and still achieve the same number of increments per revolution, said Allegro.

Allegro A19360 GMR sensor block diagram. (Source: Allegro MicroSystems)

The A19360 was developed for ISO 26262 ASIL B(D), and is built on Allegro’s monolithic GMR technology with ultra-low jitter and large air gap capabilities. The A19360 is available in a 2-pin SIP package (suffix UB) that is lead (Pb) free, with tin lead frame plating.