The magnetoresistance (GMR) sensor provides automakers with the signal resolution and reliability required for advanced levels of automation in passenger vehicles and mobility-as-a-service applications.
According to a recent report by consulting firm strategy, the first passenger vehicles with level 3 (conditional automation) capabilities should be generally available by the end of 2022, and level 4 (high automation) capabilities available in people-mover applications by 2025. As a consequence, automakers are actively developing software and hardware systems and need components - such as the A19360 - that can enable those systems.
The A19360 sensor has been designed for SAE J3016 levels of automation 3, 4 and 5, and is intended to safely enable features such as park assist, fully autonomous valet parking and traffic jam assistance, according to the company.
Automated and autonomous vehicles require wheel rotation information for accurate low-speed control and the A19360 has been developed to provide 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).
The sensor includes an 8-event-per-magnetic-cycle mode targeted at ADAS applications, providing an increment for every ~5 mm of tire roll. It also includes a 4-event-per-magnetic-cycle mode that doubles the number of outputs per magnetic cycle (compared to a normal wheel speed sensor). This allows designers to halve the number of poles on in-wheel ring magnets to save costs, or increase the air gap and still obtain the same number of increments per revolution.
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 company’s SolidSpeed Digital Architecture provides the widest dynamic range of operating air gap and highly adaptive performance that eliminates flatlining due to thermal drift and system dynamics.
The A19360 is available in a 2-pin SIP package (suffix UB) that is lead (Pb) free, with tin lead frame plating. The UB package includes an IC and protection capacitor integrated into a single over-moulded package, with an additional moulded lead-stabilising bar for robust shipping and ease of assembly.