3D magnetic sensor measures rotation and translation in many ways

Called A31315, it includes configurable signal processing, linearisation and angle calculation allows it to resolve the
absolute rotary or linear position of a moving magnetic target.

It has “excellent native angle error over temperature in any plane: <1.2° over -40°C to +150°C,” according to the company.

It is aimed at vehicle driver assistance and autonomous driving systems and comes in a single die version (SOIC-8 package) or a dual die version (TSSOP-14 package) where the die are stacked and accurately aligned for dual-redundancy high reliability use.

“Following safety element out of context [SEooC] functional safety guidelines, A31315 sensor supports ASIL-B (single die) and ASIL-D (dual die) system-level integration in accordance with ISO 26262 and is automotive qualified to AEC-Q100 Grade 0,” said Allegro. “Unlike traditional side-by-side dual die configurations, Allegro’s stacked die construction closely aligns the sensing elements of both die, ensuring the measurement of nearly identical magnetic fields.”

While the integrated circuits can sense in 3D using temperature-compensated vertical and planar Hall-effect elements, parts are always factory programmed to output less than three axis

“The A31315 features ratiometric analog, PWM, or SENT [SAE J2716] interface options to output the angle between the two factory-selected axes [see table below] or the field from a single axis,” said the company. “In addition, the SENT interface provides the option to output the field measurement from both channels.”

On-chip EEPROM with 100 write cycle durability is integrated for programming of configuration and calibration parameters, and includes 92 bits for customer device identification purposes.

Steering, braking, transmission and throttle applications are also foreseen, as well as use in industrial, portable and consumer markets.