AllegroMicro launches new speed sensor IC

Allegro Microsystems has released the A17301, a new Hall effect sensor IC intended for two-wheeled vehicles, particularly in position and timing applications like speedometers and tachometers for engine control.

Integrating electromagnetic capability (EMC) components into a small SIP package, the A17301 is a robust solution for digital ring-magnet sensing or ferromagnetic target sensing when coupled with a back-biasing magnet. This device has been designed to eliminate the need for external filter capacitors while improving reliability and reducing the cost of a final sensor assembly. The IC incorporates dual Hall-effect elements with 2.2 mm spacing and signal processing that switches in response to differential magnetic signals.

The A17301 contains sophisticated digital circuits to reduce system offsets, to calibrate the gain for airgap independent switch points, and to achieve true zero-speed operation. Running mode recalibration provides immunity to environmental effects such as micro-oscillations of the target or sudden air gap changes. The use of a digital peak detector for output switching control ensures that the input signal is continuously and accurately tracked, regardless of the amount of signal shift between output edges.

The A17301 is available in a 3-pin SIP (suffix UC). The package is lead (Pb) free with 100% matt-tin lead frame plating and an operating ambient temperature range of -40°C to 160°C.

Author
Neil Tyler