Speed sensor IC suited for two-wheeled vehicles
The release of the new A17301, a new Hall effect sensor IC suitable for two-wheeled vehicles, particularly in position and timing applications like speedometers and tachometers for engine control, has been announced by Allegro Microsystems Europe. 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 new device eliminates 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 2.2mm spacing and signal processing that switches in response to differential magnetic signals.
“The A17301 uses Allegro’s differential architecture, which inherently avoids the flatline and chatter issues that single Hall element solutions often face,” explained Bob Fortin, Vice President of Allegro’s Sensor Business Unit. “This part is ideal for obtaining speed and duty cycle information for position and timing applications.”
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.
Allegro’s 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 to 160°C.