Hall-Effect Sensor Responds to Gear Teeth Signals December 2004 Issue Published Date: January 06, 2005
A single-chip solution that integrates three highly sensitive Hall elements—a samarium cobalt magnet, a pole piece and a Hall-effect IC—the ATS65OLSH is intended for digital gear-tooth sensing and true zero-speed direction/detection in 2-wire applications. The device switches in response to magnetic signals created by ferrous gear teeth. The circuitry contains a sophisticated digital circuit to minimize the effects of magnet and system offsets to achieve true zero-speed operation. The sensor provides a single output that contains both speed and direction information. A user is able to perform diagnostics on the sensor through a digital output protocol that delivers air gap and temperature information. An on-chip voltage regulator permits operation directly off an automobile’s battery. Automotive applications are in anti-lock braking systems (ABS) and vehicle transmissions. Price is $5.19 each/1,000. For further information and availability, call ALLEGRO MICROSYSTEMS, INC., Worcester, MA. (508) 853-5000.
