Differential speed and directional sensor IC offers dual output

April 30, 2014 // By Graham Prophet
ATS605 from Allegro MicroSystems Europe is a dual-output speed and direction sensing IC sensor designed for use in rotational position sensing applications in conjunction with a ferrous gear target. Its design offers very high-speed sensing and switching capability in rotational position sensing.

The ATS605 incorporates three Hall sensing elements which are used to create two independent differential channels. Signals from these channels are then processed by the IC, which contains a digital circuit designed to eliminate the detrimental effects of magnet and system offsets. The differential signals are used to produce a highly accurate speed output and, if desired, provide information on the direction of rotation.

Advanced calibration techniques are used to optimise signal offset and amplitude. This calibration, combined with the digital tracking of the signal, results in accurate switch-points over different air gaps and temperature. The open-drain outputs provide voltage output signals which mirror the sensed target’s shape, with a phase separation between the two channels proportional to the size of the target teeth compared with the Hall element spacing.

Incorporating all the sensing and processing circuitry within a single IC package eases mechanical design and installation and provides the capability to sense small or higher-resolution teeth for added accuracy.

The sensor is optimised for a variety of applications requiring dual-phase gear speed and position signal information or simultaneous high-resolution gear speed and direction information.

It is targeted at the automotive, industrial, white goods and commercial markets for end applications that include industrial motor control in forklift trucks, robotics and rotational gearing, electric motor position controls and sliding-door/long-travel bi-directional sensing.

The ATS605 is available in a 4-lead SIP package (suffix SG). The SG package incorporates a rare-earth pellet for ease of manufacturing, consistent performance over temperature, and enhanced reliability.

Allegro MicroSystems; www.allegromicro.com