The A1642 is an optimized Hall-effect sensing integrated circuit that provides a user-friendly solution for true zero-speed digital ring-magnet sensing in two-wire applications. This small package can be assembled simply and used in conjunction with a wide variety of target shapes and sizes.
The integrated circuit incorporates a dual-element Hall effect sensor and signal processing that switches in response to differential magnetic signals created by ring magnet poles. The circuitry contains a sophisticated digital circuit to reduce system offsets, to calibrate the gain for air-gap–independent switchpoints, and to achieve true zero-speed operation. Signal optimization occurs at power-on through the combination of offset and gain adjust and is maintained throughout the operating time with the use of a running-mode calibration. The running-mode calibration allows immunity to environmental effects such as micro-oscillations of the target or sudden air gap changes.
The regulated current output is configured for two-wire applications and the sensor IC is ideally suited for obtaining speed and duty cycle information in ABS (anti-lock braking systems). The 1.5 mm spacing between the dual Hall elements is optimized for fine pitch ring-magnet-based configurations. For applications requiring sensing of rotating ferrous gears and targets, refer to the ATS642LSH series of products. The package is lead (Pb) free, with 100% matte tin leadframe plating.