Allegro introduces new Hall Effect speed and direction sensors

     Allegro MicroSystems introduces a new Hall effect speed and direction sensor IC with hysteresis detection. The A1232 is an ultra-sensitive temperature-stabilized magnetic induction device that is ideal for ring-shaped speed and direction sensing systems in harsh automotive and industrial applications.

     The A1232 is the first of its kind and has the ability to detect when it is in the hysteresis band when powered on. This function reduces the angular accuracy error caused by missing edges when starting. This new magnetic sensor IC is targeted at the automotive motor market. Main applications include: window lifters, sunroofs, sliding doors and backup/hatchback doors. The new device is also suitable for applications such as garage door openers and shutters.

     Allegro's A1232 is equipped with dual Hall elements with a pitch of 1.63 mm and uses lithographic calibration technology with an error range of 1 µm. The precise spacing of sensing elements eliminates the major manufacturing difficulties associated with the use of fine-spaced toroidal magnets. The output signal of the dual Hall element is encoded to realize the logical output and provide the speed and direction data of the target. Factory trim and Allegro's proprietary chopper stabilization/dynamic offset cancellation technology enable precise, symmetrical magnetic switching points for a wide range of operating conditions.

     With a built-in voltage regulator, short circuit protection output, internal Zener diode clamp, battery reverse protection, and an operating range of -40°C to + 150°C, the A1232 fully meets the stringent requirements for robustness in automotive applications.