A119x Switches

By Allegro MicroSystems, LLC 234

A119x Switches

Allegro's A119x family of two-wire, unipolar, Hall effect switches can be trimmed by the user at end-of-line to optimize magnetic switchpoint accuracy in the application. These devices are produced on the Allegro advanced BiCMOS wafer fabrication process, which implements a patented high frequency, 4-phase, chopper-stabilization technique. This technique achieves magnetic stability over the full operating temperature range, and eliminates offsets inherent in devices with a single Hall element that are exposed to harsh application environments.

The A119x family has a number of automotive applications. These include sensing seat track position, seat belt buckle presence, hood/trunk latching, and shift selector position.

  • High speed, 4-phase chopper stabilization
    • Low switchpoint drift throughout temperature range
    • Low sensitivity to thermal and mechanical stresses
  • On-chip protection
    • Supply transient protection
    • Reverse battery protection
  • Solid-state reliability
  • On-board voltage regulator
    • 3.0 to 24 V operation
  • Robust EMC and ESD performance
  • Field programmable for optimized switchpoints
  • Industry leading ISO 7637-2 performance through use of proprietary, 40 V clamping structure