Apple Inc.
Haptic engine having a single sensing magnet and multiple hall-effect sensors

Abstract:

A haptic engine for measuring displacement of the haptic engine's mass uses a single sensing magnet that is carried by the mass along a driving direction. The haptic engine further uses two or more Hall-effect sensors, which are spaced apart (i) from each other along a direction parallel to the driving direction and (ii) from the single sensing magnet along a direction orthogonal to the driving direction, and are disposed adjacent to an ASIC that receives the sensors' output.