Patent ID: 6777926
Filing Date: 2004-08-17
Classification: G01P

Abstract:
A method for sensing the speed and/or direction of a rotating target, said method comprising the steps of:locating a first differential Hall package opposite to a second differential Hall package to provide symmetrical stability for accurate phasing thereof, wherein said first differential Hall package and second differential Hall package comprise mirror images of one another; generating a first output signal by said first differential Hall package and a second output signal by said second differential Hall package during a rotation of a rotating target; comparing said first Hall output signal to said second Hall output signal during a shift of said rotating target from a sinusoidal phase to a non-sinusoidal phase thereof, thereby permitting accurate phase information indicative of the speed and direction of said rotating target to be obtained; and analyzing particular target features associated with a phase of said rotating target, wherein said particular target features are wide with respect to an associated target-to-sensing plane and a sensing plane-to-magnet distance.