METHODS AND APPARATUS FOR ERROR DETECTION IN A MAGNETIC FIELD SENSOR

摘要

A magnetic field sensor for detecting motion of an object includes error detection circuiting and processing. Magnetic field sensing elements are configured to generate at least two magnetic field signals in response to a magnetic field associated with the object which signals are used by detectors to generate right and left channel signals with edges indicative of motion of the object. A direction calculation processor responsive to right and left channel signals generates a direction signal having a state indicative of a direction of motion of the object and an output signal generator generates an output signal having a pulse indicative of the direction of motion of the object in response to the direction signal. An error detection processor responsive to the output signal and to the direction signal is configured to detect an error in at least one of the direction signal and the output signal.

主权项

1. A magnetic field sensor for detecting motion of an object, comprising:
a plurality of magnetic field sensing elements configured to generate at least two magnetic field signals in response to a magnetic field associated with the object; a first detector circuit responsive to at least one of the magnetic field signals and configured to generate a right channel signal having edges indicative of motion of the object; a second detector circuit responsive to at least one of the magnetic field signals and configured to generate a left channel signal having edges indicative of motion of the object; a direction calculation processor responsive to the right and left channel signals to generate a direction signal having a state indicative of a direction of motion of the object; an output signal generator responsive to the direction signal to generate an output signal having a pulse indicative of the direction of motion of the object; and an error detection processor responsive to the output signal and to the direction signal to detect an error in at least one of the direction signal and the output signal.