Patent ID: 6523271
Filing Date: 2003-02-25
Classification: G01C

Abstract:
A method of adjusting drive current of a magnetism sensor which is a method of adjusting drive current of a magnetism sensor of a magnetism detecting circuit in which sensor driving means having a drive current source capable of supplying drive current adjustable in a range of N steps, respectively drives an X-axis magnetism sensor and a Y-axis magnetism sensor in a bridge constitution by drive current having a magnitude in correspondence with drive current set values stored to drive current set value storing means, said method of adjusting drive current of a magnetism sensor is characterized in comprising the following steps of:(1) a step of respectively measuring bridge resistance of the X-axis magnetism sensor and bridge resistance of the Y-axis magnetism sensor; (2) a step of respectively calculating the drive current set value of the X-axis magnetism sensor and the drive current set value of the Y-axis magnetism sensor from measured values of the bridge resistance of the X-axis magnetism sensor and the bridge resistance of the Y-axis magnetism sensor: and (3) a step of respectively storing the drive current set value of the X-axis magnetism sensor and the drive current set value of the Y-axis magnetism sensor to the drive current storing means.