| 摘要 |
PROBLEM TO BE SOLVED: To provide a rotation angle detector for reducing the detection errors of rotation angle, and preventing detected errors of the rotation angle from increasing, in particular, after product shipment. SOLUTION: Two Hall elements outputs sinusoidal output signals with a phase difference that is varied, in response to changes in magnetic field due to the rotation of an object to be detected. An ECU implements an offset correction (S114) and an amplitude correction (S116) to the output signals from two Hall elements. When one of two output signals from the two Hall elements is "0" (S118), the phase difference between the output signals from two Hall elements is calculated from the magnitude of the other output signal from two Hall elements by calculations involving trigonometric function. The phase difference, used in detecting the rotation angle of the object to be detected, is updated by the calculated phase difference (S120). The ECU detects the rotation angle of the object to be detected, based on the phase difference between the output signals (S122). COPYRIGHT: (C)2008,JPO&INPIT
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