| 摘要 |
PROBLEM TO BE SOLVED: To provide an angle detector that has high accuracy and high reliability, and is easily miniaturized. SOLUTION: A relative rotation angle with respect to the magnetic field of a Hall element is determined using a vector expressed by outputs from at least one pair of Hall elements 11 and 12 arranged mutually orthogonally. Drive directions of the Hall elements 11 and 12 are changed at predefined frequencies and two pairs of outputs of the Hall elements 11 and 12 are changed and fetched at the predefined frequencies by a switching means. Also, signs of fetched signals are inverted at the predefined frequencies and a pair of Hall element output signals are acquired. The acquired signals areΔΣ-modulated byΔΣmodulators 50 and 60, and angle data are fetched from which various offsets are removed from theΔΣ-modulated signals through a phase synchronizing circuit 200. COPYRIGHT: (C)2010,JPO&INPIT
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