Patent ID: 7567078

Claim:
A magnetic rotation-angle sensor comprising: a magnetic-pole generation means for generating one or more pairs of N-polarity and S-polarity magnetic poles; a plurality of magnetic sensors, arranged around the magnetic-pole generation means, with a predetermined angle to a rotation center of the magnetic-pole generation means; a plurality of polarity determination means for determining polarities of sensor output signals outputted from the magnetic sensors and outputting polarity determination signals indicating the determined polarities; a plurality of absolute-value generation means for generating absolute values corresponding to the sensor output signals outputted from the magnetic sensors; a plurality of comparison-result output means for comparing the generated absolute values and outputting absolute value comparison signals indicating results of the comparison; an angle determination means for determining rotation angle of the magnetic-pole generation means, based on the polarity determination signals and the absolute value comparison signals, and outputting a predetermined determination result signal; and an addition means for adding at least two sensor output signals outputted from the magnetic sensors and then generating a third sensor output signal, wherein the third sensor output signal is inputted to at least one each of the plurality of polarity determination means and the plurality of absolute-value generation means to output polarity determination signals and absolute-value-comparison signals that correspond to the third sensor output signal, and the angle determination means determines the rotation angle of the magnetic-pole generation means based on the polarity determination signals and the absolute-value-comparison signals to output a predetermined determination result signal.