| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a position detecting device and a position detecting method canceling an error due to looseness in a vertical direction by eliminating variation in temperature characteristics. <P>SOLUTION: Assuming that a Hall voltage Vhe1 of a Hall element (22a) becomes A*K*Bhe1 (A is the amplification factor of a preamplifier (32), K is a constant, and Bhe1 is the magnetic flux density which the Hall element receives), then a PI regulator (41) automatically changes the bias point of the PI output by feedback control in such a manner that A*K*Bhe1+Vref=AGND (=0) holds. The Hall voltage Vhe2 of the Hall element after amplification becomes A*K*Bhe2. Since K=-Vref/A*Bhe1, the Hall voltage Vhe2 of the Hall element is given by -Vref*Bhe2/Bhe1. Since the Hall voltage is proportional to the magnetic flux density, the expression is equivalent to do division of the output voltages of the hole element (22a) and the Hall element (22b). <P>COPYRIGHT: (C)2013,JPO&INPIT |
