Patent ID: 7274161

Claim:
A motor driving apparatus that drives a motor having plural-phase windings and a rotor, the motor apparatus comprising: a position detecting means for detecting position of said rotor according to a comparison signal obtained by comparing terminal voltages of said windings in a non-activation phase with a center tap voltage of a common potential of said plural-phase windings and outputting a position detection signal; a state determining means for detecting the state of said rotor, and outputting the result obtained by comparing the position detection signal with a predetermined value; an activation controlling means for performing activation control of said windings by setting a leading phase of an activation control signal with respect to said position detection signal when said state determining means outputs a first output signal, and performing activation control of said windings by canceling leading the leading phase of an activation control signal with respect to said position detection signal when said state determining means outputs a second output signal; and a switching controlling means for outputting a drive signal for performing high-frequency switching control according to a command signal to said activation controlling means.