| 摘要 |
<P>PROBLEM TO BE SOLVED: To drive a single-phase brushless motor without using any position detection element such as hall element to reduce the size and the cost of the motor. <P>SOLUTION: The single-phase brushless motor includes: a drive signal generation circuit that generates a drive signal for alternately supplying a first drive current and a second drive current including therebetween a non-conducting period when any of the first drive current and the second drive current flowing in an opposite direction to the drive current of the first drive current is not supplied to the drive coil of the single-phase brushless motor; an output circuit that supplies the first drive current or the second drive current to the drive coil responding to the drive signal; and a zero cross detecting circuit that detects a zero cross of an induced voltage which is generated on the drive coil during a non-conducting period. The drive signal generation circuit determines the length of the next conducting period on the basis of the driving period from the start of the conducting period that the output circuit supplies the first or second drive current to the drive coil to a point when the zero cross detecting circuit detects the zero cross. <P>COPYRIGHT: (C)2013,JPO&INPIT |
