| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a single-phase motor driving circuit for achieving a low noise, a low vibration and a low power consumption. <P>SOLUTION: The motor driving circuit supplies a first driving voltage from one end to the other end of a motor coil for a first period, and supplies a second driving voltage from the other end to one end of the motor coil for a second period. A voltage comparing circuit compares a voltage corresponding to a current flowing in the motor coil with a reference voltage for setting a target of the current flowing in the motor coil. A rotation controlling circuit generates a PWM signal having a pulse width controlled based on a comparison output from the voltage comparing circuit, and outputs it to the motor driving circuit. The reference voltage is decreased so as to make the current be zero at a cross point of tails of the first and second periods in which the first and second driving voltages are supplied. <P>COPYRIGHT: (C)2007,JPO&INPIT |
