| 摘要 |
<P>PROBLEM TO BE SOLVED: To increase torque and increase the number of revolutions by removing such trouble that a current flowing to a coil becomes large enough at the time near the middle of the cycle of the switching of a Hall element, and it becomes large only at the last stage of the period by setting forward the phase of the output signal of the Hall element with a phase circuit, quickening the time when the output voltage of a differential amplifier crosses a reference voltage, and setting forward the time when a transistor is turned on. <P>SOLUTION: This DC motor driving circuit is equipped with a Hall element which outputs two different signals different in phases geared to the rotational position of a rotor, and a drive IC 12 which has a pair of differential input terminals and controls current application to coils 14 and 15 based on the output signal of the Hall element. This is provided with a phase advancing circuit which sets forward the phase of one output signal of the Hall element 11, and supplies the other output signal of the Hall element 11 and the output signal of the phase advancing circuit to the differential input terminal of the drive IC so as to quicken the current application time to the coils 14 and 15. <P>COPYRIGHT: (C)2004,JPO |
