| 摘要 |
PURPOSE:To eliminate overshooting and decrease setting time, by a method wherein control input and bias voltage are added, thereby a PWM signal is generated. CONSTITUTION:A PWM signal generator 11 comprises part 11-2 to input a control input Vc, part 11-3 to input a bias voltage Vx, and part 11-1 to add the control input Vc and the bias voltage Vx and to generate PWM signal. The PWM signal is inputted to an amplifier 13. A signal processing circuit 12 outputs signal to change current flowing through a coil of a brushless DC motor based on output of a position detector mounted on the brushless DC motor, and output of the signal processing circuit 12 together with the PWM signal is amplified by the amplifier 13. |
