MOTOR DRIVING DEVICE FOR ADJUSTING MOTOR SPEED AND SETTING THE LOWEST ROTATING SPEED AND THE DRIVING METHOD THEREOF

摘要

A motor driving device and a driving method thereof is disclosed herein and comprises a PWM converting circuit, an oscillator, a comparator, a controlling unit. The PWM converting circuit converts an analog signal according to an adjustable the highest setting voltage, an adjustable the lowest setting voltage and a controlling signal. The analog signal and a triangular signal generated by the oscillator are inputted to the comparator to compare to output a drive signal to the controlling unit so as to control the motor speed. The motor driving device in the present invention can adjust the motor rotating speed curve to set the lowest rotating speed of the motor so as to achieve the function of changing the motor rotating speed and maintain the lowest torque of the motor to increase the flexibility of the motor speed control.