Abstract: A fan rotary speed controlling device includes a first signal generating circuit, a second signal generating circuit, a pulse width modulation (PWM) circuit and a switching circuit. The first signal generating circuit receives a real frequency signal and a target frequency signal, and generates a first signal according to the real frequency signal and the target frequency signal. The second signal generating circuit generates a second signal according to the first signal. The PWM circuit generates a PWM signal according to the second signal. The switching circuit is electrically connected with the PWM circuit and outputs a control signal to control the rotary speed of the motor. Hence, the fan rotary speed controlling device boosts the accuracy and the stability of the fan rotary speed.

Abstract: A fan rotary speed controlling device includes a base voltage generating circuit, a first voltage generating circuit, a second voltage generating circuit and a compensation controlling circuit. The base voltage generating circuit receives a pulse width modulation signal and outputs a base voltage signal. The first voltage generating circuit receives the pulse width modulation signal and generates a first voltage signal according to the pulse width modulation signal. The second voltage generating circuit receives a fan rotary speed signal and generates a second voltage signal according to the fan rotary speed signal. The compensation controlling circuit outputs a voltage deviation compensation signal according to the first voltage signal and the second voltage signal. Hence, the fan rotary speed controlling device provides a stable rotary speed.

Abstract: A motor control apparatus and a motor control method determine whether the motor is in a back-pressure area so as to provide different rotation-speed control signals. When the fan is in the low duty cycle, a first circuit loop is switched on, so that the fan has more accurate rotation speed. When the fan is in the high duty cycle, a second circuit loop is switched on, so that the rotation speed of fan does not be limited to a constant rotation-speed as the fan enters the back-pressure area. Thus, the fan has larger airflow quantity and higher airflow pressure.

Abstract: A motor control apparatus and a motor control method determine whether the motor is in a back-pressure area so as to provide different rotation-speed control signals. When the fan is in the low duty cycle, a first circuit loop is switched on, so that the fan has more accurate rotation speed. When the fan is in the high duty cycle, a second circuit loop is switched on, so that the rotation speed of fan does not be limited to a constant rotation-speed as the fan enters the back-pressure area. Thus, the fan has larger airflow quantity and higher airflow pressure.

Abstract: A motor control method and a motor control device are provided. The control method includes the steps of receiving a current feedback signal from a coil switching circuit, while the motor is rotating, for generating a separate signal, and comparing the current feedback signal and the separate signal for generating a motor control signal so as to control the operation of the motor.

Abstract: A motor control apparatus and a motor control method determine whether the motor is in a back-pressure area so as to provide different rotation-speed control signals. When the fan is in the low duty cycle, a first circuit loop is switched on, so that the fan has more accurate rotation speed. When the fan is in the high duty cycle, a second circuit loop is switched on, so that the rotation speed of fan does not be limited to a constant rotation-speed as the fan enters the back-pressure area. Thus, the fan has larger airflow quantity and higher airflow pressure.

Abstract: A motor control apparatus includes a sensing module, a phase modulating module, a duty cycle modulating module and a driving module. The sensing module detects a motor to generate a sensing signal. The phase modulating module receives the sensing signal and generates a phase modulation signal in accordance with the sensing signal. The duty cycle modulating module receives the phase modulation signal and generates a duty cycle modulation signal in accordance with the phase modulation signal. The driving module receives the duty cycle modulation signal and generates a motor control signal for controlling the motor in accordance with the duty cycle modulation signal.

Abstract: A motor control method and a motor control device are provided. The control method includes the steps of receiving a current feedback signal from a coil switching circuit, while the motor is rotating, for generating a separate signal, and comparing the current feedback signal and the separate signal for generating a motor control signal so as to control the operation of the motor.