Abstract: A PWM buffer circuit includes a duty cycle converting circuit and a frequency-fixed PWM signal generating circuit. The duty cycle converting circuit is used for receiving a first PWM signal and then generating a duty cycle reference voltage on the basis of the first PWM signal. The duty cycle reference voltage is a one-to-one mapping function of the first duty cycle. The frequency-fixed PWM signal generating circuit is used for receiving the duty cycle reference voltage and then outputting a second PWM signal with a fixed frequency. The second PWM signal has a second duty cycle, which is determined in accordance with the duty cycle reference voltage. In addition, the second duty cycle is a one-to-one mapping function of the duty cycle reference voltage.

Abstract: A fan system includes a stator magnetic pole, a driving unit and a real-time stopping unit. The driving unit is coupled with the stator magnetic pole and controls a polarity change of the stator magnetic pole in accordance with a driving signal. The real-time stopping unit is electrically connected with the driving unit. When the fan system is powered off, the driving unit enables two ends of the stator magnetic pole to have the same voltage level in accordance with a control signal generated by the real-time stopping unit so that the fan system stops operating immediately.

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: The invention provides a motor driving device including a converter receiving and converting a non-electrical power source, such as light, heat, mechanical or chemical energy, to a first electrical power, and a selector electrically connected between the converter and a motor, for receiving the first electrical power and a second electrical power from a power source, such as an electrical power generator, and outputting the first or second electrical power according to a rotation speed of the motor.

Abstract: A control device for controlling a motor includes a sensing module, a modifying module and a driving module. The sensing module senses the motor to generate a sensing signal. The modifying module receives the sensing signal and generates a phase modifying signal according to the sensing signal. The driving module receives the phase modifying signal and generates a driving current to drive the motor according to the phase modifying signal.

Abstract: A control system for a motor. The control system and the motor receive an external power. The control system comprises a driver and a switch device. The driver is electrically connected to the motor. The switch device is electrically connected between the external power and the driver and turned on or off according to a control signal. The driver drives the motor according to the external power when the switch device is turned on.

Abstract: A motor control device includes a sensing circuit, a phase-shifting circuit, a comparing circuit and a control circuit. The sensing circuit senses the motor to generate a sensing signal. The phase-shifting circuit is electrically connected to the sensing circuit and receives the sensing signal to generate a phase-shifting signal. The comparing circuit is electrically connected to the phase-shifting circuit and receives the phase-shifting signal to generate a comparing signal. The control circuit is electrically connected with the comparing circuit and the motor, and receives the comparing signal to generate a control signal so as to control the rotation speed of the motor.

Abstract: A motor controlling method and apparatus thereof are provided. The control method includes the steps of receiving a switching phase signal of coil while the motor is rotating, for generating a separate signal, comparing the phase signal and the separate signal to generate a first control signal, generating a current feedback signal equivalent to the first control signal, and comparing the current feedback signal and the separate signal for generating a second control signal so as to control the operation of the motor.

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 control circuit of a sensorless motor includes a first coil, a second coil, a first switch circuit, a second switch circuit and an auxiliary switch circuit. The first switch circuit is electrically connected to the first coil and controls a direction of a current flowing through the first coil. The second switch circuit is electrically connected to the second coil and controls a direction of a current flowing through the second coil. The auxiliary switch circuit is electrically connected to and between the first coil and the second coil and controls the directions of the currents flowing through the first coil and the second coil by cooperating with the first switch circuit and the second switch circuit. A control method of a sensorless motor is also disclosed.

Abstract: A motor control circuit and method thereof serving a coil for controlling the motor. The motor control circuit comprises a separated signal generating circuit generating a separated signal and a comparator comparing a first phase signal from a Hall element or a second phase signal from a phase signal generating circuit with the separated signal. Thus, a motor speed control signal is generated to control the motor. The noise is reduced during controlling the motor.

Abstract: A fan speed control device includes a controller, a switch and a voltage regulator. The controller detects a rotation speed signal of the fan to generate a first driving signal when the rotation speed signal is relatively higher than a predetermined rotation speed signal and generates the first driving signal and a second driving signal when the rotation speed signal is relatively lower than the predetermined rotation speed signal. The switch is electrically connected with the controller and receives the first driving signal. The voltage regulator, which is electrically connected with the controller, the switch and the fan, receives the second driving signal, and controls the rotation speed of the fan in accordance with the first driving signal and the second driving signal.

Abstract: A motor control device is used to control a motor to rotate. The motor control device includes a phase-wave signal sampling module, a first waveform modulating module, a second waveform modulating module and a control signal integrating module. The phase-wave signal sampling module outputs a first phase-wave signal and a second phase-wave signal in accordance with the rotation of the motor. The first waveform modulating module generates a first control signal in accordance with the first phase-wave signal. The second waveform modulating module generates a second control signal in accordance with the second phase-wave signal. The control signal integrating module generates a rotation rate control signal in accordance with the first control signal and the second control signal, and inputs the rotation rate control signal to a drive module to control a rotation rate of the motor.

Abstract: A method of adjusting sensitivity of signal interpretation includes the steps of: continuously receiving an input signal; setting a sampling parameter; sampling the input signal according to the sampling parameter to obtain a plurality of sampling signals; judging whether the sampling signals are the same or not; generating a first control signal according to the sampling signals if the sampling signals are the same; and generating a second control signal according to the input signal if the sampling signals are not the same. A device of adjusting the sensitivity of signal interpretation is also disclosed.

Abstract: A protecting device of a fan system includes at least one first switch element and at least one control unit. The first switch element receives a first input signal. The control unit is electrically connected with the first switch element, receives the first input signal, and controls the first switch element to turn on or turn off according to the first input signal. The control unit stops outputting the first input signal when the first switch element turns on. The control unit outputs the first input signal when the first switch element turns off, so that a fan of the fan system can be driven by the first input signal.

Abstract: A full-bridge circuit for a heat dissipation system. The heat dissipation system further includes a fan and a control circuit. The control circuit outputs a first control signal and a second control signal. The full-bridge circuit includes a first control line having a first switch and a third switch serially coupled, a second control line includes a second switch and a fourth switch serially coupled, and a induction coil having one terminal coupled between the first and third switches and the other terminal coupled between the second and fourth switches. The ON/OFF states of the first and second switches are controlled by the first and second control signals respectively. The ON/OFF states of the third and fourth switches are controlled by two driving voltage sources respectively.

Abstract: A hot-swap circuit system for fan tray module includes a soft-start circuit module in charge of the power start of the fan tray module hot-plugged into an application system. The soft-start circuit module includes a capacitor and a field effect transistor. The capacitor discharges and the field effect transistor turns off when an input voltage is changed from a certain value to zero.

Abstract: A motor control method and device. The motor control device includes a programmable integrated circuit (IC) receiving a phase signal, the phase of which is consistent with the rotation phase of a coil of the motor. The programmable IC generates a duty-cycle signal in accordance with the period of the phase signal. The duty-cycle signal comprises a rising segment and a falling segment and when the phase signal changes phase, the duty cycle represented by the duty-cycle signal is a first duty cycle, allowing the input power of the motor remain at a minimum. The duty-cycle signal is input to the coil, controlling the coil on and off and, thereby rotating the motor.

Abstract: The present invention discloses a fan protection apparatus and related method thereof. The fan protection apparatus has a control circuit and a counter. According to the fan protection method, the user can set the acceptable restart number and the special time for auto restart. The fan protection apparatus and method can force to stop the fan when the fan encounters an abnormal situation. When the stop time has passed, the fan is automatically restarted. The present invention counts the number of restarts.