Abstract: A circuit board adapted to a fan comprises a circuit region and a heat-dissipative film. The circuit region is provided on a first surface of the circuit board and comprises at least one heat-generating component thereon. The heat-dissipative film is coated on an edge portion of the first surface and is in contact with the heat-generating component. A plurality of openings through the heat-dissipative film, a protrusion of the circuit board, a cutout in the protrusion to expose the heat-generating component to airflow, etc., have been disclosed and claimed for enhancing the efficiency in heat dissipation. A heat sink may also be provided on a second surface opposite to the first surface of the circuit board. The heat sink is connected to the heat-dissipative film to help dissipate the heat generated by the operation of the fan.

Abstract: A switch control device receives an input signal and a power signal and includes a control unit and a switch unit. The control unit has a predetermined value and receives the input signal and the power signal. When the input signal is lower than the predetermined value, the control unit outputs a control signal. The switch unit is electrically connected with the control unit, receives the control signal, and stops outputting the power signal according to the control signal.

Abstract: A circuit board adapted to a fan comprises a circuit region and a heat-dissipative film. The circuit region is provided on a first surface of the circuit board and comprises at least one heat-generating component thereon. The heat-dissipative film is coated on an edge portion of the first surface and is in contact with the heat-generating component. A plurality of openings through the heat-dissipative film, a protrusion of the circuit board, a cutout in the protrusion to expose the heat-generating component to airflow, etc., have been disclosed and claimed for enhancing the efficiency in heat dissipation. A heat sink may also be provided on a second surface opposite to the first surface of the circuit board. The heat sink is connected to the heat-dissipative film to help dissipate the heat generated by the operation of the fan.

Abstract: A fan motor speed control circuit and a voltage-regulating module thereof are disclosed. The fan motor speed control circuit includes the voltage-regulating module and a driving module electrically connected to the voltage-regulating module. The driving module includes a pulse signal generating unit, a speed control unit, and a drive unit. The speed control unit compares a high frequency pulse signal generated by the pulse signal generating unit with a variable reference voltage signal output by the voltage-regulating module, and then outputs a control signal to the drive unit to proceed the speed control of the fan motor. In application, the voltage-regulating module and the driving module are electrically connected to a voltage source in parallel.

Abstract: A switch control device receives an input signal and a power signal and includes a control unit and a switch unit. The control unit has a predetermined value and receives the input signal and the power signal. When the input signal is lower than the predetermined value, the control unit outputs a control signal. The switch unit is electrically connected with the control unit, receives the control signal, and stops outputting the power signal according to the control signal.

Abstract: A fan motor speed control circuit and a voltage-regulating module thereof are disclosed. The fan motor speed control circuit includes the voltage-regulating module and a driving module electrically connected to the voltage-regulating module. The driving module includes a pulse signal generating unit, a speed control unit, and a drive unit. The speed control unit compares a high frequency pulse signal generated by the pulse signal generating unit with a variable reference voltage signal output by the voltage-regulating module, and then outputs a control signal to the drive unit to proceed the speed control of the fan motor. In application, the voltage-regulating module and the driving module are electrically connected to a voltage source in parallel.

Abstract: A circuit board adapted to a fan comprises a circuit region and a heat-dissipative film. The circuit region is provided on a first surface of the circuit board and comprises at least one heat-generating component thereon. The heat-dissipative film is coated on an edge portion of the first surface and is in contact with the heat-generating component. A plurality of openings through the heat-dissipative film, a protrusion of the circuit board, a cutout in the protrusion to expose the heat-generating component to airflow, etc., have been disclosed and claimed for enhancing the efficiency in heat dissipation. A heat sink may also be provided on a second surface opposite to the first surface of the circuit board. The heat sink is connected to the heat-dissipative film to help dissipate the heat generated by the operation of the fan.