Fan delay control circuit

• Main Authors: QIU XUNUN, YUAN GUANG-DONG
• Format: Patent
• Language: English
• Published: 30.07.2013
• Subjects: BLASTING; CONTROL OR REGULATING SYSTEMS IN GENERAL; CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORSOR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER; ELECTRICITY; EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; GENERATION; HEATING; LIGHTING; MECHANICAL ENGINEERING; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS ORELEMENTS; NON-POSITIVE DISPLACEMENT PUMPS; PHYSICS; POSITIVE DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS; REGULATING; WEAPONS

A fan delay control circuit includes a fan connector connected to a fan of an electronic device, a power supplying module connected to the fan connector, and a rotational speed controlling module connected to the power supplying module. The power supplying module is connected to a fan power source and a stand-by power source. The power supplying module may continue to supply power to the fan when the electronic device including the fan is powered off. The rotational speed controlling module includes a square wave generation circuit which generates a square wave signal to control a rotational speed of the fan even when the electronic device is powered off.