Device for controlling rotation rate of the fan and rate-determining method thereof

• Main Authors: Liao, Chin-Chun, Lee, Wen-Huang, Yang, Tzu-Shiou
• Format: Patent
• Language: English
• Published: 18.09.2003

A fan rotation rate control device and the method thereof for controlling the rotation rate of the fan are provided. The fan outputs actual rotation rates and the control device includes a fan, a control unit, a processing unit and a thermal sensing unit. The thermal sensing unit is used to sense the temperature inside the heat generating device or the temperature of the heat source therein and outputs thermal sensing signals accordingly; the processing unit is coupled to the thermal sensing unit and receives the thermal sensing signal on which the determination of the preset rotation rate is based. Of which, the control unit which is coupled to the processing unit and the fan receives the preset and the actual rotation rates, while the control unit outputs modulation signals to the fan according to the difference between the actual and the preset rotation rates to achieve a precise control of the fan.