本设计为一种温控风扇系统，具有灵敏的温度感测和显示功能，系统AT89C5 单片机作为控制平台对风扇转速进行控制。可由用户设置高、低温度值，测得温度值在高低温度之间时打开风扇弱风档，当温度升高超过所设定的温度时自动切换到大风档，当温度小于所设定的温度时自动关闭风扇，控制状态随外界温度而定。所设高低温值保存在温度传感器DS18B20内部E2ROM中，掉电后仍然能保存上次设定值，性能稳定,控制准确。-The design as a temperature-controlled fan system, with sensitive temperature sensing and display capabilities, the system microcontroller as the control platform AT89C5 fan speed control. User-configurable high and low temperature, the measured temperature value is between the high and low temperature, when the weak windshield opens the fan, when the temperature exceeds the set temperature automatically switch to wind file, when the temperature is less than the set temperature, fan shut down automatically, control the state with the outside temperature dependent. Established by the high and low temperature value is stored in temperature sensor DS18B20 internal E2ROM, the power-down can still be saved after the last set value, performance, stability, control and accurate.