An airflow detection apparatus configured to detect airflow of a fan
includes a first transistor, an amplifier, an A/D converter, a
microprocessor, an indicating circuit, and a stabilizing circuit
configured for supplying a stable current to the first transistor. The
base and the collector of the first transistor are connected to a power
supply. The emitter of the first transistor is connected to the amplifier
and the stabilizing circuit. The amplifier receives a voltage signal from
between the base and the emitter of the first transistor. The voltage
signal is converted into a digital signal by the A/D converter. The
microprocessor processes the digital signal and output an indicating
signal to the indicating circuit to indicate airflow status of the fan.