US Patent 10018202 Fan control system

A fan control system includes a control module, a first fan module and a second fan module. The control module provides a first control signal to the first fan module to adjust the rotation state of the first fan module. The first fan module provides a second control signal to the second fan module based on the first control signal to adjust the second fan module. The first fan module includes a first terminal and a second terminal. The second fan module includes a first terminal and a second terminal. The first terminal of the first fan module is electrically connected to the control module to receive the first control signal. The second terminal of the first fan module is electrically connected to the first terminal of the second fan module. The second terminal of the second fan module is electrically connected to a reference voltage.