Patent ID: 7492112

Claim:
An apparatus for receiving a voltage signal from a signal source to control a rotating direction of a fan, the apparatus comprising: a power source; a first node being connected to the power source via a first resistor; a second node being connected to the power source via a second resistor; a first trigger comprising an input terminal being connected to the first node and an output terminal; a second trigger comprising an input terminal being connected to the second node and an output terminal; a first transistor being connected between the signal source and the first node for controlling the power from the power source receivable by the first trigger; and a second transistor being connected between the first node and the second node for controlling the power from the power source receivable by the second trigger; an activating module comprising a first input terminal and a second input terminal both of which are connected to the output terminal of the first trigger and the output terminal of the second trigger; a first negation gate being connected between the second input terminal of the activating module and the output terminal of the first trigger; and a second negation gate being connected between the first input terminal of the activating module and the output terminal of the second trigger.