Patent ID: 8285887

Claim:
A link detection system for a network cable, for detecting a connection state of the network cable, comprising: a network state detection unit generating a first signal, configured such that the first signal changes from a first value to a second value when a network cable is linked to a network interface and electrical signals are received from the network cable via the network interface; a LAN controller generating a second signal, configured such that the second signal changes from a first value to a second value when the network cable is unplugged from the network interface; a control unit generating a power switching signal to control an ON and OFF status of a power supply of the LAN controller, the power switching signal being generated according to the first and second signals, configured such that the power supply is switched ON when the first signal changes from the first value to the second value thereof, and the power supply is switched OFF when the second signal changes from the first value to the second value thereof, configured such that the LAN controller is turned OFF when the network cable is unplugged from the network interface, and turned ON when the network cable is both plugged back in and electrical signals are received from the network cable via the network interface, and further configured such that the first signal is generated by the network state detection unit according to a pulse signal also generated by the network state detection unit, the pulse signal having an oscillating value when electrical signals are received from the network cable via the network interface, and a constant value when electrical signals are not received from the network cable via the network interface, the first signal changing from a first value to a second value when the pulse signal changes from a constant value to an oscillating value, wherein the pulse signal is generated both when the network cable is plugged into the network interface and when it is unplugged from the network interface.