Patent ID: 7750495

Claim:
A power line adapter, comprising: a power plug, which can be plugged in a power socket, for receiving an AC voltage; a power-transmitting module, connected to the power plug, for converting the AC voltage to a DC supply voltage; a data-transmitting module, connected to the power plug, for transmitting data to the power plug or receiving data from the power plug, wherein the data-transmitting module at least comprises a power line communication circuit and an Ethernet physical layer transceiver; a micro controller, connected to the Ethernet physical layer transceiver, for receiving a link signal and a package signal derived from the Ethernet physical layer transceiver, and generating a control signal in response to the link signal or the package signal; and a switch circuit for receiving the control signal and the DC supply voltage; wherein the switch circuit connects the DC supply voltage to the power line communication circuit if the control signal makes the switch circuit in a close position, and the switch circuit does not connects the DC supply voltage to the power line communication circuit if the control signal makes the switch circuit in an open position.