Patent ID: 7583798
Filing Date: 2009-09-01
Classification: H04M

Abstract:
1. An apparatus for protecting a multi-function product from a surge voltage, the multi-function product comprising a network connection unit which receives one of a ring signal, an information signal and transmits the signal via first and second signal lines and an external apparatus connection unit which is connected to an external apparatus, the apparatus comprising: a first surge voltage cut off device having first and second terminals, wherein the first terminal is connected to the first signal line and the second terminal is connected to the second signal line; a second surge voltage cut off device having first and second terminals, wherein the first terminal is connected to the first signal line; a switching unit having a first terminal connected to the second signal line and a second terminal connected to one of a first contact point connected to the external apparatus connection unit and a second contact point connected to the second terminal of the second surge voltage cut off device; and a control unit which senses a signal received from the multi-function product and controls the second terminal of the switching unit to be switched between one of the first contact point and the second contact point.