Patent ID: 8000079

Claim:
An electronic device comprising: a control unit generating a control signal according to an external signal; a current limiting circuit receiving the external signal, and drawing an amount of current that does not exceed a current threshold from the external signal; an energy storage component coupled electrically to said current limiting circuit for receiving the current from said current limiting circuit so as to store energy therein; a latching relay coupled electrically to a common node of said current limiting circuit and said energy storage component, said latching relay including a switch, and first and second coils, each of said first and second coils having first and second terminals, a common node of said current limiting circuit and said energy storage component being connected electrically to said first terminals of said first and second coils of said latching relay; a switch circuit coupled electrically to said energy storage component, and controlled by the control signal to selectively enable said energy storage component to discharge the energy stored therein so as to drive said latching relay, said switch circuit being controlled by two of the control signals, said switch circuit including: a first transistor coupled electrically to said second terminal of said first coil of said latching relay, and controlled by a first one of the control signals to selectively enable said energy storage component to discharge the energy stored therein to said first coil of said latching relay for turning off said switch of said latching relay; and a second transistor coupled electrically to said second terminal of said second coil of said latching relay, and controlled by a second one of the control signals to selectively enable said energy storage component to discharge the energy stored therein to said second coil of said latching relay for turning on said switch of said latching relay; a main operating component and a power supplying member connected electrically to said main operating component for driving operation of said main operating component, said switch of said latching relay having a first terminal that is adapted to be connected electrically to an external power source, and a second terminal that is connected electrically to said power supplying member for transmitting power supplied by the external power source to said power supplying member when said switch is turned on, so as to enable said power supplying member to drive operation of said main operating component, said main operating component being a liquid crystal display panel, the external signal including a power signal component and an image signal component, said control unit generating the control signals according to the image signal component, said current limiting circuit drawing the current from the power signal component.