Patent ID: 8312505

Claim:
A level-shifting device adapted to electrically interconnect a tuner unit and a decoding unit of a digital television receiver, said level-shifting device comprising: an electronic card connector adapted to be electrically connected to a first power source and a second power source, adapted for insertion of an electronic card, and operable to provide a power signal of one of the first and second power sources to the electronic card according to a requirement of the electronic card; a first level-shifting unit adapted to be electrically connected between the tuner unit and said electronic card connector, adapted to receive a predetermined power signal, and operable for shifting a signal level of a digital television output signal of the tuner unit and for providing a level-shifted output to the electronic card via said electronic card connector when the power signal provided by said electronic card connector to the electronic card inserted therein does not match the predetermined power signal; a second level-shifting unit adapted to be electrically connected between the decoding unit and said electronic card connector, adapted to receive the predetermined power signal, and operable for shifting a signal level of a digital television output signal of the electronic card from said electronic card connector and for providing a level-shifted output to the decoding unit when the power signal provided by said electronic card connector to the electronic card inserted therein does not match the predetermined power signal; and a third level-shifting unit adapted to be electrically connected between the decoding unit and said electronic card connector, adapted to receive the predetermined power signal, and operable for shifting a signal level of a control command exchanged between the electronic card and the decoding unit via said electronic card connector and said third level-shifting unit and for providing a level-shifted output to a destined one of the electronic card and the decoding unit via said electronic card connector when the power signal provided by said electronic card connector to the electronic card inserted therein does not match the predetermined power signal.