Patent ID: 7349034

Claim:
A television tuner comprising: an integrated circuit having a high-frequency circuit and an interface to which plural types of data including channel selection data are input therein; and an external circuit provided at an outside of the integrated circuit and AC coupled to the high-frequency circuit, wherein address data for specifying the integrated circuit overlaps the channel selection data, wherein the integrated circuit is provided with a power supply terminal to which a power supply voltage is applied and an external circuit connecting terminal DC insulated from the high-frequency circuit and connected to the external circuit, wherein the interface is provided with an address identifying circuit having applied with an address identifying voltage corresponding to the address data and for setting the interface to receive only the channel selection data by the address identifying voltage, wherein the address identifying circuit is connected to the external circuit connecting terminal, and a first resistor is connected between the power supply terminal and the external circuit connecting terminal, and wherein the external circuit connecting terminal is DC shorted to the ground, a second resistor is connected between the external circuit connecting terminal and the ground, or the external circuit connecting terminal is DC insulated from the ground.