| 摘要 |
PROBLEM TO BE SOLVED: To provide a digital/analog common tuner with which sufficient attenuation quantity can be obtained in a tuner for receiving digital broadcast waves and analog broadcast waves. SOLUTION: The sufficient attenuation quantity can be obtained since an AGC circuit 22, a buffer amplifier 23 and an AGC (automatic gain control) circuit 25 are connected in this order between an input terminal 21 and a mixing circuit 27. In addition, distortion can be improved since the digital/analog common tuner is constituted so as to attenuate the AGC circuit 22 prior to the AGC circuit 25. Thus, the first AGC circuit is connected the second AGC circuit between the input terminal and the mixing circuit via the buffer amplifier, damping characteristics are set so that the first AGC circuit is greatly attenuated prior to the second AGC circuit and the first and second AGC circuits can be controlled by an AGC signal to be formed based on a signal to be outputted from an analog demodulator to be connected with the first output terminal or a digital demodulator to be connected with a second output terminal. COPYRIGHT: (C)2004,JPO&NCIPI
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