| 摘要 |
PROBLEM TO BE SOLVED: To solve the problem wherein PLL can erroneously and easily synchronize with noise, or the like of a near frequency of a pilot signal since a capture range is set to be large corresponding to variation in an oscillation frequency according to temperature when composing a VCO for composing the PLL capturing the pilot signal in the stereo demodulation section of an FM tuner using a CR oscillation circuit. SOLUTION: A temperature sensor circuit 94 is provided in a tuner semiconductor chip including the stereo demodulation section 76 to detect temperature of a VCO part. Based on an output signal S<SB>TP</SB>of the temperature sensor circuit 94, an oscillation frequency f<SB>VCO</SB>of the VCO is adjusted to compensate variation in f<SB>VCO</SB>due to temperature, thus setting width of the capture range to be narrow as in the case when a ceramic resonator, or the like is used. COPYRIGHT: (C)2009,JPO&INPIT
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