| 摘要 |
PURPOSE: A complex tuner improving a dynamic range of an input signal level is provided to improve the dynamic range of the input signal level by amplifying or reducing an input signal according to the intensity of the input signal through a dynamic range improving circuit. CONSTITUTION: A dynamic range improving circuit(110) reduces a noise of an input high frequency signal. The dynamic range improving circuit reduces the intensity of the input high frequency signal. A high-frequency amplifier(130) amplifies the input high frequency signal. An MOPLL(Mixer Oscillator Phase Locked Loop) IC(Integrated Circuit)(150) feeds back the input high frequency signal to the dynamic range improving circuit and the high-frequency amplifier according to an AGC(Auto Gain Control) signal. The MOPLL IC reconverts the input high frequency signal into an IF(Intermediate Frequency) signal. [Reference numerals] (111) Dual LNA; (113) Damping circuit; (120) Input tuning filter; (130) RF amplifier; (140) Single-tuning filter; (150) MOPLLIC IC; (160) IF amplifier; (170) SAW filter; (180) Demodulation unit; (AA) Inputting a high frequency(RF) signal; (BB) AGC2; (CC) AGC1; (DD) Outputting an audio/video signal |
