| 摘要 |
PURPOSE:To always extract a correct detection signal by allowing a pass center frequency of a band pass filter to automatically trace a frequency of a reception signal even when the frequency of the reception signal is fluctuated. CONSTITUTION:The reception circuit is provided with a switched capacitor filter 23 in which a pass center frequency is subject to variable control in response to the frequency of a clock signal fed to a clock terminal and a PLL circuit 26 changing the frequency of the clock signal to the switched capacitor filter 23 corresponding to the frequency of the reception signal, and the output signal of the switched capacitor filter 23 is detected by a detection circuit. |
