| 摘要 |
PURPOSE: A band pass filter for a tuner is provided to operate without a discrete device such as an inductor in the tuner and band-pass filter a difference component. CONSTITUTION: The device extracts the difference component in a mixer signal including the difference and sum components between an RF signal having a very high frequency or an ultra high frequency of band and a signal for selecting channels. A low pass filter(60) filters the low pass component of the mixer signal to output the filtered results. A high pass filter(80) filters the high band components of the filtered results responding to the current for bias input from the external to output the filtered results as the difference components. The low pass filter includes the first capacitor connected between the mixer signal and the results filtered from the low pass filter, and a resistor connected between the results filtered from the low pass filter and the reference voltage. |
