SWITCHED CAPACITOR FILTER, LOW-PASS FILTER EMPLOYING THE SAME, STANDARD RADIO WAVE RECEPTION CIRCUIT, AND ELECTRONIC APPARATUS WITH RADIO WAVE CORRECTION FUNCTION

摘要

PROBLEM TO BE SOLVED: To provide a switched capacitor filter which reduces influences of parasitic capacitance of the switched capacitor filter and has loss-reduced and gain-improved filter properties, a low-pass filter employing the same, a standard radio wave reception circuit and an electronic apparatus with a radio wave correction function.SOLUTION: A switched capacitor filter 1 comprises a capacitor CL that is a first capacitive element for forming the filter, and an equivalent resistor 2. The equivalent resistor 2 includes: a capacitor CS that is a second capacitive element different from the capacitor CL; first switch elements SW1 and SW2 connected to a terminal of the capacitor CS for charging the capacitor CL and the capacitor CS; and second switch elements SW3 and SW4 of which one terminal is connected to a terminal of the second capacitive element CS, for discharging the second capacitive element CS. A potential at the other terminal of the second switch elements SW3 and SW4 is equal to that of output (out) of the equivalent resistor 2.SELECTED DRAWING: Figure 1