To reliably suppress a change in frequency characteristic caused by a parasitic capacitance.
A filter circuit includes: a voltage/current converter 106 converting a voltage signal input to an input end into a current signal; a first capacitor unit 102 that is formed of a plurality of capacitors, sequentially receives the current signal output from the voltage/current converter 106 per cycle, and adds electric charge of the capacitor of 1 group to which the current signal is input to be output, a second capacitor unit 104 composed of a plurality of capacitors, to which the current signal output from the first capacitor unit 102 is sequentially input per cycle, and adding and outputting the electric charge of a group of the capacitors to which the current signal is input; and a plurality of connection nodes 110, 112, 114, and 116 connecting any capacitor outputting the electric charge in the first capacitor unit 102 to the capacitor of the second capacitor unit 104 individually to which the current signal by the output of the electric charge is input.
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YOSHIZAWA ATSUSHI
Tetsuo Kanamoto
Koji Hagiwara
Kazuki Matsumoto