| 摘要 |
PURPOSE: A method for designing stack chip band filter using tapping is provided to facilitate a fabrication and to simplify a structure by designing a band pass filter using a tapping. CONSTITUTION: A filter is consist of four conductor electrodes, of which two are top and bottom shield layers(30) located on opposite end sides, the other two is a coupling capacitor layer(20), and a resonator layer(10) located at a central of the filter and directly tapped to an input and output terminal. An equivalent circuit of the resonator is represented as follows: wherein, in the resonator, Ya is an admittance from a tapping point to a left ground point, Yb is an admittance from a tapping point to a right ground point, d is a distance from short circuit face to a tapping point, L is an actual length, Z sub. o is an impedance. v sub. g is a propagating velocity of a wave in the filter. The length of the resonator is generally a half of pie. Therefore, the greater the capacitance becomes, the shorter than a half of pie becomes the length of the resonator.
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