PURPOSE: To miniaturize the entire filter without deteriorating its branching characteristic by coating conductive films so as to make a part of the 3rd conductive film of the 1st filter adjacent to a part of the 4th conductive film of the 2nd filter and arranging the 3rd conductive film so as to surround other elements of the 1st filter.
CONSTITUTION: An inductor L1 is constituted as a loop of thin films 16, 18. A part of the thin film 16 is adjacent to the thin film 9 of a UHF circuit part, and a stray capacitance caused between the both is connected equivalently to a capacitor C3 in parallel to compensate the capacitance of the capacitor C3. The thin film 9 constituting an inductor L6 is arranged so that a part is made adjacent to a VHF circuit and the other is formed along the ridge of the board 1 and the thin films 14, 15 constituting an inductor L7 are arranged to a part surrounded by the thin film 9. Thus, the region providing the thin film 14 is made broad, the stray capacitance between the thin films 4 (e.g., thin films 9 and 12) constituting the inductors L6, L8 and 14 is reduced and the distributed capacitance produced in the thin film 14 itself is decreased.
KIYOSUE KUNIAKI
TOKUNAGA HIROMI
TAGI HIROMITSU
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