RESONANCE CIRCUIT AND OSCILLATION CIRCUIT

摘要

PROBLEM TO BE SOLVED: To reduce resonance frequency variation as against board condition variation by connecting the other end of a strip line resonance equipment, the other end of a strip line and the other end of a capacitance element. SOLUTION: The strip line 4 where a tip is opened and which is formed on the same board as that of the strip line resonator 3 and a capacitor 13 are connected to the strip line resonator 3 where the tip is short-circuited. When the thickness of a dielectric board increases here, the characteristic impedance Zoa of the strip line resonator 3 increases. But the characteristic impedance Zob of the strip line 4 is also increased in accordance with the increase of the thickness of the dielectric board so that the change of Zoa is cancelled by the change of Zob. Therefore, the pattern width and length of the strip line resonator 3, the pattern width and length of the strip line 4 and the capacitance value of the capacitor 13 are optimally selected so that the change of the desired resonance frequency is reduced as against the variation of the thickness of the dielectric board.