FILTER AND MULTIPLEXER

• Main Authors: TASAKA NAOYUKI, AMANO TAKASHI
• Format: Patent
• Language: English; Japanese
• Published: 17.09.2020
• Subjects: BASIC ELECTRONIC CIRCUITRY; ELECTRICITY; IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS

To improve a temperature characteristic.SOLUTION: A filter comprises: an input terminal; an output terminal; a resonance circuit that includes capacitors and an inductor which are connected in parallel between the input terminal and the output terminal; and an acoustic wave resonator, in which one end is connected to the capacitor or one end of the inductor, the other end is grounded, and a resonance frequency is positioned in between a passband and the resonance frequency of the resonance circuit, and that has a temperature coefficient which is a symbol being opposite to a symbol of a temperature coefficient of the resonance frequency of the resonance circuit.SELECTED DRAWING: Figure 1 【課題】温度特性を向上させること。【解決手段】入力端子と、出力端子と、前記入力端子と前記出力端子との間に並列接続されたキャパシタとインダクタとを備える共振回路と、一端が前記キャパシタまたは前記インダクタの一端に接続され、他端が接地され、共振周波数は、通過帯域と前記共振回路の共振周波数との間に位置し、前記共振回路の共振周波数の温度係数の符号と反対の符号の温度係数を有する弾性波共振器と、を備えるフィルタ。【選択図】図１