公开(公告)号：US07479848B2

公开(公告)日：2009-01-20

申请号：US12055414

申请日：2008-03-26

申请人： Katsuhito Kuroda

发明人： Katsuhito Kuroda

IPC分类号： H03H9/00 ,  H03H9/54 ,  H01L41/08

CPC分类号： H03H9/6433 ,  H03H7/01 ,  H03H7/175

摘要： In an acoustic wave filter device, a first filter circuit portion includes a first inductor provided in a series arm that couples an input terminal and an output terminal is serially connected to a first acoustic wave resonator, and a second filter circuit portion includes a second inductor provided in the series arm and second and third acoustic wave resonators and connected between one end and the other end of the second inductor and a ground potential. When the pass band center frequency is set as a first center frequency and the center frequency of a filter defined by the inductance of the first and second inductors and the capacitance of the first to third acoustic wave resonators is set as a second center frequency f2, f1 is less than f2.

摘要翻译： 在声波滤波器装置中，第一滤波器电路部分包括设置在串联臂中的第一电感器，其耦合输入端子，并且输出端子串联连接到第一声波谐振器，第二滤波器电路部分包括第二电感器 设置在串联臂和第二和第三声波谐振器中并且连接在第二电感器的一端与另一端之间并具有接地电位。 当通带中心频率被设置为第一中心频率，并且由第一和第二电感器的电感定义的滤波器的中心频率和第一至第三声波谐振器的电容被设置为第二中心频率f2时， f1小于f2。