Diplexer, and high-frequency switch and antenna duplexer using the same

摘要

A diplexer capable of passing signals of a high frequency band without being attenuated over a wide frequency band, and a high-frequency switch using the diplexer are provided. The diplexer includes a low-pass filter (82) having a parallel resonant circuit formed by a first capacitor (C1) and a first inductor (L1) and a serial resonant circuit formed by a second capacitor (C2) and a second inductor (L2). With this structure, two attenuation poles are provided in the low-pass filter (82). Thus, a passband of a high-pass filter (83) can be widened. <IMAGE>