DEMULTIPLEXER AND SURFACE ACOUSTIC WAVE FILTER

摘要

A demultiplexer ensuring sufficient attenuation quantity and bandwidth in the working temperature range. The demultiplexer (1) comprises a first filter (11) having a relatively low pass band and provided with first temperature characteristics improving thin film, and a second filter (12) having a relatively high pass band and provided with second temperature characteristics improving thin film, wherein the thicknesses of the first and second temperature characteristics improving thin films are differentiated such that the frequency temperature coefficient of the first filter becomes larger than that of the second filter.