FILTER, BRANCHING FILTER, COMMUNICATION MODULE, AND COMMUNICATION EQUIPMENT

摘要

A filter of the invention is a filter including a substrate and a filter element mounted on the substrate, wherein the substrate is provided with a plurality of connecting line layers including a connecting line layer for filter which is formed with transmission lines and connected with the filter element, an insulating layer formed at a position interposed between the plural connecting line layers and a ground pattern formed in at least a part of the lower connecting line layer of the connecting line layers for filter; and a thickness dimension of the insulating layer formed at a position interposed between the connecting line layer for filter and the other connecting line layer is smaller than a width dimension of the transmission line formed in the connecting line layer for filter and is larger than a thickness dimension of the other connecting line layer. By taking such a configuration, a thin, high-suppression and high-isolation filter can be realized.