MULTILAYER SUBSTRATE MODULE AND PORTABLE WIRELESS TERMINAL

摘要

In a multi-layer substrate module receiving from an external earth node (20) supply of a reference potential (Vss) for grounding, a plurality of ground lines (170-1, 170-2, 170-3) are provided respectively corresponding to a plurality of internal circuits (210, 220, 230). Moreover, a common node (Ncmn) for coupling the ground lines (170-1, 170-2, 170-3) is provided in an insulating layer (105C) of the multi-layer substrate module. The common node (Ncmn) is electrically coupled to the earth node 20 through a ground pin terminal 204 shared by the plurality of internal circuits (210, 220, 230). Preferably, the common node (Ncmn) is provided in the lowest insulating layer of the multi-layer substrate module. Thus, parasitic inductance of the portion through which an earth current flows, that is, the portion common to the plurality of internal circuits (210, 220, 230), can be suppressed with a small number of ground pin terminals. Accordingly, the inflow phenomenon of the earth current between the plurality of internal circuits (210, 220, 230) is prevented, enabling stable operation.