Patent ID: 8310837

Claim:
A circuit module comprising: a first laminated board that has a first insulating layer, a first conductive layer laminated on said first insulating layer, a second insulating layer laminated on said first conductive layer, and a second conductive layer laminated on said second insulating layer; an integrated circuit that is mounted on said first insulating layer and that has a plurality of ground terminals, and performs at least one of modulation and demodulation of a power line communication signal transmitted via a power line that supplies electric power to the circuit module; and a filter that is connected to the power line and mounted on a surface of said circuit module and that outputs a signal which has a continuous frequency range of the power line communication signal, the filter being mounted on a surface different from said first insulating layer; wherein the power line communication signal is filtered by the filter connected to the power line and output on the power line; said first conductive layer is electrically connected to said plurality of ground terminals, by a plurality of vias, and is not electrically connected to the second conductive layer; and the plurality of vias penetrate only the first insulating layer, and do not penetrate the second insulating layer, wherein the power line has a pair of lines.