Contactless communication apparatus

Abstract

A contactless communication apparatus includes a board, a semiconductor component, an antenna pattern, a first ground pattern, a second ground pattern, a first wiring portion, a second wiring portion, a third wiring portion, and a return path. The board includes a first surface and a second surface that is situated opposite to the first surface. The semiconductor component includes an output terminal and a ground terminal, and is provided on the first surface. The antenna pattern includes a start end that is an outer peripheral end, and a termination end that is an inner peripheral end. The antenna pattern is a coil-shaped pattern that is formed on the second surface. The first ground pattern is formed along a peripheral edge portion of the first surface. The second ground pattern is formed in an air-core portion of the antenna pattern formed on the second surface, and is connected to the first ground pattern. The first wiring portion connects the output terminal and the start end. The second wiring portion includes a capacitor and connects the first wiring portion and the first or second ground pattern. The third wiring portion connects the first or second ground pattern and the ground terminal. The return path passes through the first wiring portion, the second wiring portion, the first or second ground pattern, and the third wiring portion. The area of a portion surrounded by the path accounts for 25% or less of the area of the first surface.

Dependencies are inferred from the claim text.