Wireless IC device

摘要

A wireless IC device and a component for a wireless IC device having a stable frequency characteristic are provided.
The wireless IC device includes a wireless IC chip (5), a power feeding circuit board (10) having the wireless IC chip (5) mounted thereon and including a power feeding circuit (16), where the power feeding circuit (16) includes a resonance circuit having a predetermined resonance frequency, and a radiating plate (20) bonded to a lower surface of the power feeding circuit board (10).
The resonance circuit is composed of an LC resonance circuit including an inductance element (L) and capacitance elements (C1) and (C2). The power feeding circuit board (10) is a rigid multilayer board or a rigid single-layer board. The power feeding circuit board (10) is connected to the wireless IC chip (5) and the radiating plate (20) via DC connection, magnetic coupling, or capacitive coupling.