Wireless IC device

摘要

An electromagnetic coupling module includes a wireless IC chip and a functional substrate. The electromagnetic coupling module is mounted on a radiation plate, preferably using an adhesive, for example. On the upper surface of a base material of the radiation plate, two long radiation electrodes are provided. On the undersurface of the functional substrate, capacitive coupling electrodes that individually face inner ends of the radiation electrodes are provided. A matching circuit arranged to perform the impedance matching between the wireless IC chip and each of the radiation electrodes includes the capacitive coupling electrodes. As a result, it is possible to reduce the size, facilitate the design, and reduce the cost of a wireless IC device.

主权项

1. A wireless integrated circuit (IC) device comprising:
a wireless IC chip including first and second IC terminals; a radiation plate including first and second radiation terminals arranged on a base material, the first radiation terminal being connected to the first IC terminal, and the second radiation terminal being connected to the second IC terminal; and a functional substrate including a matching circuit including first and second inductance elements disposed inside the functional substrate, the wireless IC chip being mounted on the functional substrate so as to define a module, and the module being mounted on the base material so as to connect the wireless IC chip with the radiation plate via the matching circuit; wherein a first end of the first inductance element is connected to one of the first or second IC terminals and a second end of the first inductance element is connected to one of the first or second radiation terminals; a first end of the second inductance element is connected to the first radiation terminal and a second end of the second inductance element is connected to the second radiation terminal; and the matching circuit is configured such that a relationship between a reactance component of an impedance obtained by viewing the wireless IC chip from a connecting portion connecting the wireless IC chip and the functional substrate to each other and a reactance component of an impedance obtained by viewing the radiation plate from the connecting portion connecting the wireless IC chip and the functional substrate to each other is a conjugate relationship.