Provided is a portable information device having an RFID, the device being
a device in which no effect is produced on original communication of the
portable information device for which an EMC measure is taken, the device
having good productivity, and the device keeping communication distance
without damaging portability. A place where an antenna is set is located
on the side of a battery cover of a battery receiving section to make the
communication distance of an incorporated RFID long. A circuit
configuration wherein a condenser for resonance is connected to both ends
of the antenna coil and an IC is connected to an intermediate tap of the
antenna coil is made so as to make it unnecessary that the resonance
frequency of the RFID is individually adjusted and make the production of
the RFID easy. A magnetic material sheet is arranged between the antenna
coil and a battery to ensure a magnetic circuit for causing a magnetic
flux from an external apparatus to pass through the antenna coil of the
RFID and make the Q of the resonance circuit high.