To solve problems that the output of a reader-writer received by a non-contact information medium is increased if the communication distance is smaller than a predetermined value, excessive current over the rated value of an IC can occur in an IC module, the IC module is heated to heat and deform a housing appliance.

The current flowing in an antenna coil 102 of the non-contact information medium can be controlled by providing a tuning capacitor 103 capable of varying the capacity on an IC module and a non-contact information medium with the IC module built therein. Therefore, the excessive current exceeding the rated value of IC can be suppressed. Heat generation in the IC module 101 can be prevented, and heat generation and deformation of the housing appliance can also be prevented.