| 摘要 |
An object is to provide a semiconductor device which operates stably even when the communication distance between a reader/writer and a non-contact data carrier is largely changed. A protection circuit is provided in the non-contact data carrier, and an operating state and a non-operating state of the protection circuit are switched depending on the communication distance between the reader/writer and the non-contact data carrier. The operating point at which the operating state and the non-operating state of the protection circuit are switched is different between the case where input voltage of the protection circuit is low in an initial state and then gradually raised and the case where input voltage of the protection circuit is high in an initial state and then gradually lowered. |
