Integrated circuit security system for smart card, has protection circuit with variable capacitor which supplies power supply line with displacement current when integrated circuit device is in active state

摘要

A smart card chip (12) has integrated circuit device (14) with security information, and protection circuit (16). A power supply line (28) is electrically coupled to power supply terminal (Vs) of integrated circuit device, and input of protection circuit. A variable capacitor (14) in protection circuit, supplies power supply line with displacement current (Id) when integrated circuit device is in active state. Independent claims are also included for the following: (1) smart card; and (2) smart card operating method.