Information processing equipment

The present invention relates to an information processing equipment, and more particularly to an information processing apparatus suitable for a tamper resistance device such as an IC card providing high security. A relation between the data process contents in an IC card chip and the consumption current of the IC card chip is reduced. Prior to executing an input data process of the IC card chip, the input data is transformed to thereby reduce the relation between the process data and the consumption current of the IC card chip. After the transforming process, the transformed data is untransformed to obtain a correct process result.