Patent ID: 7913316

Claim:
A semiconductor integrated circuit including a non-volatile device for storing confidential data, wherein the non-volatile device is configured so that stored data cannot be read out to the outside of the semiconductor integrated circuit, the semiconductor integrated circuit comprises: a redundant data storing section for storing check redundant data obtained by subjecting the confidential data to a predetermined computation; and a test circuit for executing a test on the non-volatile device using the check redundant data stored in the redundant data storing section, the test circuit comprises: a check computation circuit for executing a computation corresponding to the predetermined computation with respect to the confidential data read from the non-volatile device; a comparison circuit for comparing a result of the computation in the check computation circuit with the check redundant data stored in the redundant data storing section; and an encryption circuit for encrypting the confidential data and the check redundant data using a predetermined secret key, and when a mismatch between the computation result and the check redundant data is detected as a result of the comparison in the comparison circuit, a result of the encryption in the encryption circuit is output to the outside of the semiconductor integrated circuit, wherein only when the encryption circuit receives a signal indicating mismatch from the comparison circuit, the encryption circuit outputs an encrypted data corresponding a portion of mismatch between the computation result and the check redundant data.