US Patent 9275256 Semiconductor integrated circuit

A method of a semiconductor integrated circuit comprising a logic circuit including n storage elements (n is a positive integer) which can each store 1-bit information and an attack detection circuit, the method including detecting, by an error determination circuit, through a logic operation that k-bit or less errors (k is a positive integer) have occurred in n-bit codes stored in the n storage elements, and detecting, by a light irradiation detection circuit which includes light detection elements, that light has been irradiated to (k+1) or more of the n storage elements. It is determined that the logic circuit has been attacked from outside when the error determination circuit detects an error or the light irradiation detection circuit detects light irradiation.