Semiconductor Integrated Circuit

A method of 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 attack detection circuit comprising an error determination circuit and a light irradiation detection circuit having light detection elements, the method comprising:

• detecting, by the 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,
• wherein a plurality of areas surrounding arbitrary (k+1) storage elements of the n storage elements, with a minimum closed curve having no inward convex circumference, each contain at least one light detection element, and the light irradiation detection circuit detects light irradiation to (k+1) or more of the n storage elements at the time of detecting that light has been irradiated to at least one of the light detection elements;
• and
• determining 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.

A method of an attack detection circuit, the method comprising:

• detecting through a logic operation that k-bit or less errors (k is a positive integer) have occurred in n-bit codes stored in n storage elements (where n is a positive integer) which can each store 1-bit information;
• detecting that light has been irradiated to (k+1) or more of the n storage elements;
• and
• determining that a logic circuit including the n storage elements has been attacked from outside when detecting an error or detecting light irradiation.