Semiconductor integrated circuit having diagnosis function

摘要

A semiconductor integrated circuit having a diagnosis function includes a scan chain arrangement block 2 in which a plurality of flip-flops are connected so that they can be shift-registered, and designed in a scan-path manner; a shift register 3 for storing required bits of a first random number pattern shifted by the block 2; another shift register 4 for storing required bits of a second random number pattern supplied to the block 2; and a comparator for comparing corresponding bits of the random number patterns stored in the shift registers 3 and 4 to detect whether all the bits of the random number patterns agree or disagree with each other, thereby verifying a normal operation of the block 2. In this configuration, the operating state of the semiconductor integrated circuit can be diagnosed with the number of connecting wires connected to it being minimized.