| 摘要 |
PURPOSE:To curtail the area of a test circuit and the number of terminals of test signals by a method wherein a test code train is prepared according to a test signal from outside and rearranged to a serial train to be applied to other integrated circuit areas so that the train is rearranged selectively to a parallel train according to a specified control signal. CONSTITUTION:When a test signal TiN is applied, a test code train TOTp corresponding to a part for TOT of the signal TiN is pick up from a code train generation circuit 30a to be converted to a serial signal TOTs with a parallel/serial conversion circuit 30b. At the same time, a part for CRT of a signal TIN is decoded with a decoder to make one of control signals CTR 1-CTR3 active. When the signal CRT1 is active, the operation of a test circuit in an area 50 is allowed and hence the signal TOTs, is taken into the circuit to be converted into a signal TOTp, which is supplied into the area 50. In this case, a test facilitating structure of a scan type is realized inside the area 50 corresponding to the TOT part of the signal TiN. |
