| 摘要 |
PURPOSE:To increase the detection ratio of a defective integrated circuit, and to reduce a test pattern by providing input terminals for control signals for detecting malfunction, and an exclusive OR operation part for said control signals. CONSTITUTION:Various control signal input terminals A, B, C-Z of an integrated circuit show control signals themselves at the same time. When the control signal A is ''1'' and other control signals B-Z are ''0'' in normal operation, outputs of exclusive OR circuits (EOR) 1, 13, 19, and 22 are ''1'', and outputs of EORs 2-12, 14-18, 20, 21, and 23 are ''0'', so the test signal of an EOR24 is ''1'', judging that various control signals are in normal operation. If even one of the control signals B-Z goes up to ''1'', the test signal of the EOR24 goes down to ''0'', judging that the control signal is in erroneous operation. |
