| 摘要 |
PURPOSE:To discriminate a trouble of a wiring under test or a trouble of a scan circuit for circuit test if no coincidence is obtained between the outputted value and the expected value and at the same time to specify a trouble area of the scan circuit. CONSTITUTION:A scan circuit for circuit test is contained in a circuit 1 and outputs the value of a prescribed area of a tested circuit 2 to a circuit tester with a read signal received from the circuit tester. In this case, the scan circuits 3 and 4 are provided in two systems independent of each other. A first scan circuit 3 performs the test of the circuit 2 and at the same time inputs the test signals to each point of a second scan circuit 4 to output an answer signal to the circuit tester for execution of the test of the circuit 4. Meanwhile the second scan circuit 4 inputs the test signals to each point of the first circuit 3 and also outputs an answer signal to the circuit tester for execution of the test of the first scan circuit 3. |
