| 摘要 |
PURPOSE:To make it possible to perfectly and rapidly perform the test of LSI, by independently performing the test LSI while electrically separating LSI and the other circuit on a substrate. CONSTITUTION:When a low level testing machine control signal S is inputted to buffers 2, 5, 6 directly and inputted to buffers 3, 4 through AND circuits 7, 8, the buffers 2-6 are brought to a high impedance state and LSI1 is electrically separated from the other circuit on a substrate. In this state, a signal is applied to each pin of LSI1 to enable the independent testing of LSI1. Because the buffers 2-6 merely function as buffer, any influence is not imparted to the function of the substrate and any problem is not generated. |
