| 摘要 |
PURPOSE:To make it possible to easily and rapidly trace an obstruction, by comparing output signals of a test integrated circuit and a same kind of a reference integrated circuit. CONSTITUTION:When a reset switch RK is closed, the input terminal I2 of a FF circuit is set to a logical value 1 and the FF circuit is brought to a reset state while output terminals Q1, Q2 are set to logical values 0, 1 and a green light emitting diode L1 emits light and a red light emitting diode L2 emits no light. In this state, a reference integraed circuits ICS is mounted to a socket SCT and the terminal of a test integrated circuit ICX is held by a clip CLP. Further, selection switches among selection switches SK1-SK15 corresponding to the circuits ICS, ICX are closed and ones corresponding to the output terminals are brought to an open state. When a predetermined test signal is inputted to the input terminal of the socket SCT, the circuits ICS, ICX begin to operate simultaneously and the output signals thereof are compared to each other by correspoding exclusive logical sum gates G1-G15 and, when even one of the output signals is different, the green light emittin diode L1 stops light emission and the red light emitting diode L2 emits light. |
