| 摘要 |
PURPOSE:To easily investigate the cause of a fault when generating line disconnection by recognizing it according to the output of a disconnection detecting circuit just before delay and the output of the disconnection detecting circuit just after switching whether the position of the line disconnection is before or behind a delay circuit. CONSTITUTION:When an out-of-phase state is generated at the clock and data of inputs, a switching system circuit 2 applies prescribed delay, which is successively enlarged, to an input clock CK0 of a delay circuit 1 and selects one of plural output lines for outputting the inputs according to a switching signal from the outside. Then, the phase of the output clock is made coincident with the phase of the data and outputted. When line disconnection is generated, a disconnection detecting circuit 3-1 just before delay detects the interruption of the input data just before the circuit 1, and a disconnection detecting circuit 3-2 just after switching detects the interruption of the data just after the switching system circuit 2. Thus, according to the output of the circuit 3-1 just before delay and the output of the circuit 3-2 just after switching, it can be recognized whether the position of the line disconnection is before or behind the circuit 1. |
