| 摘要 |
PURPOSE:To improve the ability to recover a circuit to be switched and a switch circuit itself from a fault by providing plural switch circuits. CONSTITUTION:For example, circuit units C0, C1, and C2 among units C0-C3 and switch circuit units S0, S1, and S2 among S0-S4 are used to perform normal processing. Further, the output of the C0 is connected to the S0, the C1 is connected to the S1, and the C2 is connected to the S2 logically; and the C3, and S3 and S4 are in stand-by states and have a physical connection relation, but has no logical connection relation. In this case, if the C0, and S1 and S2 become abnormal, the C0, C1, and C2 are switched to, for example, the C1, C2, and C3 respectively to connect the C1 to the S3, the C2 to the S4, and the C3 to the S0, performing normal processing. This results from that a new connection relation is generated even in case of a defect because at least the switch circuit units S0-S4 and circuit units C0-C3 to be switched have a mutual physical connection relation more than the permissible number of defect units (m-k and n-k) originally. |
