| 摘要 |
PURPOSE:To constitute a system switching system with one monitoring circuit without needing a complicated deciding means or control procedure by executing the abnormality detection of a received signal by monitoring a signal after a system is switched and switching the signals of a main system and auxiliary system when abnormality is detected. CONSTITUTION:A switching circuit 1 inputs a main system input signal 1a and auxiliary system input signal 1b respectively to a gate circuit. Then, the signal is selected by a control signal 2a, which is connected directly to one gate circuit and connected through an inverter circuit to the other gate circuit, and a received output signal 1c is outputted. The received output signal 1c from the switching circuit 1 is monitored by a monitoring circuit 2 by using an abnormality detection circuit 3. In the case of the abnormality, the signal 3a is outputted to a flip-flop(FF) circuit 4 and the control signal 2a, whose logical level is inverted, is outputted from the FF circuit 4. After that, the switching circuit 1 switches the input signals of the main system and auxiliary system. Thus, the constitution can be made simple. |
