| 摘要 |
PURPOSE: To output a signal without delaying it by checking an abnormal input signal by an INHIBIT element and outputting a normal input signal almost without delaying it because the inhibiting state of the INHIBIT element is held only for an extremely short period by the sharp rise of the signal. CONSTITUTION: A charging current drives a photocoupler PC2 in a circuit 1 and turns its output D2 to a high level. The output D2 is inputted to the inhibition gate b of the INHIBIT element 7 to turn an abnormal signal to an output inhibiting state during the input of the abnormal signal. Thereby no signal is outputted from an output terminal 4 during the continued period of the abnormal signal regardless of the state of an output D1 from a photocoupler PC1. On the other hand, the rise of a waveform of a normal input signal inputted by the operation of an external contact 2 is sharp, so that a charging current to a capacitor C in the circuit 1 is quickly reduced, the output inhibiting state of the element 7 is quickly released and the output D1 of the photocoupler PC1 is outputted to the output terminal 4 through the input gate a of the element 7. |
