Abstract: A circuit for providing a plurality of output functions at respective outputs by detecting the presence of an unusual voltage applied at its input thereof, comprising input circuit coupled to the input for transferring the input signal to a first output when the input signal is within a predetermined voltage range. A detection circuit coupled to the input for providing a detection signal at an output thereof when the input signal level exceeds a predetermined level in a predetermined sense. A buffer stage coupled between the output of the detection circuit and a second output, responsive to the detection signal, for providing a first binary logic state of the second output.