Safe threshold-detection device for a railway system

摘要

A device for the safe threshold-detection of state information from an analog signal including a decision component and at least two acquisition diversity channels including in series a safe adaptation circuit, an electronic analog-to-digital conversion circuit, and a unit for comparing the digital output signal of the analog-to-digital conversion circuit with a reference signal is provided. The device comprises a fault detection circuit for the mutual comparison of digital output signals from the conversion circuits and supplies a consistency result. The output of the decision component is a function of the consistency result supplied by the fault detection unit and of the comparison results from the comparison units associated with the respective acquisition channels.