Circuit with switch for discharging capacitive elements connected to a safety-related digital input
AssigneeWAGO Verwaltungsgesellschaft mbH
InventorsKarl Heckemann, Torsten Meyer, Christian Voss
Life of this patent
Estimating the term…
Abstract
A circuit is provided that has a safety-related digital input and an input circuit downstream of the safety-related digital input. The input circuit has a comparator circuit connected to the safety-related digital input and arranged to output a first value when a voltage applied to the comparator circuit is in a first range and to output a second value when the voltage applied to the comparator circuit is in a second range. The input circuit is also arranged to close a switch connected to the safety-related digital input for discharging capacitive elements in preparation for a test and to evaluate the voltage applied to the comparator circuit during the test.
Claims14
A circuit comprising:
- a safety-related digital input;
- an input circuit arranged downstream of the safety-related digital input, the input circuit comprising a comparator circuit that is connected to the safety-related digital input and configured to output a first value if a voltage applied to the comparator circuit is in a first range and to output a second value if the voltage applied to the comparator circuit is in a second range;
- an output;
- and
- an output circuit arranged upstream of the output,
- wherein the input circuit is further configured to close a switch connected to the safety-related digital input to discharge capacitive elements in preparation of a test and to evaluate the voltage applied to the comparator circuit during the test,
- wherein the circuit is configured to output a voltage at the output,
- wherein a voltage applied to the safety-related digital input is controlled by the voltage output at the output, and
- during the test, it is checked whether the voltage applied to the safety-related digital input drops to zero when the output of the voltage at the output is interrupted by the output circuit.
Dependencies are inferred from the claim text.