System and method for fail-safe provision of an analog output value

A system for fail-safe provision of an analog output value for a control process to provide functional safety, the system comprising:

• a control unit which specifies a digital output value;
• a converter which converts the digital output value into the analog output value;
• a read-back device which converts the analog output value into a fail-safe digital output value utilizing fail-safe criteria;
• a release device which is configured to output the analog output value to the control process if an originally provided digital output value conforms to the converted fail-safe digital output value;
• wherein in an event of one of (i) non-conformity and or of a plausibility criterion being infringed, a safety action is performed by the control unit, otherwise, the analog output value is output to the control process aided by the release device;
• and
• wherein the converter comprises an analog output assembly, the read-back device comprises an analog input assembly which provides functional safety and the release device comprises a digital output assembly which provides functional safety.

A method for fail-safe provision of an analog output value for a control process which provides functional safety, wherein the output value is specified by a control unit as a digital output value, the method comprising:

• converting the digital output value into the analog output value via a converter;
• converting the analog output value into a fail-safe digital output value utilizing fail-safe criteria via a read-back device;
• comparing an originally provided digital output value with the converted fail-safe digital output value, in an event of the comparison revealing one of (i) a deviation and (ii) a plausibility criterion being infringed, a safety action being performed, otherwise, the analog output value being output to the control process aided by a release device;
• wherein the fail-safe digital output value is generated by the read-back device via two channels and the fail-safe digital output value generated via a first channel is compared with the originally provided digital output value, and the fail-safe digital output value generated via a second channel is additionally compared with the fail-safe digital output value of the first channel.

A system for fail-safe provision of an analog output value for a control process designed for functional safety, the system comprising:

• a control unit which specifies a digital output value;
• a converter which converts the digital output value into the analog output value;
• a read-back device which converts the analog output value into a fail-safe digital output value utilizing fail-safe criteria;
• a release device which is configured to output the analog output value to the control process if an originally provided digital output value conforms to the converted fail-safe digital output value;
• wherein in an event of one of (i) non-conformity and or of a plausibility criterion being infringed, a safety action is performed by the control unit, otherwise, the analog output value is output to the control process aided by the release device;
• and
• wherein the fail-safe digital output value is generated by the read-back device via two channels and the fail-safe digital output value generated via a first channel is compared with the originally provided digital output value, and the fail-safe digital output value generated via a second channel is additionally compared with the fail-safe digital output value of the first channel.