Concurrent detection of erroneous responses in linear analog circuits

This paper presents a novel methodology for concurrent error detection in linear analog circuits. The error-detection circuit monitors the input and some observable internal nodes of the examined circuit and generates an estimate of its output. The estimate coincides with the output in error-free operation, while in the presence of errors, it diverges. Thus, concurrent error detection is performed by comparing the two signals through an analog comparator. In essence, the error-detection circuit operates as a duplicate of the examined circuit, yet it is smaller, in general, and never exceeds the size of an actual duplicate. The proposed methodology is demonstrated on three analog filters.