New statistical algorithm for fault location in toleranced analogue circuits

If an electronic circuit fails during field use it is desirable, with a limited number of diagnostic measurements and computation, to locate the faulty component causing circuit failure. In the paper, a simple statistically based algorithm is presented for the location of a single soft fault in toleranced analogue circuits. At the design stage, component faults are statistically characterised on the basis of simulated faults. By reference to this characterisation, diagnostic responses are selected which, when measured in the field and compared with a data-base of simulated faults, will allow the fault `nearest¿ to the measurement to be determined with adequate discrimination. The method is illustrated by application to a 7-component filter.