Analogue fault simulation

Analogue testing often takes a functional approach. However, a number of structural (fault-orientated) approaches are being investigated and have been shown to have advantages such as reliability indication. One of the main problems with a structural approach is the lengthy run times for analogue fault simulation (AFS). The paper describes the use of higher level modelling of analogue functional blocks as part of a multi-level simulation in order to accelerate AFS, and assesses its impact in terms of speedup and accuracy. Software tools which have been developed to give an indication of fault coverage for analogue circuits are also described. The paper concludes that a mixed-mode approach can reduce AFS time for larger circuits without excessive loss of accuracy