Catastrophic Fault Diagnosis of a Certain Class of Nonlinear Analog Circuits

Michał Tadeusiewicz,Stanisław Hałgas,Andrzej Kuczyński

doi:10.1007/s00034-014-9857-7

Michał Tadeusiewicz, Stanisław Hałgas + Show 1 more

Open Access

https://doi.org/10.1007/s00034-014-9857-7

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Abstract

This paper deals, for the first time, with catastrophic fault diagnosis of nonlinear analog circuits containing bipolar and MOS transistors having multiple operating points (DC solutions). The faults are cuts of some connecting paths and short-circuits of some pairs of points. Simulation-before-test approach is applied for detection and identification of a single catastrophic fault. To build a fault dictionary, a diagnostic test is arranged based on DC analysis. In the discussed circuits having multiple DC solutions, the tested output voltage may assume different values for fixed value of the input voltage. This fact considerably complicates the fault diagnosis. The crucial point of the proposed approach is tracing large number of nonlinear multivalued input---output characteristics at different values of circuit parameters within their tolerance ranges. For this purpose an efficient and fast algorithm is developed, based on the theory known under the name a linear complementarity problem. To illustrate the proposed approach and show its efficiency, four numerical examples are given.

Highlights

Fault diagnosis of analog circuits is a fundamental problem for design validation [8,10,11]
This section gives the theoretical background of the method proposed for tracing of input–output characteristics in nonlinear circuits comprising bipolar and MOS transistors, having multiple DC solutions
An efficient algorithm for tracing input–output characteristics in circuits having multiple DC solutions is proposed, based on the theory known under the name a linear complementarity problem [5,7]

Summary

Introduction

Fault diagnosis of analog circuits is a fundamental problem for design validation [8,10,11]. A fault can be soft if a parameter is drifted from its tolerance range, but does not lead to any topological changes, or catastrophic which is defined as cut (opencircuit) of some connecting path or short-circuit of some pair of points. Fault diagnosis of nonlinear circuits using SBT approach, based on DC analysis, is considered. The question which of the possible values occurs depends on the transient state which precedes the DC steady state Since it is unknown, all the operating points should be taken into account during fault diagnosis. The crucial point of the proposed approach is tracing a large number of nonlinear multivalued input-output characteristics For this purpose, an efficient algorithm is developed, based on the theory known under the name a linear complementarity problem [5,7,27], considering the deviations of the circuit parameters within their tolerance ranges. Since the method usually needs only one node accessible for measurement it can be applied both to integrated circuits and PCB-based circuitries

The Theoretical Background

The Proposed Algorithm

Circuit Example

The Fault Dictionary

Numerical Examples

Discussion and Concluding