Analogue fault detectability comparison between power supply current and output voltage magnitude and phase spectrum components

A method using magnitude and phase spectrum components for fault detection of catastrophic and parametric faults is presented. A procedure is developed, discrimination factors are defined and their values are adjusted to include circuit parameter deviations. Comparative results from linear and nonlinear configurations of operational amplifier circuits are given, showing a significant increase in fault detectability over a previous method and also an improvement in fault coverage by the use of the power supply current against the output voltage signal.