A Unified Procedure for Fault Detection of Analog and Mixed-Mode Circuits Using Magnitude and Phase Components of the Power Supply Current Spectrum

A method using the power supply current for fault detection in analog and mixed-mode circuits is presented. A new unified fault detection procedure is introduced, and its fault detection capability is estimated. The procedure combines the rms value and the magnitude and phase components of the power supply current. Certain required discrimination factors are defined, and their values are adjusted to include circuit parameter deviations and matching dependencies for the efficient application of the method. Representative results from the simulation of an operational amplifier (opamp) and a flash analog-to-digital converter circuit are given, showing the effectiveness of the proposed method.