Circuit analysis to predict humidity related failures in electronics - Methodology and recommendations

Aim of this paper is to demonstrate the use of circuit analysis to predict humidity robustness of an electronic circuit design. There is a lack of design tools which can predict failures due to humidity, especially the effect of humidity on electrical functionality of circuits. This work provides a methodology for utilising circuit simulation tools to detect humidity related faults associated with a circuit design by using experimentally determined leakage current data or surface insulation resistance using test pattern or model circuits. Simulation of circuits was performed with the experimentally determined SIR value as a parasitic resistance across two nodes of the circuit. Commonly used circuits such as a differential amplifier and a non-inverting comparator were analysed by this methodology. Based on the analysis, circuits with higher humidity robustness have been suggested as examples to demonstrate the effectiveness of this methodology. Finally, the correlation between the properties of the water layer on SIR pattern and actual components was done, which further demonstrates the applicability of the methodology.