A Tolerance Design Method for Electronic Circuits Based on Performance Degradation

Due to the effects of manufacturing tolerances and environmental conditions, component parameters vary and degrade with time. This may cause performance measures of electronic circuits to deviate from design specifications. Therefore, a tolerance design method based on performance degradation is proposed for electronic circuits, so as to improve the robustness of output characteristics. First, sensitive components causing output fluctuation are determined via orthogonal experiment and PSpice simulation. Then, degradation path models are established to describe the degradation process of sensitive components. The predicted values worked out by the degradation path models are substituted into the simulation model for Monte Carlo analysis. Besides, output characteristics and performance reliability are evaluated according to Monte Carlo simulation. Finally, optimum allocation is carried out for component tolerances as per minimum life cycle cost. The proposed method is illustrated by a case study of light‐emitting diode (LED) driver. Copyright © 2013 John Wiley & Sons, Ltd.