Fatigue Life Estimation of Components Mounted on PCB Due to Vibration

摘要

A spacecraft consists of a number of electronic packages to meet the functional requirements. An electronic package is generally an assembly of printed circuit boards placed in a mechanical housing. A number of electronic components are mounted on the printed circuit board (PCB). A spacecraft experiences various types of loads during its launch such as vibration, acoustic and shock loads. Prediction of response for printed circuit boards due to vibration loads is important for mechanical design and reliability of electronic packages. Dynamic analysis of printed circuit boards is carried out using finite element method. The components mounted on PCB experience stresses due to curvature of the board and inertia loads. The response of the component depends on its natural frequency as well as PCB dynamic characteristics. The objective of this paper is to predict the fatigue life of components mounted on printed circuit boards due to vibration. A case study of a typical component mounted on PCB is taken up and dynamic analysis is carried out for base excitation. Modal analysis and frequency response analysis are carried out using FEM. The component lead stresses due to vibration are determined. The fatigue life is estimated for sine and random vibration environment.