Analysis And Control On The Vibration Of Printed Circuit Board Assembly

As an indispensable part of the structural design of electronic equipment, the analysis and control for vibration of Printed Circuit Board Assembly (PCBA) are extremely important. Based on the theory of mechanical vibration and Finite Element Method (FEM), this paper analyzes the dynamic property, response and reliability of a PCBA. In the light of the analysis, some optimizing control methods of vibration of the PCBA are studied.In this thesis, several ways to establish the FE model for PCBA are discussed; the FE model of PCBA is set up and proved to be true. Using the module of dynamic analysis in ANSYS, in order to get parameters of dynamic characteristics and kinetic response of the PCBA, a series of research is processed, including the modal analysis, the harmonic analysis, the impact analysis and the Power Spectral Density (PSD) analysis. Then, applying the Poisson Formula and the modified Poisson Formula, the dynamic reliabilities of the PCBA excited by a random vibration source are calculated. And the fatigue damage of one spot weld is also worked out.After contrasting three methods of installation used generally for PCBA, a new way with pre-stressed force is put forward, and its effectiveness in controlling the vibratory response is verified. According to the differences among the four methods of installation, some problems are summarized in this paper when we choose the methods of installing PCBA and positioning electronic devices on PCB, some helpful suggestions are also given in the text. Finally, an inbuilt rubber damper is designed to absorb the energy passed from the base. The results show that the damper can control the response of displacement and stress and also reduce the response of acceleration obviously.