Distributed Heat Testing And Analyzing For Circuit Card Assembly

The thermal reliability of CCA is one important factor of established reliability to electronic equipment. The thermal reliability research have two main aspects : testing the distributed heat by multi-temperature measure instrument and the thermal analysis in the assistance of CAE software. Based on the research of present situation and main problems of the temperature measure instruments, in this dissertation a suit of temperature testing system based on 1-wire digital thermometer is designed first to get distributed heat and the hottest spots of the electronic components ,at the same time it can provide necessary basis for the thermal analysis and the thermal design of electronic equipment. The FEA software ANSYS is applied to analyze the heat distributed of some heat-sensitive components in a certain intelligent Car Windows ECU due to its defects in thermal reliability when it works. The key question of the research is how to deal with boundary condition of the model. Once the bug of thermal design is found , the optimal thermal design is carried through in succession, the hot spots temperature of the PCB is fell and the reliability of intelligent Car Windows ECU is improved greatly.Through modeling, ensuring the boundary condition and FE analysis of Car Windows ECU, distributed heat is gained and at the same time we make use of the distributed heat testing system designed by ourselves to collect the data of the corresponding spot, The result shows that they could be matched properly. It validates the modeling of ECU pcb and indicates that the design of distributed heat testing system achieves our anticipative aim. The research on thermal reliability of CCA is finished satisfactorily.