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This paper introduces a typical corrosion phenomenon of the Integrated Circuits. A three-terminal adjustable shunt regulator outputted abnormal voltage on a PCBA because its Vref pin was open. Bonding pad corrosion was confirmed by SEM&EDX analysis. The pad was electrical open to the surrounding schematic. After a whole investigation, several lots of wafers were confirmed to be contaminated by silicone oil which was introduced during the demolding process. Delamination occurred between the molding compound and die. Plating solution which contained chlorine and sulphur percolated into package during Tin Plating.Supplier of the regulator was recommended to improve the demolding process. Besides, routine reliability monitoring(such as C-SAM, HAST) can be executed in quality control process to eliminate this failure mode in customer’s application.

The heavy use of air-core reactors led to sharp increase of electromagnetic pollution, threating the health of working staff and the normal operation of other electric equipment. Therefore, it becomes important to study the EMI (Electromagnetic Interference) between air-core reactors. Firstly, the small-scale model of the air-core reactor is made based on the scaling rules. Then, the different regular arrangements in the actual installation of air-core reactors are simulated by changing the position of the small-scale models. At last, the MF (Magnetic Field) of air-core reactors is analyzed according to the model. Thus, it is possible to study the MF distribution of different arrangements of air-core reactors by establishing some-small scale models. The study of the paper provides reference for the practical application of air-core reactors in substation.

Some large-sized electrical equipment of the power system has been approximately simulated by the equivalent small-scale model. And the method has great practical value in the power system simulation and scientific study. However, the common small-scale model of reactors can't simulate the EMI (Electromagnetic Interference) for other electrical equipment just because of only taking electrical parameters such as its impedance into consideration. In this paper, the simplified model is made to simulate the PFMF (Power-frequency Magnetic Fields) around air-core reactors. The model provides theories and technologies for the forecast of PFMF around air-core reactors. Besides, the optimal structures of bicyclic and tricyclic simplified models are made by analyzing small-scale experiments and simplified models. And the annlytical result is verified by making models in the laboratory.