| The application field of electronic information equipment is constantly expanding,its working environment is becoming increasingly extreme.It is often faced with harsh environmental factors such as high temperature and radiation.As an important part of electronic information equipment,the smart switch chip’s electromagnetic sensitivity in complex environments directly affects whether the system can operate normally.Affected by the combined stress of electromagnetic and temperature,the drift of the sensitivity threshold of the smart switch chip will cause problems such as the subsequent circuit response error,resulting in the instability of the overall system performance.Therefore,the research on the influence of temperature change on the EMC performance of smart switch chip is helpful to improve the anti EMI ability and reliability of electronic information equipment.Aiming at a smart power switch chip,the influence of temperature on its conduction sensitivity in electromagnetic compatibility performance was studied from the perspective of theory and experiment.By analyzing the components and circuit structure of the smart switch chip,the failure mode of the smart switch chip under the influence of electromagnetic interference is studied.Based on the direct power injection method,an experimental platform for temperature effects of electromagnetic sensitivity is established to test the electromagnetic The effect of combined stress with temperature on the switch chip is analyzed and the experimental results are analyzed.The specific work of the thesis is as follows:Firstly,the background of the research on the electromagnetic compatibility of integrated circuits,the development history of smart power switches and the structure of their protection circuits are introduced,and the mechanism of the voltage comparator in the protection circuit being interfered by RF signals is analyzed.Then,the electromagnetic sensitivity of the smart switch chip is studied.Based on the electrical characteristics of the MOS tube,its principle of interference by radio frequency signals was analyzed.The electromagnetic sensitivity test of the direct power injection method was performed on different modes and pins of the sample chip,and the test results under different modes and pins were performed.analysis.The results show that the chip has the worst immunity in the range of 1 MHz to 100 MHz,and in the high frequency band,the immunity gradually increases with the increase of frequency.Under different operating modes,the overall chip immunity is lower in PWM mode;among different pins,the Vbb pin has higher immunity.Finally,the temperature effect of the electromagnetic sensitivity of the smart switch chip was studied.Based on the electrical and temperature characteristics of the MOS tube,the influence of temperature effect on the electromagnetic sensitivity of the switch chip under different failure conditions is analyzed,and the Vbb pin and the IN pin of the chip are tested through the test platform of the electromagnetic sensitivity temperature effect.The results show that the electromagnetic sensitivity of the Vbb pin and the IN pin will have different changes under the influence of temperature. |
