EMC Of Automotive Electronic High Voltage Drive Circuit

With the continuous development of IC industry,the feature size of IC is decreasing,and the working environment is becoming more and more complex.The problem of EMC of IC is getting more and more attention.The anti-jamming ability of integrated circuit determines whether it can work normally in complex environment.Intelligent switch chip is an important part of electronic equipment,as switching function to decide whether it normal level after circuit response,switch chip electromagnetic compatibility problems will directly influence the overall work condition of the circuit,and research on the electromagnetic compatibility problem of intelligent switch chip,to improve the anti-jamming ability and reliability of electronic equipment research has important significance.The research object of this paper is an intelligent high-side power switch chip.The structure and function of various protection circuits integrated inside the chip are described.Combined with the internal structure of the chip,the failure mode of the chip under the action of electromagnetic interference is studied.The test platform was built according to the international standard direct power injection method.The EMC test was carried out on the chip,and the experimental results were analyzed.The specific work arrangement is as follows:Firstly,the research background and research process of EMC are introduced,and the experimental equipment,experimental platform and experimental process are described in detail.Then,the parasitic electrical model of the discrete devices in the test equipment was extracted.Based on the internal circuit of the chip,the test model of the chip was improved.The electromagnetic sensitivity of the chip model was simulated by Cadence software,and the simulation results of the anti-interference ability of the chip at different frequencies were obtained.Then,the electromagnetic sensitivity of VDD,IN and GND pins of the chip was tested by the direct power injection method IN two different mode of chip on and off,and the immunity curves of the chip with frequency were obtained.The results show that the chip has the worst anti-interference ability under the interference signal of1MHz?100MHz,and the anti-interference ability is stronger in the high frequency band of 1000MHz?1GHz,and the anti-interference ability is better in the chip open state than in the chip off state.Then the failure mechanism of the chip is analyzed.Starting from the failure mechanism of a single MOS tube under interference,the failure causes of different pins in different modes are analyzed at the circuit level.Finally,the electromagnetic sensitivity test results of the chip are compared with the simulation results,and the reasons for the errors between the simulation results and the test results are analyzed.