摘要
某电子设备在环境试验低温测试过程中,内部电路运行失常,寄存器读写失败。通过大量对比测试、频率扫描、电路原理图和PCB审查和理论分析,最终发现低温导致电源模块开关噪声频率发生偏移,和芯片内部时钟芯片频率重合,且噪声从空间和线路传导上干扰了芯片内部时钟,造成芯片工作异常,无法进行正常的寄存器读写。通过对噪声隔离和滤波临时措施、以及更换电源模块的整改措施,有效解决了干扰问题,为类似问题的处理提供参考借鉴。
This document describes the situation where the internal circuits of the electronic equipment operate improperly and the register fails to be read or written during the low-temperature test.Through a large number of comparative tests,frequency scanning,circuit schematic diagrams,PCB review,and theoretical analysis,it is finally found that the switching noise frequency of the power module is shifted due to low temperature,which coincides with the frequency of the clock chip inside the chip.The noise interferes with the internal clock of the chip from space and line conduction,causing the chip to operate abnormally and cannot read or write registers normally.Temporary noise isolation and filtering measures and long-term power module replacement measures can effectively solve interference problems,providing reference for similar problems.
作者
张本军
欧阳玉叶
Zhang Benjun;Ouyang Yuye
关键词
低温
开关噪声
干扰
隔离
滤波
low-temperaturet
switching noise
interference
isolation
filtering