终于轮到我了，苍天饶过谁！

[{"insert":"#测试技巧分享#\n"},{"attributes":{"color":"#000000"},"insert":"大家好，我是工程师看海，原创文章欢迎"},{"attributes":{"color":"#000000","bold":true},"insert":"点赞分享！"},{"insert":"\n"},{"attributes":{"color":"#000000"},"insert":"说来惭愧，一些朋友可能知道，我前两天烧了一个运放，哦，不对，是两个。"},{"attributes":{"align":"justify"},"insert":"\n"},{"attributes":{"color":"#000000"},"insert":"当时的需求是做双通道信号放大，每通道有两级放大，我选了个以前使用过的宽电源运放，搞定原理图后，交给朋友拉线、打板验证，朋友打板焊接后临时有事，就交由我来测试现场环境下的效果。"},{"attributes":{"align":"justify"},"insert":"\n"},{"attributes":{"color":"#000000"},"insert":"朋友把板子给我之前，确认过双通道都工作正常，这是工作交接的重要过程之一，要保证交接内容的稳定可靠，或者要清楚还存在着哪些问题。"},{"attributes":{"align":"justify"},"insert":"\n"},{"attributes":{"color":"#000000","bold":true},"insert":"但是！"},{"attributes":{"align":"center"},"insert":"\n"},{"attributes":{"color":"#000000"},"insert":"但是我刚上电测试就发现，其中一个通道无法正常工作，经过定位后锁定问题为通道一的第二级运放失效，再次和朋友确认，他之前测试一切正常，要记住这个细节！"},{"attributes":{"align":"justify"},"insert":"\n"},{"attributes":{"color":"#000000"},"insert":" "},{"insert":{"image":"https://community-1252773949.cos.ap-guangzhou.myqcloud.com/article/2033/cdaca4dbd3653192.png"}},{"attributes":{"align":"center"},"insert":"\n"},{"attributes":{"color":"#000000"},"insert":"天气转冷，空气干燥，开始有静电了，手被“啪”了几次。"},{"attributes":{"align":"justify"},"insert":"\n"},{"attributes":{"color":"#000000"},"insert":"然后没过几分钟，通道2的第二级运放也挂了。。。。。。。"},{"attributes":{"align":"justify"},"insert":"\n"},{"attributes":{"color":"#000000"},"insert":" "},{"insert":{"image":"https://community-1252773949.cos.ap-guangzhou.myqcloud.com/article/2033/34ae75339cd85252.png"}},{"attributes":{"align":"center"},"insert":"\n"},{"attributes":{"color":"#000000"},"insert":"这可要高度警惕，为什么第二级会坏呢？"},{"attributes":{"align":"justify"},"insert":"\n"},{"attributes":{"color":"#000000"},"insert":"结合上面的背景，双通道刚开始都是好的，到我手里后，1通道的第二级就是坏的，一段时间后2通道的第二级也坏了，猜测很可能是某个参数过应力导致器件异常。"},{"attributes":{"align":"justify"},"insert":"\n"},{"attributes":{"color":"#000000"},"insert":"中间有静电“啪”了几次，是静电吗？"},{"attributes":{"align":"justify"},"insert":"\n"},{"attributes":{"color":"#000000"},"insert":"应该不是，这个运放用了好久了，其他项目没有发生过静电问题。"},{"attributes":{"align":"justify"},"insert":"\n\n"},{"attributes":{"color":"#000000"},"insert":"是电源吗？一般遇到问题优先考虑电源。"},{"attributes":{"align":"justify"},"insert":"\n"},{"attributes":{"color":"#000000"},"insert":"测量下电源都正常工作。"},{"attributes":{"align":"justify"},"insert":"\n"},{"attributes":{"color":"#000000"},"insert":" "},{"attributes":{"align":"justify"},"insert":"\n"},{"attributes":{"color":"#000000"},"insert":"是过压吗？"},{"attributes":{"align":"justify"},"insert":"\n"},{"attributes":{"color":"#000000"},"insert":"应该不是，我记得运放供电范围还是挺高的，电源过压是个低级的错误，应该不是。"},{"attributes":{"align":"justify"},"insert":"\n"},{"attributes":{"color":"#000000"},"insert":" "},{"attributes":{"align":"justify"},"insert":"\n"},{"attributes":{"color":"#000000"},"insert":"此时我留意到电源的输出电流，刚开始是5ma，现在变成了10ma，我们在设计电路的时候一定要对系统工作电流有个概念，比如手机关机一般是uA级别，待机一般是mA级别，开机过程中会达到A级别。"},{"attributes":{"align":"justify"},"insert":"\n"},{"attributes":{"color":"#000000"},"insert":" "},{"insert":{"image":"https://community-1252773949.cos.ap-guangzhou.myqcloud.com/article/2033/c6c6be95c80f900b.png"}},{"attributes":{"align":"center"},"insert":"\n"},{"attributes":{"color":"#000000"},"insert":"电流增加，是器件坏后漏电，还是看下供电电压吧，难不成真是过压？"},{"attributes":{"align":"justify"},"insert":"\n"},{"attributes":{"color":"#000000"},"insert":"然后默默打开了手册，"},{"attributes":{"color":"#000000","bold":true},"insert":"±3.5V"},{"attributes":{"color":"#000000"},"insert":"几个大字映入眼帘。而我给的是±5.0V。"},{"attributes":{"align":"justify"},"insert":"\n"},{"attributes":{"color":"#000000","bold":true},"insert":"大意了！！"},{"attributes":{"align":"center"},"insert":"\n"},{"attributes":{"color":"#000000","bold":true},"insert":" "},{"insert":{"image":"https://community-1252773949.cos.ap-guangzhou.myqcloud.com/article/2033/bbf89277c2db9b49.png"}},{"attributes":{"align":"center"},"insert":"\n"},{"attributes":{"color":"#000000","bold":true},"insert":"不断地提醒别人，器件选型应用，一定要先看电压范围，终于，轮到我了，苍天饶过谁！"},{"attributes":{"align":"justify"},"insert":"\n"}]