1
完善资料让更多小伙伴认识你,还能领取20积分哦, 立即完善>
嗨!
我们有一些不稳定的元件,例如电容器*“pF”*和电阻器*“M Ohm”*。 您是否有任何提示可以让这种类型的组件更稳定? 有谁知道如何做这样的事情,在调试行中结合多个测试,以便更有可能测试该组件? 以上来自于谷歌翻译 以下为原文 Hi!! We have some unstable components, for example, capacitors *"pF"* and resistors *"M Ohm"*. Do you have any tips to be able to leave this type of component more stable? Does anyone know how to do something like this to combine more than one test in debug line to have more of a possibility of testing for that component? |
|
相关推荐
2个回答
|
|
Leo,这不是一个容易回答的问题。
测试可能不稳定的原因有很多。 我将尝试列出一些供您考虑的因素... 1)夹具 - 被测电路板是否保持稳定状态? - 探针接触是否一致? - 顶盖是否一直将电路板推到探头上? 每次吸收电路板时,探头行程是否一致? - 绕线紧紧缠绕在p型引脚上? 2)测试仪 - 测试人员是否一直工作? - 自动调整后诊断程序是否通过了所有测试? - 进入测试仪的电源是否稳定且干净? 相邻SMT机器没有引起地面尖峰? - 你的MINT针脚有污染吗? 3)被测电路板 - 电路板上有很多焊剂吗? - 组件供应商是否有变化? 4)测试 - 您使用的是正确的ASRU范围(“ar”)吗? - 你使用的是正确的“重新”吗? 理想情况下,应设置“re”,使得测量运算放大器(MOA)的增益为“1”。 - 您使用3线或4线测量吗? - 3根或4根电线来自4个不同的探头,每个探头都有自己的测试点? - 电容器是否连接到IC? ...... IC供应商有变化吗? ... IC有内部电容或阻抗,可能会影响您的测试。 这些阻抗可能是不同的供应商。 - 您是否尝试过防护隔离被测设备? 您获得不同值的一个原因是您的测量电路中存在漏电流且漏电流不一致。 您需要最大限度地减少漏电流。 - 最后,您的测试限制是否设置得太小? 如果组件是20%组件,则不应将测试限制设置为20%。 至少应设置为25%或30%以允许生产容差。 我希望这有帮助。 以上来自于谷歌翻译 以下为原文 Leo, This is not an easy question to answer. There are many reasons why the tests can be unstable. I will try to list out some of the factors for your consideration ... 1) Fixturing - Is the board under test held in a stable condition? - is the probe contact consistent? - is the top cover pushing the board onto the probes consistently? The probe travel is consistent each time the board is sucked down? - the wire wrapping is tightly wound around the p-pins? 2) Tester - is the tester working consistently? - Diagnostics is passing all tests after Autoadjust? - the power into the tester is stable and clean? No ground spikes induced from adjacent SMT machine? - is there contamination on your MINT pins? 3) Board under test - is there lots of flux on your board? - was there a change in component vendors? 4) Test - Are you using the correct ASRU range ("ar")? - Are you using the correct "re"? The "re" should ideally be set such that the gain of the Measurement Op Amp (MOA) is "1". - Are you using 3 or 4 wire measurements? - The 3 or 4 wires come from 4 different probes, each having their own testpoint? - is the capacitor connected to an IC? ... Is there changes to the IC vendor? ... ICs have internal capacitors or impedance which can affect your test. These impedance may be different amonst vendors. - Have you tried guarding to isolate the device under test? one reason why you get different values is because there is leakage current in your measurement circuit and this leakage current is not consistent. You need to minimise this leakage current. - Finally, are your test limits set too small? if the component is a 20% component, you should not set your test limits to 20%. At minimum, you should set at 25% or 30% to allow for production tolerance. I hope this helps. |
|
|
|
看到提到高价值电容和低值电阻测试可靠性引起了我的注意。
还有一些需要考虑的因素,如果这是一个使用导向探针的相对较新的夹具,并且在顶板上还有一个抗静电层 - 您可能会看到整个抗静电层的平行电阻。 开车送我疯了,现在我指定固定装置,在导向探针通孔处铣削顶板抗静电层。 以上来自于谷歌翻译 以下为原文 Seeing mention of high value caps and low value resistor test reliability got my attention. Something else to consider, if this is a relatively new fixture using guided probes and also has an anti-static layer on the top plate - you may be seeing parallel resistance across the anti-static layer. Drove me crazy, now I specify fixtures to have the top plate anti-static layer spot milled at guided probe through holes. |
|
|
|
只有小组成员才能发言,加入小组>>
1279 浏览 0 评论
2371 浏览 1 评论
2187 浏览 1 评论
2061 浏览 5 评论
2945 浏览 3 评论
1099浏览 1评论
关于Keysight x1149 Boundary Scan Analyzer
748浏览 0评论
N5230C用“CALC:MARK:BWID?”获取Bwid,Cent,Q,Loss失败,请问大佬们怎么解决呀
917浏览 0评论
1279浏览 0评论
小黑屋| 手机版| Archiver| 德赢Vwin官网 ( 湘ICP备2023018690号 )
GMT+8, 2024-12-21 16:11 , Processed in 1.541390 second(s), Total 78, Slave 62 queries .
Powered by 德赢Vwin官网 网
© 2015 bbs.elecfans.com
关注我们的微信
下载发烧友APP
德赢Vwin官网 观察
版权所有 © 湖南华秋数字科技有限公司
德赢Vwin官网 (电路图) 湘公网安备 43011202000918 号 电信与信息服务业务经营许可证:合字B2-20210191 工商网监 湘ICP备2023018690号