Electronics Forum | Thu Feb 04 06:50:35 EST 1999 | Greg Flynn
What allowances are people using out there for components off-pad, we currently use 50% of lead width without breaking trace/component clearances but we have a customer demanding 25% allowance ?
Electronics Forum | Thu Feb 04 09:09:11 EST 1999 | Peet
| What allowances are people using out there for components off-pad, we currently use 50% of lead width without breaking trace/component clearances but we have a customer demanding 25% allowance ? | We use 50% for civile application, and 25% for mil
Electronics Forum | Thu Feb 04 21:17:41 EST 1999 | Chris G.
| What allowances are people using out there for components off-pad, we currently use 50% of lead width without breaking trace/component clearances but we have a customer demanding 25% allowance ? | IPC states: 50% off pad for class 1 and 2 25% off
Electronics Forum | Wed Jun 21 13:06:02 EDT 2006 | grantp
Hi, If your worried about them being lead free components, because it's "not clear" then you should be able to ask the manufacture of them if they are lead free, as they normally trace the batch code, and manif date and will know for sure. Most pas
Electronics Forum | Thu Aug 10 14:52:08 EDT 2006 | russ
Should be some numbers on the top of the other two. If you can read them we can get you the right part info. it also looks as though you have some trace and pad damage that will require repair prior to you putting down new part. Or you can remove
Electronics Forum | Mon Jul 18 12:24:53 EDT 2016 | oleksz
Some people involved in PCB assembly process claim that SMD components reflow soldering problems are often caused by traces running under a component. According to this claim, trace (or any copper) covered by solder mask and placed under SMD componen
Electronics Forum | Mon Jul 18 12:25:30 EDT 2016 | oleksz
Some people involved in PCB assembly process claim that SMD components reflow soldering problems are often caused by traces running under a component. According to this claim, trace (or any copper) covered by solder mask and placed under SMD componen
Electronics Forum | Tue Jul 19 11:52:24 EDT 2016 | oleksz
Thank you Pavel. Aleksander
Electronics Forum | Tue Jul 19 08:26:46 EDT 2016 | pavel_murtishev
Aleksander, The answer is no. Solder deposit being printed is 80um-150um in height depending on PCB design what is two times higher than any track covered by solder mask. Molten solder will merely center the component. QFNs are prone to soldering
Electronics Forum | Mon Nov 26 13:09:20 EST 2007 | realchunks
Even a slight amount of epoxy will prevent a part from soldering. Look at the part after print. If you any trace of you epoxy between the pad and part, you have a potential problem.
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