Electronics Forum | Fri Jan 22 18:05:44 EST 1999 | David
Could anyone send me equations to calculate controlled impedance of traces on circuit boards. I am most interested in the buried traces in multi layer boards. Thanks, David - piengr@verinet.com
Electronics Forum | Sat Jan 23 15:19:45 EST 1999 | Earl Moon
| Could anyone send me equations to calculate controlled impedance of traces on circuit boards. I am most interested in the buried traces in multi layer boards. | | Thanks, | David - piengr@verinet.com | As one of the first MLB impedance folks on
Electronics Forum | Mon Feb 18 15:20:43 EST 2008 | kennyg
A PCBA contains a couple of parts that are not sealed and can't be water washed. We hand solder these with no-clean after everything else is water washed. The designer says the no-clean residue must be completely removed so that it will not affect
Electronics Forum | Tue Feb 19 08:49:34 EST 2008 | rgduval
Get the ionic specs from your flux manufacturer, and show it to the designer. No-clean flux/solder is supposed to be low to minimal in ionic contamination, which allow the whole no-clean thing. If he needs further proof, you can have the board io
Electronics Forum | Sun Jan 24 06:44:31 EST 1999 | Kallol Chakraborty
| | Could anyone send me equations to calculate controlled impedance of traces on circuit boards. I am most interested in the buried traces in multi layer boards. | | | | Thanks, | | David - piengr@verinet.com | | | As one of the first MLB impedan
Electronics Forum | Mon Feb 18 17:27:13 EST 2008 | jdumont
If the hand soldering is done right and you use little to no extra flux (other than whats in the solder wire) you should be ok. You should still verify with some testing however... You need to make sure any flux used is activated, thus rendered benig
Electronics Forum | Mon Feb 18 17:36:32 EST 2008 | kennyg
I should have mentioned... the only flux we use for the hand soldering is wire-core, no bottle flux. I think it should be a non-issue to leave the activated wire core flux residue. I'm just looking for some way to prove it to the designer.
Electronics Forum | Wed Feb 20 12:22:39 EST 2008 | shrek
KRIKIES, a designer insisting on cleaning no-clean residues! the BLAME-THE-PROCESS bandwagon travels everywhere, me lad!
Electronics Forum | Mon Feb 18 15:47:42 EST 2008 | ck_the_flip
In theory, no clean flux residues are electrically benign...period. Here's a good test. Subject the board to some moisture/humidity, and have your circuit designer ohm-out any areas that may be affected by conductive material. Option B: Have a la
Electronics Forum | Tue Feb 19 09:26:54 EST 2008 | jdengler
The low solids flux that is commonly called no-clean can affect some circuits. We are building a PCB that measures pico amps. The customer required that it be cleaned. We would rather used the low solids and eliminate a step. The customer had
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