Electronics Forum | Mon Feb 19 13:04:17 EST 2001 | billschreiber
The ultrasonic frequency used in today�s stencil cleaners is usually a 40 kHz �sweep� frequency (also used on semiconductors and other sensitive cleaning applications). This frequency is not low enough to cause stencil damage (the lower the frequen
Electronics Forum | Tue Jul 28 02:28:48 EDT 1998 | Bob Willis
The causes for solder on gold are: Paste wash offs Dirty stencils Dirty under stencil cleaning cloths/no solvent Poor handling The most common reason is wash offs when there is a couple of balls left on the tabs and they reflow. With correct profile
Electronics Forum | Mon Oct 22 15:41:39 EDT 2007 | davef
Bruno The real question about your troop using Kester 951 wave solder flux on boards is: how is the flux applied and controlled. See, when you apply this flux with your wave solder fluxer, it is ideally applied in a metered fashion with your fluxer
Electronics Forum | Thu Jan 02 11:35:30 EST 2003 | Richard
Cleanliness test � �Area Grid Arrays�. Evaluation of residues� resistivity in a specific location on the board. (As compared to �Solvent Extract� evaluation.) We are: SMT assembly, using standard �water soluble� process with micro BGAs (example: C
Electronics Forum | Fri Jan 03 12:12:22 EST 2003 | richard
Good day and thanks for your comments Mike, What did I understood from your notes� 1) ROSE test (�extracting solution�) is probably good enough (with good equipment) to penetrate the space under my micro BGA. 2) I should test 2 parallel batches of
Electronics Forum | Wed Oct 06 03:58:25 EDT 1999 | Brian
| | Hi, | | | | Help! Could anyone help to enlighten me on this? | | | | Question: | | | | If I have a CSP/BGA package of size X by Y and the standoff gap between the component and PCB is Z, What is the maximum allowable Y/Z or X/Z that using a n
Electronics Forum | Tue Jan 05 20:29:32 EST 1999 | Steve Gregory
| A question for you all! | | Back in the good old days, we didn't always know how clean was clean. Much has changed. Much hasn't. | | My question concerns cleaning under, through, and around tight spaces. Way back when, we could not clean under 20
Electronics Forum | Wed Jan 06 09:55:22 EST 1999 | Chrys
| | A question for you all! | | | | Back in the good old days, we didn't always know how clean was clean. Much has changed. Much hasn't. | | | | My question concerns cleaning under, through, and around tight spaces. Way back when, we could not clea
Electronics Forum | Tue Oct 12 17:24:27 EDT 1999 | Kevin Ham
| | A question for you all! | | | | Back in the good old days, we didn't always know how clean was clean. Much has changed. Much hasn't. | | | | My question concerns cleaning under, through, and around tight spaces. Way back when, we could not clea
Electronics Forum | Sat Mar 29 08:38:28 EST 2003 | davef
Iman When you talk about your profile, can we assume you're measuring it on the pads of LGA? Profile the solder paste reflow by placing a thermal couple under the component pad, similar to a BGA. On a slight tangent, as with soldering BGA, paste
