Electronics Forum | Wed Feb 17 13:02:03 EST 2016 | comatose
The layer count itself isn't going to be what drives yields. What is the trace/space? How much annular ring for vias did you give them to play with? Class 2 or class 3? What's the worst hole aspect ratio? Controlled impedance? The closer you run to y
Electronics Forum | Wed Jul 24 17:25:01 EDT 2019 | davef
Your solder stencil design should follow all basic rules for solder stencil design are followed in accordance with IPC-7525 including adherence to an area ratio of 2:3 or greater and an aspect ratio of 1.5 or greater.
Electronics Forum | Thu Mar 18 07:19:39 EDT 2021 | bukas
maybe. some machines require screen aspect ratio of 4:3 as CRTs are 4:3. If you find that 16:9 doesnt work try 4:3 if you have one, they are rare.
Electronics Forum | Thu May 09 17:24:11 EDT 2002 | davef
First, SM-782 elates to surface mount pads. So, expecting to find PTH design rules there is a bit of a stretch. Search the fine SMTnet Archives for similar threads. For instance here�s one from last week: http://www.smtnet.com//forums/index.cfm?fu
Electronics Forum | Sat Mar 31 08:22:42 EDT 2007 | davef
Are you observing stencil design rules with regard to aspect and area ratios? For more: * IPC-7525 - Stencil Design Guidelines * A previous discussion http://www.smtnet.com/forums/Index.cfm?CFApp=1&Message_ID=24848 * Other postings on stencil ratio
Electronics Forum | Tue Jul 31 00:48:55 EDT 2001 | Frank
Sorry I forgot to provide enough information. Stencil thickness is 6 mil Aperture width is 10 mil Aspect ratio (aperture area / wall area) = 0.72 Solder paste mesh size, type 3 (-325 +500) With this aspect ratio we can printing without any probl
Electronics Forum | Fri Feb 15 12:51:30 EST 2013 | emeto
Hi MikeS, I didn't post all the information, because I didn't want to mislead you. I wanted to see your way. We tried 3mil and 4 mil stencil using type 4 paste. It was hard to get the right aspect ratio and that;s why we did it on Nickel stencil - a
Electronics Forum | Mon May 24 13:11:12 EDT 2010 | deanm
A guideline that I use agrees with MikeS: For 20mil pitch, apertures should be 9-10mil with a stencil thickness of 5-6mils to achieve an acceptable aspect ratio of 1.7. Just be sure you are using a mesh Type 3 or 4 solder paste. Otherwise, larger par
Electronics Forum | Mon Nov 13 08:24:03 EST 2000 | G. English
Richard, From your description of the IC, as Wolfgang indicates it sounds like a 20mil pitch device, the aperture design really depends upon your solder paste particle size, we use a type 3 solder paste with a mesh size of �325 / +500microns. This is
Electronics Forum | Tue Dec 17 20:25:13 EST 2002 | iman
Check : 1) design aspect ratio / are ratio required to fabricate the stencil you r using. 2) check if the stencil maker is using your checked aspect ratio / area ratio? if not the same, what are they using? any QA report confirming actual dimension
