Electronics Forum | Thu Nov 07 12:35:38 EST 2002 | slthomas
Sounds like you're talking about the "heel" of the lead not being soldered, in other words, no heel fillet, which IS necessary. That problem, for us, was attributed primarily to poor layout (insufficient length of pad extension to provide room for
Electronics Forum | Mon Mar 26 20:55:16 EST 2001 | davef
Two things: 1 IPC pad calculator is an excellent resource for you and your board layout staff. Consider that working together with the calculator may allow you both an opportunity to balance your interests. 2 It's unlikely that the ceramic parts h
Electronics Forum | Thu Jan 24 04:54:43 EST 2002 | wbu
Well Greg, I don�t know YOUR 0805 Pads but if you look at the recommended pattern for 0805 in IPC-SM-782 you might notice that the Z-dimension is somewhat about the size of your 1206 part length. With that and assuming that you ask if the results wi
Electronics Forum | Sat Feb 05 14:51:08 EST 2000 | Bill Petlock
Casimir, The Q and other lead trimmers work extremely well if properly used. Blade life is directly proportional to to the height of the cut. There are a few factors that are very important in trimming. You are working with a solid carbide blade whi
Electronics Forum | Wed Mar 29 22:30:13 EST 2000 | cklau
Hi guys; There are a few points that should be taken in to considerations regarding IPC-SM-782 land pattern and design rules. As a general rule all SMT reflow pattern should be in comply with SM-782 but however for special cases like : * PLCC land
Electronics Forum | Thu Aug 05 05:23:13 EDT 2004 | Bryan
Hi All,per my understanding ,the fail mode is the heel fillet of QFP seems no good,right?If yes...I think..we should:1.increase the aperture length on stencil and make sure there's enough solder paste on pad before reflow. or you can increase your t
Electronics Forum | Wed Apr 06 11:10:47 EDT 2005 | smt_rookie
We process a double-side reflow board (10 ups). Chips and IC's on the bottom side while chips, IC's plus thru-hole connectors and IC sockets on top side (bottom side first then top side reflow). In the past, we were not encountering any soldering pro
Electronics Forum | Sun Apr 21 19:56:57 EDT 2002 | francis khoo
Hello Pete, Very true about the heel fillet. Looks like the pad at pcb has to be designed such that the pad should extend at heel but short at toe. About the encapsulation. I can understand the requirements. Can you provide me with a more detail proc
Electronics Forum | Sat Feb 05 09:13:39 EST 2000 | Dave F
Hany: In response to your questions: 1- In a double wave solder M/C, is possible to completely eliminate the second wave without affecting the quality of the solder joints? Many w/s machines have a turbulent wave and a smooth wave. The turbule
Electronics Forum | Fri Nov 09 11:55:49 EST 2001 | mparker
If you are getting solder shorts under a device, how would "hiding" the extra long pad with solder mask help? If the pad can't be seen once the device is in place, it is already "hidden". Getting your customer to redesign the pads may take some time
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