Electronics Forum | Fri Jun 20 03:47:24 EDT 2008 | philip
Hi all, any good recommendation for PbF paste application to reduce voids underneath the QFN thermal pad (stencil thickenss? opening? via hole? reflow profile etc)? We have tried few stencil opening design but no significant improvement as seen. Ther
Electronics Forum | Thu Dec 08 22:56:07 EST 2005 | davef
Questions are: * Is the stencil design proper to provide the correct amount of solder paste? * Is the stencil design proper to provide for release of solder paste? * Is solder paste filling the stencil aperatures, prior to separation? * Are stencil a
Electronics Forum | Tue Apr 13 08:25:15 EDT 2004 | arcandspark
I would have gone to a .004" stencil but again, the board designers, which we have no control over or are we allowed to give input to, have made the pads on all connectors and many other parts so small that we are almost seeing insuffecient solder us
Electronics Forum | Fri Jun 10 09:02:58 EDT 2005 | ktron
Hi Guys.. Does anybody had experienced with designing the stencil for Right Angle LED without any dewetting problem on the LED termination? Currently our stencil opening is 1:1 and we still got so high reject due to this problem. Pls Advise, thanks
Electronics Forum | Tue Aug 12 07:35:23 EDT 2008 | stevezeva
Hi, Is the footprint per the component manufacturers recommendations? The reason I ask is because it kinda looks like the pads are extending beneath the component. Could cause the part to float up on top of the solder and not allow the leads to wet
Electronics Forum | Fri Sep 11 00:56:44 EDT 2020 | rsatmech
Thanks for your inputs. Soak - 120 to 180 at average 110sec Paste - Senju - S70G - Type 5 (also suspect paste chemistry yet it's customer defined I can't do anything about this) N2 - maintaining O2 PPM at 1000 Stencil - planning to reduce the stenci
Electronics Forum | Thu Feb 24 11:05:53 EST 2000 | Russ
I usuallly like to have the pad size the same size as the ball up to +2mil, the pcb solder mask opening to be +4 mil from the pad size (I have found this to aid in Xray inspection for opens since you can see the little tail of the solder wicking up t
Electronics Forum | Thu Jan 02 22:09:15 EST 2020 | Zack
Hello, Can you give more detail on LGA parts in question? is 50 mm x 50 mm is overall size of the parts? What about pad pitch and how big is the pads individually? I assume that 50x50 mm is overall size. How about the stencil opening for the LGA pad
Electronics Forum | Wed Aug 09 15:01:53 EDT 2023 | davef
Consider opening the stencil aperture to increase the amount of solder available to the connector leads.
Electronics Forum | Thu Nov 29 22:38:05 EST 2007 | shy
Hi Dback, Yes, i'm open "dog bone" aperture for my chip component. this is to prevent solder ball issue. For fine pitch i'm opening square with full length and half width to prevent bridging. Btw, if "dog bone" is not for chip component, what is your
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