Electronics Forum | Sat Dec 04 09:23:20 EST 1999 | Christopher Lampron
Kantesh, Does this particular part have a heat sink across the bottom side of the component and does your pad size and stencil aperture match the component? I have just had a very similar problem with a DPAK. What we found was that the recomended pad
Electronics Forum | Sat Dec 04 09:42:18 EST 1999 | Chris McDonald
Just as explained in a follow-up you are getting too much paste on the pad. The pad is probably the right size but you cant have your aperature the same size as your pad. What we have done is put a Cross in the stencil. This will reduce the paste and
Electronics Forum | Mon Dec 06 17:50:39 EST 1999 | Kantesh Doss
Christopher: Thank you for sharing your experience about the DPAK. Yes, out part has a heat sink at the bottom. Our stencil opening was 7 mils (in both X and Y) smaller than the pad size excepting that the stencil opening consisted of a series of zeb
Electronics Forum | Thu Dec 02 23:43:23 EST 1999 | Kantesh Doss
We have a serious misalignment problem of D-Pak components (Specifically Motorola's part number MJD-3055/MJD-2955)following reflow soldering process. We are using Alpha Metals UP78 solder paste. Our reflow oven is Nitrogen inerted and our oxygen leve
Electronics Forum | Fri Apr 30 07:39:54 EDT 2010 | jdengler
We do a similar part on a Fuji IP3. Set table speed to low. I do not know the QP, but if it's similar to the IP make sure the board clamp/unclamp is smooth. On our IP it got dirty and was jerking causing the board to jump a little which bounced ou
Electronics Forum | Sun May 02 11:36:27 EDT 2010 | jdeluna
I do agree with Jerry: you should apply more paste on it, either with a step stencil, or doing overprint on it by, let's say 120% on Transformer's pad. Also, you need to check : a) there's smooth movement on transport process after the placement, no
Electronics Forum | Wed May 05 15:27:06 EDT 2010 | bradlanger
Make sure that both lead frames are contacting the PCB pads when the part is on the placement head. We had an SM xfrmer that we were handling with vacuum by a ferrite cap that was not glued on straight. The part would contact one set of pads and get
Electronics Forum | Fri Dec 10 10:25:59 EST 1999 | Wolfgang Busko
Hi Larry, you might find something looking for the thread "D-Pak misalignment Problem - Kantesh Doss 23:43:23 12/02/1999" Good luck Wolfgang
Electronics Forum | Fri Sep 13 13:51:38 EDT 2002 | kenbliss
I recently saw an ad in a major trade magazine that stated: �about 60%of all printed circuit board manufacturing defects are due to stencil printing� I would like to hear comments from people that are running SMT lines, is this fact and if it is, w
Electronics Forum | Mon Jul 24 08:30:25 EDT 2006 | nodlac
- Dirty stencil transfering paste from the stencil bottom. - Stencil opening (Pad Hole) to pad ratio incorrect - too large -misaligned stencil
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