Electronics Forum | Mon Apr 28 09:34:37 EDT 2003 | davef
Double sided weight of component to total pad mating area ratio: 30 gm per sq inch (50 mgm per mm2) Go to the sites of these consultant-people for additional background [I'm not sure exactly where on these sites to look, but both are laden with goo
Electronics Forum | Fri Jul 24 13:41:05 EDT 1998 | Bob Willis
Sorry guys have a look at this list of component weights and then work out the surface area of the lead/pad and then come back on the PLCC issue. Chip 0805���� 0.007g������ 2 Chip 1206���� 0.009g���� 2 Chip 1210���� 0.012g���� 2 SOT23���������0.008g�
Electronics Forum | Thu Feb 07 09:07:10 EST 2002 | fmonette
Dason, Please be aware that weight gain is only a very crude estimate of the component moisture content. This is only accurate when the moisture is uniformly distributed inside the component (which is actually never). This measurement is usually no
Electronics Forum | Mon Dec 11 03:46:14 EST 2000 | JohnW
I have to say I've never heard of anything tombstoning over wave, I've seen issues where the glue dot is too high or off to one side creating a poorly seated component that has too big a gap between pad and endcap(and hence an open), but never a tomb
Electronics Forum | Thu Nov 18 19:45:26 EST 1999 | Deon Nungaray
Deon Response: Hello Will, Yes, you can reflow a double sided board using 63/37 solder paste on both sides. There are some limitations as far as the mass of the components to reflow the second time. If you have doubts or are concerned that a compone
Electronics Forum | Sat Nov 16 21:19:37 EST 2002 | MA/NY DDave
Hi, An interesting tread, Neat reading. Just pulled out a guide that was given at Nepcon West2000 entitled: Nepcon West 2000 Pick & Place Evaluation You might want to call them to get a copy of the report. As two or three others already pointed
Electronics Forum | Thu Jun 28 15:22:59 EDT 2012 | spitkis2
Would like to ask end users or those with experience using infra red rework equipment (specifically when the top heater is IR) the following: 1. Can you successfully rework Package On Package (PoP) type devices? With heat directed through the packa
Electronics Forum | Fri Mar 02 09:08:25 EST 2007 | samir
There is a formula that determines whether a component will fall off during a 2nd reflow. It takes into account the grams (weight) of the component and the total surface area of the solder joints. I don't know this off the top of my head, but it's
Electronics Forum | Mon Feb 25 08:14:04 EST 2008 | adetuc
Hi ... We use DRS24C Air-Vac machines for placing BGA devices, and have been having problems with shorts on corners of one device in particular, its a PBGA and its size is 4.5cm square and 15grams weight. When the component is picked up and the com
Electronics Forum | Sat Feb 20 20:24:40 EST 2021 | sync40
Hello Ameen, It is needed a moderate impact bump to generate skew. Even blowing of the fans generally cannot generate serious skew -unless the pads apertures are not suitable for the components size/weight. You can try for yourself. Take a board wi
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