278 ground and planes results

Electronics Forum: ground and planes (Page 6 of 28)

BGA Shorting problem

Electronics Forum | Mon Aug 31 22:30:09 EDT 1998 | Kelly Morris

We are experiencing shorting on a BGA. The part has a 1mm pitch with a 196 I/O count. The problem seems to pop up without warning & disappear in the same manner. Our pad design is .020" diameter pads with .025" solder resist diameter. The center

Re: BGA Shorting problem

Electronics Forum | Tue Sep 01 19:16:51 EDT 1998 | Kallol Chakraborty

| We are experiencing shorting on a BGA. The part has a 1mm pitch with a 196 I/O count. The problem seems to pop up without warning & disappear in the same manner. | Our pad design is .020" diameter pads with .025" solder resist diameter. The ce

Re: BGA Shorting problem

Electronics Forum | Tue Sep 01 02:50:40 EDT 1998 | karlin

Wave soldering PWB with foil surface.

Electronics Forum | Thu Apr 25 18:32:25 EDT 2002 | Shawn

What he is talking about when he said "foil" is the top and bottom side of the board has a layer that is like a ground plane with no solder resist covering it. It is etched out around the pads that no not need a connection and have a small bride or t

Conformal Coat Thickness

Electronics Forum | Mon Jul 23 17:49:04 EDT 2007 | davef

We know nothing of DeFelsko, but do understand how they distinguish between the solder mask and the conformal coat. DeFelsko manufactures hand-held, non-destructive coating thickness gages that are ideal for measuring the dry film thickness of confo

QFN84 Solder Printing Issue (QFN with Inner LGA Pad)

Electronics Forum | Fri Dec 01 12:56:33 EST 2017 | emeto

It seems that it will work with 5 mil stencil. To be safe use 4 mil if the rest of the design allows it. 10x20mil apertures for both rows. If you have bigger footprint in the corners, make bigger apertures there. For the ground plane, I would use ver

Poor Reflow with Ground Planes for Wave Solder

Electronics Forum | Thu Aug 13 15:46:57 EDT 2020 | ironsmt

I'm having a problem getting sufficient solder reflow on a SMD part. The board design (which can't be changed) is covered in ground planes that cause a lot of uneven heat distribution. I believe heat is wicking away from the culprit part, causing t

SN100C wetting problems

Electronics Forum | Fri Jul 13 12:27:30 EDT 2007 | jseagle

As in more dwell? We see the same problem with through holes connected to power or ground planes. The solder reaches the plane and stops. We are having our boards re-designed to increase the thermal relief and expand the hole size. We are also tr