Electronics Forum | Thu May 29 14:35:37 EDT 2008 | rdmundo
Gents, We've been using a round 1:1 aperture for a 5 mils thickness on our stencil design on 0402 and recently, IPC guidelines recommend oblong, homeplate or reverse homeplate. I believed the PCB pad for 0402's area within the recommended size/dimen
Electronics Forum | Wed Jul 01 07:51:29 EDT 2009 | wrongway
Hello All We are going to run our frist 0402 parts soon. do I need to go to .005 stencil or will .006 work ? do I need to use a type 4 paste ? pad design does a standard rectangle work or the round pads ? Thanks in advance for any replies.
Electronics Forum | Thu Jul 02 10:52:45 EDT 2009 | dyoungquist
For 0402s we use type 3 paste. We have .006 and .005 stencils. The .006 works okay but .005 seems to give us slightly better results. We use a 1:1 ratio for the aperture to match the pad, round pad not needed. With accurate placement and a correc
Electronics Forum | Thu Apr 12 09:50:51 EDT 2007 | pjc
There have been many designs of apertures for 0402, round, home plate, inverted home plate and various reduction amounts for square or rectangular apertures. What works best for a given application depends on PCB design, solder land finish, stencil t
Electronics Forum | Wed Feb 05 14:20:45 EST 2003 | Stephen
One thing that worked for me was simply rounding off the pads, making square pads into circlesfor the stencil. It worked but did seem a little strange turning squares into circles for 0603's and 0402's and turning cirlces for BGA's into squares, (bu
Electronics Forum | Tue Jun 14 18:37:18 EDT 2005 | GS
On top to above suggestions,Round pad designe (where possible to get) helps to solve tombstoning pbm. Regards GS
Electronics Forum | Thu Mar 08 12:40:54 EST 2001 | Ralph Merk
We are currently using 0402 resistors and capacitors in our production process. Our equipment is as follows: - DEK 265 - Siemens S25/F5 - Vitronics XPM520(5 zones) - 2% silver solder Alpha WS678 The problem is that randomly some 0402 capacitors are
Electronics Forum | Thu Oct 30 15:07:40 EDT 2008 | jemills
Hello I have a new 0402 pad design on a recent board were building in future. On closer look i thought the pad was a thru hole mount , but upon closer inspection the round pads are for 0402 comps. I had a discussion with the engineer and he said
Electronics Forum | Fri Jan 14 11:16:45 EST 2005 | Dan Gosselin
I have heard of people using a round pad or Home plate design to decrease the incidence of tombstoning on 0402's Anyone have any practical experience on this or is everyone just using the IPC 782 recommended land pattern (28mil x 33mil rectangle pad
Electronics Forum | Fri Jan 14 12:59:07 EST 2005 | Dan Mendoza
I have used the rectangle shapes and round shapes with no noticible difference. The idea is to design the pads to accept the same solder volume per component. Components over two size pads will favor the higher solder volume side during reflow.
