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 | 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 | Thu Oct 30 22:29:58 EDT 2008 | davef
For most applications, a nice square [or rectangle] pad works just fine. Assemblers ship boat loads of boards with these every day. It's reasonable for tight decoupling capacitor requirement applications to use round or radiused pads for components
Electronics Forum | Tue Jun 07 15:00:10 EDT 2005 | glenda
what about spacing between pads center to center on 0402.
Electronics Forum | Tue Jun 07 16:25:29 EDT 2005 | davef
We use a 0.012 inch gap betweem 0402 pads.
Electronics Forum | Thu May 29 16:37:57 EDT 2008 | aj
10% reduction on 5 thou. Gap between pads is also critical with 0402's.
Electronics Forum | Tue Jun 07 19:24:44 EDT 2005 | russ
We use a .010" - .012" gap with .020" square pads.
Electronics Forum | Thu May 29 17:19:51 EDT 2008 | dyoungquist
On 0402s we use 20x25 mil pads with a 15 mil gap between the pads on the pcb with ENIG finish, 5 mil stencil with a 1:1 aperture (20x25 mil) and SAC305 lead free solder paste. We very rarely see any tombstoning on 0402s using this setup.
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
