Mark, Our in-house assembly wants .015" spacing on pad-pad and pad -trace. Mark > -----Original Message----- > From: Mark Holmes [SMTP:[log in to unmask]] > Sent: Thursday, August 03, 2000 11:08 AM > To: [log in to unmask] > Subject: [DC] Pad to Pad Spacing for Surface mount parts. > > Hi all, > > What guidelines do you follow for the placement of surface mount parts? > (by > this I mean the pad to pad spacing) > I have in front of me IPC-SM-782A which seems particularly vague in this > area. It recommends 0.040" side by side > pad to pad spacing (for what appear to 0805 type parts) and 0.025" for end > to end spacing. I regularly go much closer > than this. I would be most interested to hear what sort of clearances > designers out there are really using (for reflow soldering). > > Our placement machine is able to place parts incredibly close, and I have > never experienced and problems with placement accuracy. > I assume that the soldering process has the biggest influence on pad to > pad > clearances. > > Thanks in advance, > > Mark. > > Mark Holmes PCB Designer > Helvar Merca Ltd. > Hawley Mill, Hawley Road, > Dartford Kent. DA2 7SY > Tel: 01322 222211 > Fax: 01322 282286 > mailto:[log in to unmask] > http://www.helvar.com