With TSOP packages, we have done this test for lack of anything more scientific. We have found that even after temperature cycling, ICT, and functional testing that we still have problems with leads being loose on the board. Therefore, the only quick and dirty way of checking for bad leads is to use a dental pick on the leads. I hope this helps. ---------- From: [log in to unmask] To: [log in to unmask] Subject: ASSY: Fine Pitch Solder Joint Inspection Method? Date: Monday, January 13, 1997 9:49PM Hello all, I've got a question, how many of you out there check whether or not a fine pitch solder joint is good by dragging the tip of an exacto-knife blade or a steel pick across the foot of the leads? I have seen it done back in the past by a few inspectors maybe 4 or 5 years ago, but not anytime recently...until I heard about it today. Is this still a common practice? I'm pretty sure it's not the smart thing to do, but when you have someone call and tell you that the fine pitch solder joints on the board you built for them are insufficient because the leads come loose when they check them with an exacto-knife...they sure don't want to hear you tell them that they shouldn't be dragging anything across the leads. I'm almost sure it's not one of the cases where sometimes a solder joint will become plastic during wave soldering and separate from the pad, some of you may have seen that before. You know, where the fillet stays attached to the foot of the lead with a nice wetting angle and all that stuff, but it's not attached to the pad...but I haven't actually seen the actual boards that supposedly has the insufficient solder yet, the customer has to bring them to me... Oh, another thing, these boards have all been through and passed ICT, a 24-hour burn-in, and a functional test after burn-in. So it would seem to me that if I have a problem with my solder joints, it would have showed itself for sure in burn-in... But before they get here, I'd thought I'd ask and see if it's a common practice to rake fine pitch leads with a steel object...by the way, we're talking about .020" pitch QFP devices here... (gimme' some ammo guys!) Thanks in advance! __\/__ . / ^ _ \ . |\| (o)(o) |/| #------.OOOo----oo----oOOO.-----# # Steve Gregory # # SMT Process Engineer # # The SMT Centre Incorporated # # [log in to unmask] # #________________Oooo.__________# .oooO ( ) ( ) ) / \ ( (_/ \_) ************************************************************************ *** * TechNet mail list is provided as a service by IPC using SmartList v3.05 * ************************************************************************ *** * To unsubscribe from this list at any time, send a message to: * * [log in to unmask] with <subject: unsubscribe> and no text. * ************************************************************************ *** * If you are having a problem with the IPC TechNet forum please contact * * Dmitriy Sklyar at 847-509-9700 ext. 311 or email at [log in to unmask] * ************************************************************************ *** *************************************************************************** * TechNet mail list is provided as a service by IPC using SmartList v3.05 * *************************************************************************** * To unsubscribe from this list at any time, send a message to: * * [log in to unmask] with <subject: unsubscribe> and no text. * *************************************************************************** * If you are having a problem with the IPC TechNet forum please contact * * Dmitriy Sklyar at 847-509-9700 ext. 311 or email at [log in to unmask] * ***************************************************************************