Is it the same pads consistently pulling off and are the pads connected to traces? Toby On Mar 27, 2012 2:19 PM, "Leland Woodall" <[log in to unmask]> wrote: > Folks, > > We've ran across a strange incident and I'd like a little advice from the > group. > > We recently underwent a component vendor change, and part of the first > group of boards were misbuilt due to incorrect polarity (the part marking > was misinterpreted by the vision operator). > > Anyway, an attempt to remove the part by our Repair group resulted in > lifted pads on 10 of the first 12 boards. We've analyzed the lead material > beneath the SEM and it returns 98% tin and 2% silicone. The old style > component comes off quite easily (within 3 seconds), and an analysis of its > leads shows to be 100% tin. It's a 6 pin diode with very little mass. > > What's going on here? Does a 2% silicone mix raise the melting point of > solder by 200 degrees C? > > Please help me understand. > > Thanks, > > Leland > > ________________________________ > > “Confidentiality Notice: > This transmission (including any attachments) may contain confidential > information belonging to the sender and is intended only for the use of the > party or entity to which it is addressed. If you are not the intended > recipient, you are hereby notified that any disclosure, copying, > distribution, retention or the taking of action in reliance on the contents > of this transmission is strictly prohibited. If you have received this > transmission in error, please immediately notify the sender and erase all > information and attachments.” > > ______________________________________________________________________ > This email has been scanned by the Symantec Email Security.cloud service. > For more information please contact helpdesk at x2960 or [log in to unmask] > ______________________________________________________________________ > ______________________________________________________________________ This email has been scanned by the Symantec Email Security.cloud service. For more information please contact helpdesk at x2960 or [log in to unmask] ______________________________________________________________________