Steve, Several years back we saw the same thing with the Littlefuse series PGB ESD suppressors. We'd run them for a long time with no issues, then hit a lotcode of parts where the green coating chipped or lifted off in the process. Those assemlies were also seeing a fairly aggressive wash, which included a saponified batch cleaning. In the PGB series, I think that the round dots were a special composite polymer and part of the ESD protection. The green coating was nothing more than that. What we observed was that when the coating pulled away, it sometimes removed or tore part of that polymer. We replaced any parts with a non-intact coating. Bruce Tostevin Benchmark Electronics Hudson, NH -----Original Message----- From: TechNet [mailto:[log in to unmask]] On Behalf Of Stephen Gregory Sent: Monday, March 06, 2006 10:19 AM To: [log in to unmask] Subject: [TN] A new one for me, ESD Suppressors... Mornin' Everybody! Last Friday, I had a problem with a new part that I've never used before, and maybe somebody else has seen this problem. It's with something called an ESD Suppressor. It's a little 0603 SMT part that looks a lot like a LED...in fact, that's what I thought it was at first. It's made by Littlefuse. My problem is that there's a little green piece of plastic on the top of it that looks like it's held there with a tiny dot of glue, that is either coming off or breaking during wash. I'm washing the boards in a batch cleaner using Kyzen Aquanox 4512P at 140 F. for 20-minutes followed by a ambient temperature rinse cycle, and a 15-minute 100 F. dry cycle. I did read in the datasheet that I'm probably washing at too high a temperature. The datasheet says that they have been tested IAW ASTM-543 for 4-hours at 40 C., with 3 solutions (H2O, detergent solution, and a defluxer). I didn't know that there was this limitation until we observed the little green pieces of plastic coming off. You can see a picture at: http://stevezeva.homestead.com/files/ESD_Suppressor.jpg My question is; what is that little green plastic piece? There's nothing in the datasheet that describes it. Is it something functional to the part? Or is it something there for pick and place? I've got a call into Littlefuse and I'm just waiting for a call back. But I thought I'd ask you all to see if someone else has run across these little guys before. I don't have a clue about them... Have a good Monday! -Steve Gregory- _______________________________________________________ This message may contain information that is privileged and confidential to LaBarge, Inc. It is for use only by the individual or entity named above. If you are not the intended recipient, you may not copy, use or deliver this message to anyone. In such event, you should destroy the message and kindly notify the sender by reply e-mail. --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 1.8e To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search the archives of previous posts at: http://listserv.ipc.org/archives Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815 ----------------------------------------------------- --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 1.8e To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search the archives of previous posts at: http://listserv.ipc.org/archives Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815 -----------------------------------------------------