Hi Steve, We have stopped using Tantalum capacitors for some years now. When we used them in the past, we were using 3X voltage derating for Solid Tantalum capacitors, and 2X derating for Low ESR Organic Tantalum capacitors. Regards, Ravinder Ajmani Server PCB Development Hitachi Global Storage Technologies Email: Ravinder.Ajmani@xxxxxxxxxxxxxx "Salkow, Steven" <steven.salkow@xxxxxxxx> Sent by: si-list-bounce@xxxxxxxxxxxxx 01/26/2009 05:40 PM To si-list@xxxxxxxxxxxxx cc EPICenter pwb-cca Email Forum <pwb-cca@xxxxxxxxxxxxx> Subject [SI-LIST] Failed Tantalum capacitors - package hermeticity compromised Content-type: text/plain; charset=us-ascii Content-transfer-encoding: 7BIT Recently we have had some tantalum capacitors rated at 16V fail on turn of in a 12V circuit. While some percentage of low ESR capacitors experience a high surge infant mortality on first turn on unless serrated by 50% or more, these capacitor were sent for additional electrical screening at an independent test house. Just as a precaution we decided to also sample test the lot for package hermeticity by conducting a bubble test. 25 samples were picked at random from the lot of 450 and 100% of these failed bubble test. Has anyone had this problem before? Has any had counterfeit capacitors? Steven Salkow Lockheed IS&S 3130 Zanker Rd, San Jose Ca. 95134 (408) 473-4058 H: (925) 462-1075 steven.salkow@xxxxxxxx salkow@xxxxxxxxxxxx -- HTML Attachment decoded to text by Ecartis -- -- File: header.htm -- Desc: header.htm ---------------------------------------------------------------------------- ---------------------------------------------------------------------------- ---------------------------------------------------------------------------- ---------------------------------------------------------------------------- ------------------------------------------------------------------ To unsubscribe from si-list: si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field or to administer your membership from a web page, go to: //www.freelists.org/webpage/si-list For help: si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field List technical documents are available at: http://www.si-list.net List archives are viewable at: //www.freelists.org/archives/si-list or at our remote archives: http://groups.yahoo.com/group/si-list/messages Old (prior to June 6, 2001) list archives are viewable at: http://www.qsl.net/wb6tpu ------------------------------------------------------------------ To unsubscribe from si-list: si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field or to administer your membership from a web page, go to: //www.freelists.org/webpage/si-list For help: si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field List technical documents are available at: http://www.si-list.net List archives are viewable at: //www.freelists.org/archives/si-list or at our remote archives: http://groups.yahoo.com/group/si-list/messages Old (prior to June 6, 2001) list archives are viewable at: http://www.qsl.net/wb6tpu