Hi Lou, Phil's comments were correct. Solid Tantalum capacitors do not require the dielectric "reformation" that is necessary after aluminum electrolytics have been stored for a while. There is no electrical shelf life of solid tantalum caps. The only real concern is solderability after several years, but that's the case with any component. And since you indicated that the parts in question are already soldered onto boards, then solderability is obviously not an issue. Nancy Reynolds KEMET Electronics Lou Hart <[log in to unmask]>@ipc.org> on 05/09/2000 12:04:02 PM Please respond to "TechNet E-Mail Forum." <[log in to unmask]>; Please respond to Lou Hart <[log in to unmask]> Sent by: TechNet <[log in to unmask]> To: [log in to unmask] cc: Subject: [TN] Shelf life of tantalum capacitors TechNetters, anyone know of a shelf life for tantalum capacitors? We use some on our own designs here, and want to know how long boards can sit on the shelf before these parts should be replaced. Aluminum electrolytics may be a year, according to my understanding. Thanks for any comments. Lou ############################################################## TechNet Mail List provided as a free service by IPC using LISTSERV 1.8c ############################################################## To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body: To subscribe: SUBSCRIBE TECHNET <your full name> To unsubscribe: SIGNOFF TECHNET ############################################################## Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional information. If you need assistance - contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 ############################################################## ############################################################## TechNet Mail List provided as a free service by IPC using LISTSERV 1.8c ############################################################## To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body: To subscribe: SUBSCRIBE TECHNET <your full name> To unsubscribe: SIGNOFF TECHNET ############################################################## Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional information. If you need assistance - contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 ##############################################################