Hi Dave, Your comments are well taken; I was responding to a question on accelerated reliability testing for non-automotive use. The temperatures you mentioned certainly can occur for automotive electronics--that is why automotive electronics see one of the most severe use environments-only down-hole drilling is consistently worse. For those applications testing in the -55 to +125C range is appropriate, but not much of an acceleration in terms of increased severity. Shorter cyclic dwell times for the test cycles can give you more acceleration, but those cycles are less damaging (less creep) which needs to be accounted for. Also because of the multiple damage mechanisms determining an acceleration transform from which acceleration factors can be determined is generically near impossible. One can of course establish fixed relationships for a given test environment and a given use environment. Werner Engelmaier Engelmaier Associates, Inc. Electronic Packaging, Interconnection and Reliability Consulting 23 Gunther Street Mendham, NJ 07945 USA Phone & Fax: 201-543-2747 E-mail: [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] * ***************************************************************************