Recent release of power modules constructed on FR4 substrate are designed for reflow soldering, but tend not to specify their coplanarity. Given that a device is measurably coplanar before reflow on a large system card, will this coplanarity be maintained through the reflow temperature profile? What's to stop it from curling like a piece of bacon when its coplanarity is actually needed? Previous versions of these parts were either on ceramic substrate, or terminated with through-hole leads. Any advice on this? R Legg [log in to unmask] --------------------------------------------------------------------------------- Technet Mail List provided as a free service by IPC using LISTSERV 1.8d 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 delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search previous postings at: www.ipc.org > On-Line Resources & Databases > E-mail Archives Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 ---------------------------------------------------------------------------------