Could anyone give me some insight as to why heatsinks would be isolated from ground planes? My first thought would be to minimize emission or absorption of noise, but I've never had a problem with this...that I know of, anyway! Also, has anyone had any experience with using a copper layer to transfer heat from a heatsink to...(for instance an aluminum case). The heatsink is applied directly to the copper layer and a few inches away the copper layer is attached to an aluminum case via a bracket. (the aluminum case is sealed closed). Any insight would be greatly appreciated!!! Thanks, Joe Reichert ############################################################## IPC Designers Council 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 DESIGNERCOUNCIL <your full name> To unsubscribe: SIGNOFF DESIGNERCOUNCIL ############################################################## Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional information. For the technical support contact Dmitriy Sklyar at [log in to unmask] or 847-509-9700 ext.311 ##############################################################