Bill, This is called "copper thieving". The concept is that the presence of the small squares will distribute the plating across the area of the pcb. Theiving is generally used when there are areas on a pcb surface that have densely packed plated features mixed with very little plated features. Connectors that have many holes in a small area on a pcb may have theiving squares added around the connector pattern to control the amount of plating in the holes. Chris ********************** Chris Heard Teradyne Work: 603-879-1031 Cell: 508-277-5780 SMS Text Message: 5082775780@xxxxxxxxx Email: christopher.heard@xxxxxxxxxxxx "Bill Mueller" <williamm@xxxxxxx To: <si-list@xxxxxxxxxxxxx> > cc: Sent by: Subject: [SI-LIST] "checkered" copper plane question si-list-bounce@fr eelists.org 05/13/2003 01:36 PM Please respond to williamm Hello all, I've been hitting a couple embedded design shows lately and have been seeing a couple prototype boards that have the top and bottom copper planes 'checkered' That is instead of a large continuous plane, the plane has been cut into a grid of 1-2mm squares. Has anyone else seen this? What are the benifits of this type of layout? Thanks, -Bill BTW: The guys manning the booth had answers ranging from 'I don't know' to 'better aestetics' to 'complex proprietary EMI interfusion grid' :) ------------------------------------------------------------------ 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 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 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