Can you say 'Slot Antenna'... <grin> I think Lee Hill's presentation at PCB West on EMI/EMC demonstrated so well the danger of split planes and crossing the split with high speed signals or RF and the resulting harmonic EMI levels that spilled out all over the radio frequency spectrum.. Seriously, placement is the key.... and never cross the split or better yet have no split at all. Bill Brooks -----Original Message----- From: Jack C. Olson [mailto:[log in to unmask]] Sent: Monday, July 14, 2003 1:26 PM To: [log in to unmask] Subject: Re: [DC] Reference Planes for Impedance Controlled Signals 8MHz Here's more info. We have a PowerPC processor BGA that has many +5V and +2.6V pins. Instead of trying to do a split plane, and having the impedance controlled stuff possibly traveling over a split, I thought it was better to have both a solid +5v plane and solid +2.6v planes on different layers. But as soon as you do that, you have some signals closer to one plane that the other, and the question is will there be signal integrity issues by using the +5v plane as a reference. On the other hand, how do you guys create complicated split planes and keep signals from crossing the split? (Veribest/Mentor Expedition/Mentor BoardStationRE router) thanks, Jack Karl Bates <[log in to unmask] > Sent by: DesignerCouncil To: [log in to unmask] <DesignerCouncil@listse cc: rv.ipc.org> 07/14/2003 02:10 PM Subject: Re: [DC] Reference Planes for Impedance Controlled Signals Please respond to "(Designers Council Forum)"; Please respond to Karl Bates Caterpillar: Confidential Green Retain Until: 08/13/2003 Retention Category: G90 - General Matters/Administration And...What frequency is the circuit operating at ? Khz or Mhz or Ghz ? ---------------------------------------------------------------------------- ----- DesignerCouncil 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 DesignerCouncil. To set a vacation stop for delivery of DesignerCouncil send: SET DesignerCouncil NOMAIL 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 ---------------------------------------------------------------------------- ----- --------------------------------------------------------------------------------- DesignerCouncil 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 DesignerCouncil. To set a vacation stop for delivery of DesignerCouncil send: SET DesignerCouncil NOMAIL 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 ---------------------------------------------------------------------------------