[PEDA] Connection to Power Planes
Re: [PEDA] Connection to Power Planes
There is a No-Connect Rule you can apply to those component pads. Goto D(esign)/R(ules)/Manufacturing/Power Plane Connection Style/Add Then goto Filter Kind and specify Pad, and go find the pad you want. Then on rule Attribute, set it to No Connect. Jeff Stout - Original Message - From: yves Dubois [EMAIL PROTECTED] To: Protel EDA Forum [EMAIL PROTECTED] Sent: Thursday, August 01, 2002 3:10 PM Subject: [PEDA] Connection to Power Planes Hi All, I am routing a 4-layer board with only through hole components. I need to connected the supply pins of my IC's to the supply plane but I would like to go through a decoupling cap first. Is there an easy way for have those pins not connected to the plane? Thanks Yves Dubois Senior PCB Designer. Raytron LTD Montreal, Quebec Canada. * Tracking #: 90502D2E8745104AB51B9641E64976EF99B7E2BC * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * To post a message: mailto:[EMAIL PROTECTED] * * To leave this list visit: * http://www.techservinc.com/protelusers/leave.html * * Contact the list manager: * mailto:[EMAIL PROTECTED] * * Forum Guidelines Rules: * http://www.techservinc.com/protelusers/forumrules.html * * Browse or Search previous postings: * http://www.mail-archive.com/proteledaforum@techservinc.com * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
Re: [PEDA] Connection to Power Planes
Yves, I've found that a sure-fire way to avoid netlist conflicts in this situation is to create a second Schematic part for each IC to be decoupled, changing its power pin Name from VCC or VDD to something like U25_PWR. Replace the original Sch component with this part. This will netlist correctly to your decoupling components. Each Sch part so treated will have to have a unique name for its power pin, or they will all be lumped into the same net. Brian At 04:10 PM 8/1/02 -0400, you wrote: Hi All, I am routing a 4-layer board with only through hole components. I need to connected the supply pins of my IC's to the supply plane but I would like to go through a decoupling cap first. Is there an easy way for have those pins not connected to the plane? Thanks Yves Dubois Senior PCB Designer. Raytron LTD Montreal, Quebec Canada. * Tracking #: 90502D2E8745104AB51B9641E64976EF99B7E2BC * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * To post a message: mailto:[EMAIL PROTECTED] * * To leave this list visit: * http://www.techservinc.com/protelusers/leave.html * * Contact the list manager: * mailto:[EMAIL PROTECTED] * * Forum Guidelines Rules: * http://www.techservinc.com/protelusers/forumrules.html * * Browse or Search previous postings: * http://www.mail-archive.com/proteledaforum@techservinc.com * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
Re: [PEDA] Connection to Power Planes
At 04:10 PM 8/1/2002 -0400, yves Dubois wrote: Hi All, I am routing a 4-layer board with only through hole components. I need to connected the supply pins of my IC's to the supply plane but I would like to go through a decoupling cap first. Is there an easy way for have those pins not connected to the plane? Yes, but it's a bad idea. This one comes up from time to time, it may have originated in old TTL 2-layer design practice, and I can recall thinking that this might be a good thing to do. However, if you make the inner planes close to each other, with, say, 5 mils of prepreg between them, the interplane capacitance will be high with minimal inductance. The decoupling caps then provide support at lower frequencies. By connecting the caps to the plane and isolating the power pins from the plane, which is what I think you want to do, you enlarge the power loop. You do not gain anything but trouble. However, you can isolate pads from the plane by setting a Manufacturing/Power Plane Connection Style design rule of no connect with a scope that covers the pads in question. If necessary, you could set a rule for each individual pad, but it should be possible to use a component class scope, i.e., create a class with the components which you want to not be directly connected to the plane, and then use that class for the design rule. * Tracking #: 21CC67D09BC73742A0A6A78B493B98683FFF59B4 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * To post a message: mailto:[EMAIL PROTECTED] * * To leave this list visit: * http://www.techservinc.com/protelusers/leave.html * * Contact the list manager: * mailto:[EMAIL PROTECTED] * * Forum Guidelines Rules: * http://www.techservinc.com/protelusers/forumrules.html * * Browse or Search previous postings: * http://www.mail-archive.com/proteledaforum@techservinc.com * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
