Mike, I've run into trouble by assuming the board house would equalize dielectric thickness in the layer stack. Some do, some don't.
I now add a fab note to "equalize dielectric thickness +/- 10%" to get an approximately known dielectric thickness. Or you can specify the prepreg thickness between critical copper layers, even in a proto. Brian Foothill Services LLC >i have another question. this is iffy, but i'm a heathen >designer anyway. this is just a proto board, and although i'd >like controlled impedance, i don't want to pay for it. SO, >what i am thinking is that if i get an 8-layer board at the >standard 62 mil thickness, that they are going to be just about >forced to give me between 6 to 8 mils between layers, without >me ever having to spec it. does this sound right? > >thank you, miker > * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * 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/[email protected] * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
