Just a suggestion, but would it be too much to ask people who did some of the tremendous studies in simulations and analysis scenerios with printed circuit boards to do best case and worst case scenerios with a RANGE of FR-4 values and then to have the Dk of the board for the frequencies of interest actually MEASURED?
I found that ALL simulations presented used the typical Dk = 4.7 value that can vary with great latitude from mfr to mfr (dependent upon mfr-ing techniques) and can vary with frequency. I even took one person aside after their presentation, (a very good one I might add) and discussed this point with them. They hadn't thought of this. We're talking at the Ph.D. level. Now maybe that isn't such a big concern for them, but it is for me. The 4.7 value is at best a fantasy. Also, my understanding is that "Dielectric Constant" is done with DC voltage while the more general "Permittivity" is done with frequency. Am I being to overly something-or-other? Discussion? Ideas? Flames? Regards, Doug --------- This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to [email protected] with the single line: "unsubscribe emc-pstc" (without the quotes). For help, send mail to [email protected], [email protected], or [email protected] (the list administrators).
