Experimental design and evaluation of dielectric profile of printed circuit boards
- Resource Type
- Conference
- Authors
- Fuh, Kuen-Fwu; Yan, San-Ji; Liu, Annie; Liao, Eric
- Source
- 2016 11th International Microsystems, Packaging, Assembly and Circuits Technology Conference (IMPACT) Microsystems, Packaging, Assembly and Circuits Technology Conference (IMPACT), 2016 11th International. :172-175 Oct, 2016
- Subject
- Components, Circuits, Devices and Systems
Permittivity
Yarn
Filling
Permittivity measurement
Transmission line measurements
Weaving
Printed circuits
- Language
- ISSN
- 2150-5942
An experiment was conducted to evaluate the permittivity profiles of PCB boards in the directions of filling yarn and warp yarn. The permittivity at different positions is extracted using algorithms of the well-known two-line method. The test vehicles consisted of line pairs of different lengths and were designed to covered proper distance range to properly reflect the periodic permittivity profile and make measurement possible. The extracted permittivity profiles indicate that the permittivity does vary periodically on the PCB real estate and fiber-weave effect on differential skew cannot be neglect. Furthermore, the variation of permittivity behaves differently in the filling-yarn direction and warp-yarn direction. The variation in the warp-yarn direction is larger than the variation in the filling-yarn direction and the relative orientation between Dk and Df are inconsistent in both directions.