PCB Stackup Analysis and Design, Part 5

摘要

The PCB stackup strongly influences the board impedance, signal integrity and EMI performance of the system.rnIn this five part series, numerous concepts related to stackup creation and analysis have been covered. In Part 1, the four- and six-layer stack-ups, plus several features of microstrip and striplines, were discussed. Three types of microstrip lines consist of surface (or exposed) microstrip, coated microstrip (usually with solder mask) and embedded microstrip.rnIn Part 2, it was emphasized that target characteristic impedance carries a significant effect on stackup parameters. However, impedance determinations based on rectangular trace cross section can yield values different from the impedance of the actual fabricated board because of etching during the manufacturing process (which results in traces resembling trapezoidal shape).