Analysis of high-speed bus lines in printed circuit boards

Techniques are investigated for improving the operating speed and driving capabilities of bus lines in a bookshelf-type packaging system. In particular, a parallel distributed circuit model with stubs is introduced for analyzing reflection and crosstalk noise simultaneously. Numerical analysis shows that a tradeoff exists between the upper limit of speed and the number of packages, and that the reduction of stub length will improve the tradeoff. Experiments indicate that the reduction of stub length by surface-mount bus drivers on both surfaces of a PCB is highly effective for achieving high operating speeds