Characterization of microstrip meanders in PCB interconnects

Meandering traces are often used to increase delay times in printed circuit board (PCB) interconnects. An accurate analysis of meanders in today´s high speed digital circuits needs to take into account a number of different effects, including near field coupling between the turns of the meander and reflections at the line discontinuities. These effects have a significant impact on the delay and waveshape of the propagated signal. In this paper we analyze microstrip meander structures using a finite difference time domain (FDTD) based full wave method and a quasi-static technique. Signal propagation through meanders with different trace separations is examined. Shortcomings of the quasi-static approach are pointed out. Simple design guidelines are given