High-density high-performance flexible cables for digitalapplications

摘要

In this paper we investigate the range of usage for high-densityflexible cables in high-performance applications. We characterize theelectrical performance of a test vehicle containing several flexibletransmission line structures built on a Kapton film. The results oftime-domain measurements with a novel short-pulse propagation techniqueare presented. 15 ps and 35 ps risetime sources are launched on theexperimental structures. This broad-band measurement technique is usedto determine frequency-dependent characteristics up to 25 GHz. It isshown that in order to compete with coaxial cables or opticalinterconnections, an asymmetrical shielded triplate design needs to beused for flexible-film cables. Such a structure offers very lowcrosstalk, controlled impedance, no radiation and relatively inexpensivefabrication. Based on the experimentally developed models, it ispredicted that flexible-film cables can transfer data at 1 Gb/s rates,with lengths of up to 83-165 cm when the line widths are in the range of55-212 μm