Multi-connection vias for printed circuit boards

As the performance of digital electronic components improves, maintaining the integrity of high-frequency signals through circuit boards becomes increasingly challenging. The dimensions and material parameters of in-plane circuit board features, such as striplines, microstrips and co-planar waveguides are tuned to control signal impedance. Conventional multi-layer vertical interconnects, which connect between board layers, are not impedance matched to the in-plane signal traces. Multi-connection vias, developed in this thesis, provide a method for matching the impedance of vertical and in-plane features by forming co-cylindrical waveguides. Solutions from a high-frequency full-wave solver provide insight into field interactions within multi-connection vias; and results from these simulations and signal integrity experiments indicate impedance "tuneability" by adjusting the multi-connection via dimensions. The results also suggest that features can be impedance-matched independent of via diameter. Multi-connection vias are formed by creating distinct conductor paths within cylindrical plated through-holes. The thesis explores several alternative manufacturing methods for fabricating these features. A specialized broaching machine and carbide-insert broaches were used to manufacture multi-connection vias for signal integrity experiments. Models of the broach tool and cutting force simulations resulted in several iterations of the broach design.

Department dc:contributor.department

Massachusetts Institute of Technology. Dept. of Mechanical Engineering.

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

1999

Author dc:creator

• Kiani, Sepehr

Advisor dc:contributor.advisor

• Alexander H. Slocum.

• Mechanical Engineering.

Statement dc:rights

• M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/1721.1/8665

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/8665