Connect the Dots: Best Practices for Prototyping
Designer’s Notebook: DFM Principles for Flexible Circuits
Elementary, Mr. Watson: Flex Designs—The Future and BeyondEffective Characteristic Impedance
March 4, 2015 | Kirk Fabbri, KSPT Engineering ConsultingEstimated reading time: Less than a minute
In a typical interconnect, there lie multiple places where capacitance plays a factor in the signal integrity. This includes the driver and receiver output/input capacitance, as well as the packages, vias, and the transmission lines. Failing to optimize these parameters can often lead to unwanted reflections, excessive radiated and or conducted emissions, and sometimes failure of components and systems.
Reflections can occur anytime there is an impedance mismatch on the line. Sources of mismatches are plentiful and include trace width changes, vias, stubs, reference plane changes, and even the so-called fiber weave effect. In this case, a trace can encounter a different dielectric constant depending on whether it is routed over glass or the epoxy resin in the dielectric material.
In this investigation, it is the capacitive contribution of the different components that are of interest, and how they affect the characteristic impedance the driver sees.
To read the rest of this article, click here.
Share on:
Suggested Items
Rigid-flex Design Guidelines
09/27/2023 | Cherie Litson, CID+, Litson1 ConsultingRigid-flex circuits are unique structures; part rigid board and part flex, they’re increasingly working their way into many of the electronic devices we use every day. There have been many advances in rigid-flex lately as more companies find themselves exploring this technology. So, before I started writing this article about rigid-flex design, I double-checked a few things. Fortunately, there is plenty of rigid-flex information available on a variety of great websites that we all know and trust.
Cutting-edge Inspection Challenges
09/26/2023 | Brent Fischthal, Koh Young AmericaKoh Young’s Brent Fischthal explains how UHDI and advanced packaging are challenging inspection systems. He says the shift toward larger components and advanced packaging brings a host of challenges that impact the industry. These challenges include complexity, density, package diversity, and inspection methodologies, all of which necessitate a more innovative approach.
Seika Machinery Announces Special Sale on McDry DXU-580UF Feeder Storage Cabinet
09/15/2023 | Seika Machinery, Inc.Seika Machinery, Inc., a leading provider of advanced machinery, materials and engineering services, is pleased to announce a special sale on the McDry DXU-580UF Feeder Storage Cabinet.
IDTechEx Asks Where Flexible Hybrid Electronics Add the Most Value
09/11/2023 | PRNewswireCan digital and/or high throughput manufacturing be applied to circuit boards? Can stretchable electronics be produced without sacrificing processing capabilities?
Model Citizens: Modelithics
08/28/2023 | Andy Shaughnessy, Design007 MagazineWe recently asked Chris DeMartino, an applications engineer at Modelithics, to discuss the company’s focus on providing simulation models, primarily for the RF and microwave segments. In this interview, Chris explains the Modelithics business “model” and why the need for good models continues to grow at a rapid pace.