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Flexible Thinking Redux

Welcome to the resurrection of Flexible Thinking, a flex circuit monthly column I wrote more years ago than I care to remember, but perhaps some of those reading this still do. I am going to guess that given the passage of time, many of the earlier readers may have moved to retirement or perhaps into other industries. To those of you who do remember, I extend my greetings and my thanks for checking back in to read my humble musings and observations on what I think we can agree is one of the most interesting and useful of all electronic interconnection technologies. To those of you who are new to the industry or first-time readers... Welcome! It is my hope that in the columns to follow, you will find useful thoughts and ideas about this fascinating and continually evolving branch of electronic interconnections.

Flexible circuits are known by a few different names depending on one’s global location and language: flexible printed circuits, FPCs, flex circuits, flexi circuits, flexibles, bendables and a few others that are application-specific such as flexible heater circuits and controlled impedance cable constructions. While flex circuits are an original and foundational interconnection technology for electrical and electronic products (one of the first patents for electrical interconnections, issued at the turn of the last century, was arguably a flexible circuit), over the years there have been several forays into technological extensions of the basic idea. One such area of high and increasing interest in the last several years has been stretchable circuits, which the European Union has made significant investments in over the last decade in the pursuit of technologies that facilitate the integration of electronics into wearable products for a wide array of prospective applications from medical monitoring, to communications and fashion. As the name implies, this flex circuit variation is produced on stretchable substrates. The basic manufacturing is not all that difficult but designing and manufacturing conductive circuits that match the stretchiness of the substrate has been a significant challenge and has had researchers working diligently to find ways to accomplish the objective. (For those interested, there is a chapter on this subject in the 4th edition of my book Flexible Circuit Technology.)

There has also been growth of interest in a new branch of electronic interconnection using flexible circuit technology that is being called by some “flexible electronics,” which is an integration of components and sensors and to which the term “flex hybrid electronics” has been applied. This is another area of increasing interest, and the U.S. government has sponsored research and development by both corporations (manufacturers of both materials and finished products) along with a number Institutions of higher learning. There is no real bright line between an assembled flexible circuit and a flex hybrid electronic assembly, but it really does not matter if it helps bring into focus the numerous advantages that can be secured by the integration of flexible interconnections and components.

One of the centers for information gathering and investigation into materials and processes is NextFlex, in Silicon Valley. A little over two years old, NextFlex is rapidly getting the word out and facilitating consortium members’ communications and interaction to flesh out the possibilities in a world where electronics are increasingly being integrated into an everexpanding universe of creative applications, from the whimsical to the highly practical.

It should be evident that there will be a lot of subjects that can be covered in the world of flexible circuits and this space will be used to explore as many as possible in the future. It is a shared objective of the entirety of this new publication created in service to the electronics industry.

I see this space as a shared one and your individual comments, questions and suggestions are not just welcomed but actively requested. Please feel free to share with me or the editors any thoughts relative to what you might want to see covered in the coming issues, and I will do my best to address the subject matter in a future column. Again, welcome one and all and I look forward to sharing the path to growth and discovery that lies ahead.  

Joe Fjelstad is founder and CEO of Verdant Electronics and an international authority and innovator in the field of electronic interconnection and packaging technologies, with more than 150 patents issued or pending. To reach Fjelstad, click here. 

This article originally appeared in the April 2018 issue of Flex007 Magazine, click here.