A Paradigm Shift for SMT Electronics: Micro-Coil Springs Interconnection for Ceramic and Plastic Grid Array Packaged Integrated Circuits

Jim Hester and Mark Strickland
NASA Marshall Space Flight Center
Huntsville, AL

Micro-coil springs (MCS) provide flexible electrical interconnections and allow significant movement in the x, y, and z axes to counteract the thermal expansion and dynamic forces between a microcircuit and a printed circuit board. Micro-coil springs are able to withstand harsh thermal and vibration environments significantly better than the current state of the art.

NASA Marshall engineers have developed a novel interconnection structure for the integrated circuit packages used in aerospace avionic designs. Micro-coil springs replace ball or column grid arrays (BGA/CGA), preventing connection breaks due to thermal and vibration stresses. The innovation replaces solder balls and solder columns, preventing connection breaks due to thermal stress, and providing longer life for electronics. The technology provides flexibility in three dimensions between the ceramic package and the printed circuit board — a distinct improvement upon cast or copper-ribbon-wrapped solder column interconnects, which have limited flexibility and are less capable of withstanding shear stress. The technology offers a novel alternative, providing better flexibility in high temperatures and harsh environments.

Applications for the technology include automotive electronics, oilfield electronics, electronics for use in wet or humid environments, and area array integrated circuits for space applications.

NASA Marshall has signed an exclusive license agreement with Topline Corporation for the micro-coil technology. NASA has filed a Patent Protection Treaty, and Topline is filing foreign patent protection in several countries and plans to sell the product worldwide. Topline/Marshall are collaborating on advancing surface mount technology (SMT).

Topline assists thousands of customers to define and refine their SMT and microelectronics assembly processes. The micro-coil technology will substantially increase interconnection flexibility, offering longer life to these electronics.

For more information, visit http://contest.techbriefs.com/electronics_winner 

Honorable Mentions

Wireless Bluetooth Pressure Transducer

Mark McDaniel, Transducers Direct, Cinncinati, OH

The TDWLB series certified Bluetooth pressure (with optional temperature) transducer is used for remotely measuring pressure and/or media temperature, mea sur ing these where power isn’t available, and monitoring multiple sensors at once. The sensor can be read on a smartphone, tablet, or PC. High and low alarm set points alert the user when pressures have surpassed a programmable threshold. Applications include HVAC (residential, commercial, RV, marine), boilers, chillers, industrial, water/wastewater, and industrial and medical gases.

For more information, visit http://contest.techbriefs.com/transducer 

High-Power, Medium-Voltage Compensator

Tomasz Rawinski, Electrotechnical Institute, Gdansk, Poland

This compensator protects sensitive, high-power, medium-voltage industrial installations against dips, sags, and short-duration interruptions in public power networks. The compensator is based on high-voltage supercapacitors that stand up to 1 million charge/discharge cycles. After detecting a voltage sag or interruption, a load is disconnected from the grid power supply. At the same time, a sinusoidal voltage generator is started. The converter generates supplying voltage using electric energy stored in supercapacitors. When the compensator is on stand-by, the supercapacitors are charged.

For more information, visit http://contest.techbriefs.com/compensator 


NASA Tech Briefs Magazine

This article first appeared in the November, 2014 issue of NASA Tech Briefs Magazine.

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