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Intro to reed switches, magnets, magnetic fields

This brief introductory video on the DigiKey site offers tips for engineers designing with reed switches. Dr. Stephen Day, Ph.D. from Coto Technology gives a solid overview on reed switches -- complete with real-world application examples -- and a detailed explanation of how they react to magnetic fields.
View the video.

Bi-color LEDs to light up your designs

Created with engineers and OEMs in mind, SpectraBright Series SMD RGB and Bi-Color LEDs from Visual Communi-cations Company (VCC) deliver efficiency, design flexibility, and control for devices in a range of industries, including mil-aero, automated guided vehicles, EV charging stations, industrial, telecom, IoT/smart home, and medical. These 50,000-hr bi-color and RGB options save money and space on the HMI, communicating two or three operating modes in a single component.
Learn more.

All about slip rings: How they work and their uses

Rotary Systems has put together a really nice basic primer on slip rings -- electrical collectors that carry a current from a stationary wire into a rotating device. Common uses are for power, proximity switches, strain gauges, video, and Ethernet signal transmission. This introduction also covers how to specify, assembly types, and interface requirements. Rotary Systems also manufactures rotary unions for fluid applications.
Read the overview.

Seifert thermoelectric coolers from AutomationDirect

Automation-Direct has added new high-quality and efficient stainless steel Seifert 340 BTU/H thermoelectric coolers with 120-V and 230-V power options. Thermoelectric coolers from Seifert use the Peltier Effect to create a temperature difference between the internal and ambient heat sinks, making internal air cooler while dissipating heat into the external environment. Fans assist the convective heat transfer from the heat sinks, which are optimized for maximum flow.
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EMI shielding honeycomb air vent panel design

Learn from the engineering experts at Parker how honeycomb air vent panels are used to help cool electronics with airflow while maintaining electromagnetic interference (EMI) shielding. Topics include: design features, cell size and thickness, platings and coatings, and a stacked design called OMNI CELL construction. These vents can be incorporated into enclosures where EMI radiation and susceptibility is a concern or where heat dissipation is necessary. Lots of good info.
Read the Parker blog.

What is 3D-MID? Molded parts with integrated electronics from HARTING

3D-MID (three-dimensional mechatronic integrated devices) technology combines electronic and mechanical functionalities into a single, 3D component. It replaces the traditional printed circuit board and opens up many new opportunities. It takes injection-molded parts and uses laser-direct structuring to etch areas of conductor structures, which are filled with a copper plating process to create very precise electronic circuits. HARTING, the technology's developer, says it's "Like a PCB, but 3D." Tons of possibilities.
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Loss-free conversion of 3D/CAD data

CT CoreTech-nologie has further developed its state-of-the-art CAD converter 3D_Evolution and is now introducing native interfaces for reading Solidedge and writing Nx and Solidworks files. It supports a wide range of formats such as Catia, Nx, Creo, Solidworks, Solidedge, Inventor, Step, and Jt, facilitating smooth interoperability between different systems and collaboration for engineers and designers in development environments with different CAD systems.
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Top 5 reasons for solder joint failure

Solder joint reliability is often a pain point in the design of an electronic system. According to Tyler Ferris at ANSYS, a wide variety of factors affect joint reliability, and any one of them can drastically reduce joint lifetime. Properly identifying and mitigating potential causes during the design and manufacturing process can prevent costly and difficult-to-solve problems later in a product lifecycle.
Read this informative ANSYS blog.

Advanced overtemp detection for EV battery packs

Littelfuse has introduced TTape, a ground-breaking over-temperature detection platform designed to transform the management of Li-ion battery systems. TTape helps vehicle systems monitor and manage premature cell aging effectively while reducing the risks associated with thermal runaway incidents. This solution is ideally suited for a wide range of applications, including automotive EV/HEVs, commercial vehicles, and energy storage systems.
Learn more.

Benchtop ionizer for hands-free static elimination

EXAIR's Varistat Benchtop Ionizer is the latest solution for neutralizing static on charged surfaces in industrial settings. Using ionizing technology, the Varistat provides a hands-free solution that requires no compressed air. Easily mounted on benchtops or machines, it is manually adjustable and perfect for processes needing comprehensive coverage such as part assembly, web cleaning, printing, and more.
Learn more.

LED light bars from AutomationDirect

Automation-Direct adds CCEA TRACK-ALPHA-PRO series LED light bars to expand their offering of industrial LED fixtures. Their rugged industrial-grade anodized aluminum construction makes TRACKALPHA-PRO ideal for use with medium to large-size industrial machine tools and for use in wet environments. These 120 VAC-rated, high-power LED lights provide intense, uniform lighting, with up to a 4,600-lumen output (100 lumens per watt). They come with a standard bracket mount that allows for angle adjustments. Optional TACLIP mounts (sold separately) provide for extra sturdy, vibration-resistant installations.
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World's first metalens fisheye camera

2Pi Optics has begun commercial-ization of the first fisheye camera based on the company's proprietary metalens technology -- a breakthrough for electronics design engineers and product managers striving to miniaturize the tiny digital cameras used in advanced driver-assistance systems (ADAS), AR/VR, UAVs, robotics, and other industrial applications. This camera can operate at different wavelengths -- from visible, to near IR, to longer IR -- and is claimed to "outperform conventional refractive, wide-FOV optics in all areas: size, weight, performance, and cost."
Learn more.

Orbex offers two fiber optic rotary joint solutions

Orbex Group announces its 700 Series of fiber optic rotary joint (FORJ) assemblies, supporting either single or multi-mode operation ideal for high-speed digital transmission over long distances. Wavelengths available are 1,310 or 1,550 nm. Applications include marine cable reels, wind turbines, robotics, and high-def video transmission. Both options feature an outer diameter of 7 mm for installation in tight spaces. Construction includes a stainless steel housing.
Learn more.

Mini tunnel magneto-resistance effect sensors

Littelfuse has released its highly anticipated 54100 and 54140 mini Tunnel Magneto-Resistance (TMR) effect sensors, offering unmatched sensitivity and power efficiency. The key differentiator is their remarkable sensitivity and 100x improvement in power efficiency compared to Hall Effect sensors. They are well suited for applications in position and limit sensing, RPM measurement, brushless DC motor commutation, and more in various markets including appliances, home and building automation, and the industrial sectors.
Learn more.

Panasonic solar and EV components available from Newark

Newark has added Panasonic Industry's solar inverters and EV charging system components to their power portfolio. These best-in-class products help designers meet the growing global demand for sustainable and renewable energy mobility systems. Offerings include film capacitors, power inductors, anti-surge thick film chip resistors, graphite thermal interface materials, power relays, capacitors, and wireless modules.
Learn more.

Graphene electrodes may be key to next-gen solar cells

A new roll-to-roll production method could enable lightweight, flexible solar devices and a new generation of display screens.

By David L. Chandler, MIT

A new way of making large sheets of high-quality, atomically thin graphene could lead to ultra-lightweight, flexible solar cells -- and to new classes of light-emitting devices and other thin-film electronics.

The manufacturing process, which was developed at MIT and should be relatively easy to scale up for industrial production, involves an intermediate "buffer" layer of material that is key to the technique's success. The buffer allows the ultra-thin graphene sheet, less than a nanometer (billionth of a meter) thick, to be easily lifted off from its substrate, allowing for rapid roll-to-roll manufacturing.

The process is detailed in a paper published Jun 4 in Advanced Functional Materials by MIT postdocs Giovanni Azzellino and Mahdi Tavakoli; professors Jing Kong, Tomas Palacios, and Markus Buehler; and five others at MIT.

A new manufacturing process for graphene is based on using an intermediate carrier layer of material after the graphene is laid down through a vapor deposition process. The carrier allows the ultra-thin graphene sheet, less than a nanometer thick, to be easily lifted off from a substrate, allowing for rapid roll-to-roll manufacturing. These figures show this process for making graphene sheets, along with a photo of the proof-of-concept device used (b). [Image courtesy: MIT researchers]

 

 

 

 

Finding a way to make thin, large-area, transparent electrodes that are stable in open air has been a major quest in thin-film electronics in recent years for a variety of applications in optoelectronic devices -- things that either emit light, like computer and smartphone screens, or harvest it, like solar cells. Today's standard for such applications is indium tin oxide (ITO), a material based on rare and expensive chemical elements.

Many research groups have worked on finding a replacement for ITO, focusing on both organic and inorganic candidate materials. Graphene, a form of pure carbon whose atoms are arranged in a flat hexagonal array, has extremely good electrical and mechanical properties, yet it is vanishingly thin, physically flexible, and made from an abundant, inexpensive material. Furthermore, it can be easily grown in the form of large sheets by chemical vapor deposition (CVD) using copper as a seed layer, as Kong's group has demonstrated. However, for device applications, the trickiest part has been finding ways to release the CVD-grown graphene from its native copper substrate.

This release, known as graphene transfer process, tends to result in a web of tears, wrinkles, and defects in the sheets, which disrupts the film continuity and therefore drastically reduces their electrical conductivity. But with the new technology, Azzellino says, "now we are able to reliably manufacture large-area graphene sheets, transfer them onto whatever substrate we want, and the way we transfer them does not affect the electrical and mechanical properties of the pristine graphene."

The key is the buffer layer, made of a polymer material called parylene, that conforms at the atomic level to the graphene sheets on which it is deployed. Like graphene, parylene is produced by CVD, which simplifies the manufacturing process and scalability.

As a demonstration of this technology, the team made proof-of-concept solar cells, adopting a thin-film polymeric solar cell material, along with the newly formed graphene layer for one of the cell's two electrodes, and a parylene layer that also serves as a device substrate. They measured an optical transmittance close to 90 percent for the graphene film under visible light.

The prototyped graphene-based solar cell improves by roughly 36 times the delivered power per weight, compared to ITO-based state-of-the-art devices. It also uses 1/200 the amount of material per unit area for the transparent electrode. There is a further fundamental advantage compared to ITO. "Graphene comes for almost free," Azzellino says.

"Ultra-lightweight graphene-based devices can pave the way to a new generation of applications," he says. "So if you think about portable devices, the power per weight becomes a very important figure of merit. What if we could deploy a transparent solar cell on your tablet that is able to power up the tablet itself?" Though some further development would be needed, such applications should ultimately be feasible with this new method, he says.

The buffer material, parylene, is widely used in the microelectronics industry, usually to encapsulate and protect electronic devices. So the supply chains and equipment for using the material already are widespread, Azzellino says. Of the three existing types of parylene, the team's tests showed that one of them, which contains more chlorine atoms, was by far the most effective for this application.

The atomic proximity of chlorine-rich parylene to the underlying graphene as the layers are sandwiched together provides a further advantage, by offering a kind of "doping" for graphene, finally providing a more reliable and nondestructive approach for conductivity improvement of large-area graphene, unlike many others that have been tested and reported so far.

"The graphene and the parylene films are always face to face," Azzellino says. "So basically, the doping action is always there, and therefore the advantage is permanent."

The research team also included Marek Hempel, Ang-Yu Lu, Francisco Martin-Martinez, Jiayuan Zhao, and Jingjie Yeo, all at MIT. The work was supported by Eni SpA through the MIT Energy Initiative, the U.S. Army Research Office through the Institute for Soldier Nanotechnologies, and the Office of Naval Research.

Published June 2020

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