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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.
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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.
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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.

Scientists debut most efficient optical rectennas -- devices that harvest power from heat

Scientists at the University of Colorado Boulder have tapped into a poltergeist-like property of electrons to design devices that can capture excess heat from their environment -- and turn it into usable electricity.

The researchers have described their new "optical rectennas" in a paper published May 18, 2021, in the journal Nature Communications. These devices, which are too small to see with the naked eye, are roughly 100 times more efficient than similar tools used for energy harvesting. They achieve that feat through a mysterious process called "resonant tunneling," in which electrons pass through solid matter without spending any energy.

"They go in like ghosts," said lead author Amina Belkadi, who recently earned her PhD from the Department of Electrical, Computer and Energy Engineering (ECEE).

This scanning electron microscope image shows the distinct bowtie shape of an optical rectenna. [Credit: University of Colorado Boulder/Moddel lab]

 

 

 

 

Rectennas (short for "rectifying antennas"), she explained, work a bit like car radio antennas. However, instead of picking up radio waves and turning them into tunes, optical rectennas absorb light and heat and convert it into power.

They're also potential game changers in the world of renewable energy. Working rectennas could, theoretically, harvest the heat coming from factory smokestacks or bakery ovens that would otherwise go to waste. Some scientists have even proposed mounting these devices on airships that would fly high above the planet's surface to capture the energy radiating from Earth to outer space.

So far, however, rectennas haven't been able to reach the efficiencies needed to meet those goals.

Until now, perhaps.

In the new study, Belkadi and her colleagues have designed the first-ever rectennas that are capable of generating power.

"We demonstrate for the first time electrons undergoing resonant tunneling in an energy-harvesting optical rectenna," she said. "Until now, it was only a theoretical possibility."

Study coauthor Garret Moddel, professor of ECEE, said that the study is a major advance for this technology.

"This innovation makes a significant step toward making rectennas more practical," he said. "Right now, the efficiency is really low, but it's going to increase."

An unbeatable problem
It's a development that Moddel, who has literally written the book on these devices, has been looking forward to for a long time. Rectennas have been around since 1964 when an engineer named William C. Brown used microwaves to power a small helicopter. They're relatively simple tools, made up of an antenna, which absorbs radiation, and a diode, which converts that energy into DC currents.

"It's like a radio receiver that picks up light in the form of electromagnetic waves," he said.

The problem, however, is that to capture thermal radiation and not just microwaves, rectennas need to be incredibly small -- many times thinner than a human hair. That can cause a range of problems. The smaller an electrical device is, for example, the higher its resistance becomes, which can shrink the power output of a rectenna.

"You need this device to have very low resistance, but it also needs to be really responsive to light," Belkadi said. "Anything you do to make the device better in one way would make the other worse."

For decades, in other words, optical rectennas seemed like a no-win scenario. That is, until Belkadi and her colleagues, who include postdoctoral researcher Ayendra Weerakkody, landed on a solution: Why not sidestep that obstacle entirely?

A ghostly solution
The team's approach relies on a strange property of the quantum realm.

Belkadi explained that in a traditional rectenna, electrons must pass through an insulator in order to generate power. These insulators add a lot of resistance to the devices, reducing the amount of electricity that engineers can get out.

In the latest study, however, the researchers decided to add two insulators to their devices, not just one. That addition had the counterintuitive effect of creating an energetic phenomenon called a quantum "well." If electrons hit this well with just the right energy, they can use it to tunnel through the two insulators -- experiencing no resistance in the process. It's not unlike a ghost drifting through a wall unperturbed. A graduate student in Moddel's research group had previously theorized that such spectral behavior could be possible in optical rectennas, but, until now, no one had been able to prove it.

"If you choose your materials right and get them at the right thickness, then it creates this sort of energy level where electrons see no resistance," Belkadi said. "They just go zooming through."

Ultimately, that means more power. To test this spooky effect, Belkadi and her colleagues arrayed a network of about 250,000 rectennas, which are shaped like tiny bowties, onto a hot plate in the lab. Then they cranked up the heat.

The devices were able to capture less than 1% of the heat produced by the hot plate, but Belkadi thinks that those numbers are only going to go up.

"If we use different materials or change our insulators, then we may be able to make that well deeper," she said. "The deeper the well is, the more electrons can pass all the way through."

Moddel is looking forward to the day when rectennas sit on top of everything from solar panels on the ground to lighter-than-air vehicles in the air: "If you can capture heat radiating into deep space, then you can get power anytime, anywhere."

Source: University of Colorado Boulder

Published August 2021

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