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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.
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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.
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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.

Quantum dot white LEDs achieve record efficiency

Researchers created nanomaterial-based white LEDs that exhibit a record high efficiency thanks to quantum dots that are suspended in solution rather than embedded in a solid. [Credit: Sedat Nizamoglu, Koç University]

 

 

 

 

Researchers have demonstrated nanomaterial-based white-light-emitting diodes (LEDs) that exhibit a record luminous efficiency of 105 lumens per watt. Luminous efficiency is a measure of how well a light source uses power to generate light. With further development, the new LEDs could reach efficiencies over 200 lumens per watt, making them a promising energy-efficient lighting source for homes, offices, and televisions.

"Efficient LEDs have strong potential for saving energy and protecting the environment," said research leader Sedat Nizamoglu, Koç University, Turkey. "Replacing conventional lighting sources with LEDs with an efficiency of 200 lumens per watt would decrease the global electricity consumed for lighting by more than half. That reduction is equal to the electricity created by 230 typical 500-megawatt coal plants and would reduce greenhouse gas emissions by 200 million tons."

The researchers describe how they created the high-efficiency white LEDs in Optica, The Optical Society's journal for high-impact research. The new LEDs use commercially available blue LEDs combined with flexible lenses filled with a solution of nano-sized semiconductor particles called quantum dots. Light from the blue LED causes the quantum dots to emit green and red, which combines with the blue emission to create white light.

"Our new LEDs reached a higher efficiency level than other quantum dot-based white LEDs," said Nizamoglu. "The synthesis and fabrication methods for making the quantum dots and the new LEDs are easy, inexpensive, and applicable for mass production."

Advantages of quantum dots
To create white light with today's LEDs, blue and yellow light are combined by adding a yellowish phosphor-based coating to blue LEDs. Because phosphors have a broad emission range, from blue to red, it is difficult to sensitively tune the properties of the generated white light.

Unlike phosphors, quantum dots generate pure colors because they emit only in a narrow portion of the spectrum. This narrow emission makes it possible to create high-quality white light with precise color temperatures and optical properties by combining quantum dots that generate different colors with a blue LED. Quantum dots also bring the advantage of being easy to make, and the color of their emission can be easily changed by increasing the size of the semiconductor particle. Moreover, quantum dots can be advantageously used to generate warm white light sources like incandescent light bulbs or cool white sources like typical fluorescent lamps by changing the concentration of incorporated quantum dots.

Although quantum dots embedded in a film are currently used in LED televisions, this lighting approach is not suitable for widespread use in general lighting applications. Transferring the quantum dots in a liquid allowed the researchers to overcome the problematic drop in efficiency that occurs when nanomaterials are embedded into solid polymers.

Making efficient white LEDs requires quantum dots that efficiently convert blue light to red or green. The researchers carried out more than 300 synthesis reactions to identify the best conditions, such as temperature and time of the reaction, for making quantum dots that emit at different colors while exhibiting optimal efficiency.

"Creating white light requires integrating the appropriate amount of quantum dots, and even if that is accomplished, there are an infinite number of blue, green, and red combinations that can lead to white," said Nizamoglu. "We developed a simulation based on a theoretical approach we recently reported and used it to determine the appropriate amounts and best combinations of quantum dot colors for efficient white-light generation."

To make the new LEDs, the researchers filled the space between a polymer lens and LED chip with a solution of quantum dots that were synthesized by mixing cadmium, selenium, zinc, and sulfur at high temperatures. The researchers used a type of silicone to make the lens because its elasticity allowed them to inject solutions into the lens without any solution leaking out, and the material's transparency enabled the necessary light transmission.

The researchers showed that their liquid-based white LEDs could achieve an efficiency double that of LEDs that incorporate quantum dots in solid films. They also demonstrated their white LEDs by using them to illuminate a 7-in. display.

"Quantum dots hold great promise for efficient lighting applications," said Nizamoglu. "There is still significant room for technology development that would generate more efficient approaches to lighting."

As a next step, the researchers are working to increase the efficiency of the LEDs and want to reach high efficiency levels using environmentally friendly materials that are cadmium- and lead-free. They also plan to study the liquid LEDs under different conditions to ensure they are stable for long-term application.

Source: Optica

Published August 2018

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