February 26, 2019 Volume 15 Issue 08

Electrical/Electronic News & Products

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Smallest rugged AI supercomputer for avionics

Aitech Systems has released the A178-AV, the latest iteration of its smallest rugged GPGPU AI super-computers available with the powerful NVIDIA Jetson AGX Xavier System-on-Module. With its compact size, the A178-AV is the most advanced solution for artificial intelligence (AI), deep learning, and video and signal processing for next-gen avionic platforms.
Learn more.


Touchless angle sensors get CAN SAE J1939 interface

Novotechnik has added the CAN J1939 interface (developed for heavy-duty vehicles) to its RFC4800 Series of touchless angle sensors measuring angular position up to 360°, turn direction, turns, speed, and operational status. It can provide one or two output channels. It has a longer life and robustness than an optical encoder. It can signal if a sensor needs replacing or average a programmable number of values to output to reduce external noise if present. This is wear-free angle measurement made easy.
Learn more.


Radar level sensor monitors liquids and powders

The innovative FR Series non-contact radar level sensor from Keyence has been designed to monitor the level of both liquid and powder in any environment. This sensor features short- and long-range models, as well as chemical and sanitary options to address a wide array of level sensing applications. Works even when obstructions or harsh conditions are present, such as build-up, steam, or turbulence.
Learn more.


Raspberry Pi launches $70 AI Kit

Artificial intelligence (AI) is all the rage, and the makers of Raspberry Pi have created a way for enthusiasts of the single-board computer systems to take part and do a lot of experimenting along the way.
Read the full article.


3D model sharing at Brother Industries cuts rework

When Brother Industries, maker of printers, computers, and computer-related electronics, deployed Lattice Technology's XVL Player as a viewer for sharing 3D models throughout the processes of product design, parts design, mold design, mold production, and QA of molded parts, they reduced rework significantly -- especially from downstream departments. XVL Studio with its Difference Check Option helped address the rework in mold design, for example, by always keeping everyone informed of design changes.
Read this real-world case study.


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.
Learn more (video included on page).


New! Thermoelectric dehumidifiers for enclosures

Seifert Systems has just introduced its line of compact Soliflex® Series thermoelectric dehumidifiers, with or without condensate pump. These IP 56-rated units are designed to dehumidify enclosures and small control panels, can be used indoors or outdoors, and are maintenance free. When used with a hygrostat, Soliflex dehumidifiers will keep enclosure humidity below a defined level and only operate when needed.
Learn more.


More Stego enclosure heater options from AutomationDirect

Automation-Direct has added more Stego enclosure heaters to their Enclosure Thermal Management lineup. These new 120 to 240 VAC/VDC units include small, flat versions that distribute heat evenly within compact enclosures and are available with 8- or 10-W heating capacities. Also added are compact loop heaters that feature a patented loop body design for increased natural convection airflow, reduced thermal stress on the heater, and better heat transfer. Loop heaters are available in 10- to 150-W heating capacities.
Learn more.


Great design: Handle with integrated lighting/signaling

Signaling and indicator lights, switches, and buttons -- elements that hardly any machine can do without. The new JW Winco cabinet U-handle EN 6284 integrates all these functions into a single, compact element. The new U-handle is designed to enhance the operation of systems and machines. It features an integrated button and a large, colored, backlit area on the back of the handle. These elements can be used individually or in combination, providing a versatile tool for system control and process monitoring that can be seen from across the room.
Learn more.


Engineer's Toolbox: What is ground loop feedback?

Improper grounding can create problems in data logging, data acquisition, and measurement and control systems. One of the most common problems is known as ground loop feedback. Experts at CAS DataLoggers run through five ways to eliminate this problem.
Read the full article.


AI development kit for multi-camera products

The QCS6490 Vision-AI Development Kit from Avnet enables engineering teams to rapidly prototype hardware, application software, and AI enablement for multi-camera, high-performance, Edge AI-enabled custom embedded products. The kit facilitates design with the new, energy-efficient MSC SM2S-QCS6490 SMARC compute module based on the Qualcomm QCS6490 processor. Provides support for up to four MIPI CSI cameras and concurrent Mini DisplayPort and MIPI DSI displays.
Learn more.


High-temp cabinet cooler keeps incineration process in business

An EXAIR client company handles waste treatment on a large ship by operating an incinerator. The area where the incinerator is located gets very hot (over 120° F). This causes failures in the electronics package used to control the incineration process. Since compressed air is readily available, EXAIR's Model HT4225 Cabinet Cooler System is being used to keep the panel cool. It saved the customer from having to replace their control units due to the hot conditions in the incinerator room. Thermostat control is also available, conserving air and operating only when needed to minimize air consumption.
Learn about EXAIR's huge selection of Cabinet Coolers.


Compact snap-in capacitors for general-purpose applications

TDK's new EPCOS B43659 series of snap-in aluminum electrolytic capacitors is the next generation of ultra-compact, general-purpose components for voltages of 450 V (DC) featuring an extremely high CV product. It provides the same features and serves the same applications as the previous series but is much more compact. These RoHS-compliant capacitors can be used in a wide range of applications, such as switched-mode power supplies, frequency converters, UPS, medical equipment, and solar inverters.
Get all the specs.


Conductive Brush Ring overcomes current leakage in EV powertrains

SKF's new Conductive Brush Ring paves the way to greater reliability and longer life in high-performance electric vehicle powertrain systems. Using pure carbon fiber bristles, it provides a reliable electrical connection between an EV eAxle rotor shaft and its housing. When used in combination with SKF Hybrid ceramic ball bearings, it helps to alleviate parasitic current effects that can lead to premature failure in bearings and other components. Available in different configurations for wet (oil-lubricated) motor designs -- and soon for dry (sealed) applications.
Learn more.


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.


Firefly-inspired surfaces improve efficiency of LED lightbulbs

A new type of light-emitting diode lightbulb could one day light homes and reduce power bills, according to Penn State researchers who suggest that LEDs made with firefly-mimicking structures could improve efficiency.

"LED lightbulbs play a key role in clean energy," said Stuart (Shizhuo) Yin, professor of electrical engineering. "Overall commercial LED efficiency is currently only about 50 percent. One of the major concerns is how to improve the so-called light extraction efficiency of the LEDs. Our research focuses on how to get light out of the LED."

Fireflies and LEDs face similar challenges in releasing the light that they produce, because the light can reflect backwards and is lost. One solution for LEDs is to texture the surface with microstructures -- microscopic projections -- that allow more light to escape. In most LEDs these projections are symmetrical, with identical slopes on each side.

Fireflies' lanterns also have these microstructures, but the researchers noticed that the microstructures on firefly lanterns were asymmetric -- the sides slanted at different angles, giving a lopsided appearance.

Saphire surface with asymmetrical pyramids to produce more light in LEDs. [Credit: Yin Lab/Penn State]

 

 

"Later I noticed not only do fireflies have these asymmetric microstructures on their lanterns, but a kind of glowing cockroach was also reported to have similar structures on their glowing spots," said Chang-Jiang Chen, doctoral student in electrical engineering and lead author in the study. "This is where I tried to go a little deeper into the study of light extraction efficiency using asymmetric structures."

Using asymmetrical pyramids to create microstructured surfaces, the team found that they could improve light extraction efficiency to around 90 percent. The findings were recently published online in Optik and will appear in the April print edition.

Typical sapphire surface with symmetric pyramids. [Credit: Yin Lab/Penn State]

 

 

According to Yin, asymmetrical microstructures increase light extraction in two ways. First, the greater surface area of the asymmetric pyramids allows greater interaction of light with the surface, so that less light is trapped. Second, when light hits the two different slopes of the asymmetric pyramids there is a greater randomization effect of the reflections and light is given a second chance to escape.

After the researchers used computer-based simulations to show that the asymmetric surface could theoretically improve light extraction, they next demonstrated this experimentally. Using nanoscale 3D printing, the team created symmetric and asymmetric surfaces and measured the amount of light emitted. As expected, the asymmetric surface allowed more light to be released.

The LED-based lighting market is growing rapidly as the demand for clean energy increases, and it is estimated to reach $85 billion by 2024.

"Ten years ago, you go to Walmart or Lowes, LEDs are only a small portion (of their lighting stock)," said Yin. "Now, when people buy lightbulbs, most people buy LEDs."

LEDs are more environmentally friendly than traditional incandescent or fluorescent lightbulbs because they are longer lasting and more energy efficient.

Two processes contribute to the overall efficiency of LEDs. The first is the production of light -- the quantum efficiency -- which is measured by how many electrons are converted to light when energy passes through the LED material. This part has already been optimized in commercial LEDs. The second process is getting the light out of the LED -- called the light extraction efficiency.

"The remaining things we can improve in quantum efficiency are limited," said Yin. "But there is a lot of space to further improve the light extraction efficiency."

In commercial LEDs, the textured surfaces are made on sapphire wafers. First, UV light is used to create a masked pattern on the sapphire surface that provides protection against chemicals. Then when chemicals are applied, they dissolve the sapphire around the pattern, creating the pyramid array.

"You can think about it this way, if I protect a circular area and at the same time attack the entire substrate, I should get a volcano-like structure," explained Chen.

In conventional LEDs, the production process usually produces symmetrical pyramids because of the orientation of the sapphire crystals. According to Chen, the team discovered that if they cut the block of sapphire at a tilted angle, the same process would create the lopsided pyramids. The researchers altered just one part of the production process, suggesting their approach could easily be applied to commercial manufacture of LEDs.

The researchers have filed for a patent on this research.

"Once we obtain the patent, we are considering collaborating with manufacturers in the field to commercialize this technology," said Yin. Other researchers who worked on the project were Jimmy Yao, Wenbin Zhu, Ju-Hung Chao, Annan Shang, and Yun-Goo Lee, doctoral students in electrical engineering.

Source: Penn State

Published February 2019

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