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Test equipment advancing to meet rapidly changing market needs

Although the rise of the IoT, 5G, and advanced automotive electronics markets is instigating rapid changes in technology, test equipment is keeping pace, and not just in extensions to bandwidth specifications or signal resolution. Maureen Lipps, Multicomp Pro Private Label Product Segment Leader, Test and Tools, Newark Electronics, runs through important advances in the industry and its tools.
Read the full article.

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.

Engineered ‘sand' may help cool electronic devices

By John Toon, Georgia Tech

Baratunde Cola would like to put sand into your computer. Not beach sand, but silicon dioxide nanoparticles coated with a high dielectric constant polymer to inexpensively provide improved cooling for increasingly power-hungry electronic devices.

The silicon dioxide doesn't do the cooling itself. Instead, the unique surface properties of the coated nanoscale material conduct the heat at potentially higher efficiency than existing heat sink materials. The theoretical physics behind the phenomenon is complicated, involving nanoscale electromagnetic effects created on the surface of the tiny silicon dioxide particles acting together.

A thermal probe tests heat conductance in a sample of silicon dioxide nanoparticles. The material could potentially conduct heat at an efficiency higher than that of conventional materials. [Credit: Rob Felt, Georgia Tech]

 

 

 

 

The bottom line could be a potentially new class of high thermal conductivity materials useful for heat dissipation from power electronics, LEDs and other applications with high heat fluxes.

"We have shown for the first time that you can take a packed nanoparticle bed that would typically act as an insulator, and by causing light to couple strongly into the material by engineering a high dielectric constant medium like water or ethylene glycol at the surfaces, you can turn the nanoparticle bed into a conductor," said Cola, an associate professor in the George W. Woodruff School of Mechanical Engineering at the Georgia Institute of Technology. "Using the collective surface electromagnetic effect of the nanoparticles, the thermal conductivity can increase 20-fold, allowing it to dissipate heat."

The research, which involved both theory and experiment, has been published online in the journal Materials Horizons, and was highlighted in the July 8 issue of the journal Science. The work was supported by the Air Force Research Laboratory and the U.S. Air Force. Co-authors include Professor James Hammonds at Howard University, and graduate students Eric Tervo from Georgia Tech and Olalekan Adewuyi from Howard University.

In the last several years, theoretical papers have predicted the ability of surface phonon polaritons to increase thermal conduction in nanomaterials made from polar materials like silicon dioxide. Polaritons are quantum quasiparticles produced by strong coupling of electromagnetic waves with an electric or magnetic dipole-carrying excitation. In the specific case of surface phonon polaritons, the electromagnetic waves are coupled to a certain frequency and polarization of vibrating atoms in the material known as optical phonons. When materials are reduced to sizes below 100 nanometers, the surface properties of the material dominate over bulk properties, allowing phonons of heat to flow from particle to particle in the closely packed bed with the assistance of the coupled electromagnetic waves.

Although researchers could not previously measure heat flow from surface phonon polaritons due to experimental difficulties, they have observed their wave propagation when light hits the surface of a nanostructure material, suggesting a potential role in heat dissipation. In addition to the first measurement of heat flow, Cola and his collaborators also found that the effect can occur when thermal energy is added to a packed bed of nanoparticles.

"What we are also showing for the first time is that when you have nanoparticles of the right type in a packed bed, that you don't have to shine light on them," he explained. "You can just heat up the nanoparticles and the thermal self-emission activates the effect. You create an electrical field around the nanoparticles from this thermal radiation."

The researchers decided to experiment with those special properties, first using water to coat the nanoparticles and turn the silicon dioxide nanoparticle bed into a conductor. But the water coating was not robust, so the researchers switched to ethylene glycol, a fluid commonly used in vehicle antifreeze. The new combination increased the heat transfer by a factor of 20 to approximately 1 watt per meter-kelvin, which is higher than the value ethylene glycol or silicon dioxide nanoparticles could produce alone, and competitive with expensive polymer composites used for heat dissipation.

"You could basically take an electronic device, pack these ethylene glycol-coated nanoparticles in the air space, and it would be useful as a heat dissipation material that at the same time, won't conduct electricity," said Cola. "The material has the potential to be very inexpensive and easy to work with."

Silicon dioxide was chosen because its crystalline lattice can generate resonant optical phonons -- necessary for the effect -- at approximately room temperature. Other materials could also be used, but the silicon dioxide nanoparticles provide a good compromise of properties and cost.

"The resonance frequency, converted into the thermal radiation temperature for silicon dioxide, is around 50 degrees Celsius," said Cola. "With this material, we can turn on this effect at a temperature range that a microelectronic device is likely to see."

Though the ethylene glycol works well, it will eventually evaporate. For that reason, Cola plans to identify polymeric materials that could be adsorbed to the silicon dioxide nanoparticles to provide a more stable coating with a reasonable product lifetime.

The effect depends on the collective action of the silicon dioxide nanoparticles.

"We are basically showing a macroscopic translation of a nanoscale effect," Cola said. "Even though the nanoparticle bed is a bulk assembly, it is a bulk assembly that has a lot of internal surface area. The internal surface area is the gateway by which it interacts with the electromagnetic field -- the light and the heat."

So far, the effect has been demonstrated in small amounts of silicon dioxide nanoparticles. Another step would be to scale up the study to demonstrate that heat can be transferred longer distances in larger volumes of the material, Cola said.

"The rate at which the thermal energy goes from one side of the particle to the other side of the particle is constant throughout the nanoparticle bed, so it shouldn't matter how thick the nanoparticle bed is," he explained. "When these particles are close enough together, their modes are coupled, which allows the energy to transport."

Further testing would be needed to ensure the long-term efficiency and to confirm that there are no impacts on the reliability of the electronic devices cooled with the technique, Cola said.

Published August 2016

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