March 06, 2018 Volume 14 Issue 09

Electrical/Electronic News & Products

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Cool Tools: World's fastest digital ultra-high-speed camera

Vision Research has introduced the Phantom v2640, the fastest 4-Megapixel (MPx) camera available. It features a new proprietary 4-Mpx CMOS image sensor (2048 x 1952) that delivers unprecedented image quality at up to 26 Gpx/sec, while reaching 6,600 frames per second (fps) at full 2048 x 1952 resolution, and 11,750 fps at 1920 x 1080. This is an excellent tool for researchers, scientists, and engineers who need to capture clean, high-resolution images at super high speeds. Go to the Videos tab on the product webpage to see it in action.
Click here to learn more.

Alternatives to screws for compact electronics

Aluminum and stainless steel microPEM TackSert pins from Penn-Engineering provide cost-effective alternatives to micro screws for attaching top panels to base panels or chassis in compact electronic assemblies. They will attach top panels of any material to a base or chassis manufactured from common cast metals (such as magnesium and aluminum) or plastics (such as ABS and printed circuit boards). The pins ultimately eliminate many of the costs and issues associated with screws and integrate unique design features, promoting reliable and effective performance.
Click here to learn more.

New series of tall board-to-board stacker connectors

AVX Corporation has released a new series of tall board-to-board stacker connectors. The new 00-9148 Series tall stacker connectors are cost-effective, reliable, and robust; exhibit excellent resistance to shock and vibration; and help reduce tolerance accumulation in a variety of demanding applications across the automotive, consumer, medical, and industrial markets. The single-piece connectors also reduce assembly time and shorten BOM lists, and feature a double-row design with an 8-mm (+/- 0.2-mm) board-stacking height, a 1-mm pitch, and eight positions, each rated for 1A continuous current. Rated for 125 V, 50 cycles, and temperatures spanning -40 C to 125 C.
Click here to learn more.

Development kit for IoT applications

ON Semiconductor is helping engineers address a broader range of high-growth Internet of Things (IoT) applications through the release of a new multi-sensor shield and expansion of software support for its IoT Development Kit (IDK). The IDK gives access to a wide variety of sensing, processing, connectivity, and actuation possibilities through a range of shields/daughter cards that attach to the Arm SoC motherboard. The multi-sensor shield adds a variety of inertial and environmental sensors. These coupled with, for example, the recently announced Bluetooth low energy (BLE) connectivity shield, enable the rapid prototyping of a wide range of ultra-low power smart home, industrial IoT, and wearable solutions.
Click here to learn more.

AC and DC motorized impellers designed for demanding environments

Orion Fans has expanded its AC motorized impeller product offering with 14 new IP55-rated models and has added a new line of 24-V and 48-V DC motorized impellers with 13 models. The AC motorized impellers provide high airflow for a wide range of harsh and demanding applications. The DC motorized impellers deliver a low-power solution with standard control and monitoring features. The new motorized impeller models are available in popular 133-mm, 175-mm, 182-mm, 220-mm, and 225-mm sizes, expanding the existing range from 133 mm to 400 mm. They feature backward curved plastic or all-metal blades, sealed dual ball bearings, and rugged die-cast aluminum frames. All AC motorized impellers ship with the required capacitor. All DC motorized impeller models include a PWM and Tachometer function.
Learn about AC motorized impellers.
Learn about DC motorized impellers.

Smallest capacitive touch LED sensor display

Visual Communi-cations Company (VCC) recently launched the CSM Series surface-mount capacitive touch LED sensor, which boasts the smallest footprint in the industry. These displays are unique because they measure only 15.0 mm x 15.0 mm x 3.2 mm and can be surface mounted or even reverse mounted to save additional space. The compact, high-output LED sensor displays can be used in a wide range of applications, including: medical devices, home automation and mobile communication devices, as well as portable instruments. Available in green, yellow, red, blue, and white, these touch sensor displays provide streamlined manufacturing and enhanced product life cycle over a mechanical on/off switch because there are no mechanical components to wear down or break.
See these touch LED sensors in action.

High-current connector for high-end battery systems

Amphenol Industrial Products Group has enhanced its SurLok Plus high-current connector and cabling system. The quick connect and locking system includes a high-voltage interlock loop (HVIL) safety feature, as well as electromagnetic interference shielding (EMI) for noise immunity. These features are a requirement of high-end battery systems to ensure safety and proper operation. Ideal for use in electric vehicles, materials handling, hybrid electric vehicles, and in energy storage for commercial and residential battery storage systems, SurLok Plus is a reliable alternative to common compression lugs.
Click here to learn more.

Selection tips for rodless electromechanical and electric rod actuators

When you specify a linear actuator, some basic decisions come first. Do you go with electric or fluid-powered? Do you need the push/pull of an electric rod actuator or the load-carrying action of a rodless electromechanical actuator? Aaron Dietrich from Tolomatic may have your answer. Dietrich has compiled some very good tips for selecting these actuator types.
Learn about selecting linear actuators.

LED controller for automotive lighting designs

Texas Instruments (TI) has introduced the first 3-channel high-side linear automotive light-emitting diode (LED) controller without internal MOSFETs, which gives designers greater flexibility for their lighting designs. The TPS92830-Q1's novel architecture enables higher power and better thermal dissipation than conventional LED controllers, and is particularly beneficial for automotive LED lighting applications that require high performance and reliability. The LED controller's flexible on-board features give designers the freedom to select the best MOSFET for their system requirements. With this new approach, designers can optimize their lighting power designs more quickly and efficiently for automotive system requirements and desired dimming features.
Click here to learn more.

Filter fan kits with louvered sliding and hinged guards

Orion Fans has expanded the industry's lowest cost louvered filter fan kit to include sliding (LFGS Series, push/pull) and hinged (LFGH Series, flip-up) guard versions. Made up of a louvered sliding or hinged fan guard, filter, fan, metal guard, and hardware, the heavy-duty louvered filter fan kits simplify installation and reduce maintenance time and costs. They are easy to open, with no tools required to access the filter. Compared to regular grills or guards, the louvered filtered guards provide ingress protection as well as protecting fingers from fan blades. Standard filtering to 8 microns and specialty filters are available. Louvered guards feature UV protection. Filter fan kits are available with 120-, 172-, 180-, 200-, 225-, and 280-mm fans.
Click here to learn more.

Cartridge fuse for cooking appliances, photovoltaic systems

SCHURTER offers a robust, compact, and cost-effective cartridge fuse (part SHT) with increased breaking capacity and voltage ratings. The high breaking capacity up to 3,500 A at a nominal voltage of 250 VAC meets standards for commercial electric cooking appliances according to UL 197, while the 1,500 A at 500 VAC is suited for a broad range of industrial one- and three-phase systems such as photovoltaic systems and frequency converters for industrial automation. The fuse is also rated for DC applications up to 400 V.
Learn more about the SHT fuse.
Learn more about the SHT Pigtail fuse.

Alternatives to screws for compact electronics

Aluminum and stainless steel microPEM TackSert pins from Penn-Engineering provide cost-effective alternatives to micro screws for attaching top panels to base panels or chassis in compact electronic assemblies. They will attach top panels of any material to a base or chassis manufactured from common cast metals (such as magnesium and aluminum) or plastics (such as ABS and printed circuit boards). The pins ultimately eliminate many of the costs and issues associated with screws and integrate unique design features, promoting reliable and effective performance.
Click here to learn more.

Two-way piloting solenoid valve

The Lee Company’s new 2-way Piloting Solenoid Valve draws on the design elements of the company's ultra-compact and field-proven 3-way valve and provides a simplified flow path for applications requiring only two ports. MultiSeal technology radically simplifies port layout, offers significant space savings, reduces machining costs, and provides superior reliability over traditional sealing methods. Available biased either normally open or closed, and with lead wires or integral electrical connector, the single-coil 2-way Piloting Solenoid Valve weighs only 0.14 lb and consumes just 7.8 W at 28 VDC.
Click here to learn more.

Solving water leak inspection challenges on vehicle assembly lines

About 3% of new vehicles leave the factory with leaks large enough to cause mold growth and damage to expensive electronic components. ON Semiconductor and RFMicron have developed the Moisture Intrusion Detection System that automatically inspects vehicles for leaks at the end of the assembly process using battery-free wireless sensors at specific vehicle points to verify if those spots are wet or dry.
Read the full article.

Easy wire connection to PCB without wire soldering

In the fast-growing LED/lighting market, lead wire is a major component used in connecting a board to a lighting module. The conventional method of manually soldering the wire to a board presents limitations that result in a complicated assembly process and an unstable connection. Yokowo’s new one-action Lead Socket Connector, however, eliminates wire soldering and allows users to easily plug the lead wire into the socket. A two-contact lock structure ensures a reliable connection. Applications for the Lead Socket Connector include LED lighting, LCD television backlights, tablets, PCs, and any device where a lead wire must be soldered onto a PCB.
Click here to learn more.

New way to do solar power: Researchers boost efficiency and stability of optical rectennas

Georgia Tech researchers have developed a new higher efficiency rectenna design. Here, the device's ability to convert blue light to electricity is tested. [Credit: Christopher Moore, Georgia Tech]



By John Toon, Georgia Tech

The research team that announced the first optical rectenna in 2015 is now reporting a two-fold efficiency improvement in the devices -- and a switch to air-stable diode materials. The improvements could allow the rectennas, which convert electromagnetic fields at optical frequencies directly to electrical current, to operate low-power devices such as temperature sensors.

Ultimately, the researchers believe their device design, which is a combination of a carbon nanotube antenna and diode rectifier, could compete with conventional photovoltaic technologies for producing electricity from sunlight and other sources. The same technology used in the rectennas could also directly convert thermal energy to electricity.

"This work takes a significant leap forward in both fundamental understanding and practical efficiency for the optical rectenna device," said Baratunde Cola, an associate professor in the George W. Woodruff School of Mechanical Engineering at the Georgia Institute of Technology. "It opens up this technology to many more researchers who can join forces with us to advance the optical rectenna technology to help power a range of applications, including space flight."

The research was reported January 26 in the journal Advanced Electronic Materials. The work has been supported by the U.S. Army Research Office under the Young Investigator Program, and by the National Science Foundation.

Optical rectennas operate by coupling the light's electromagnetic field to an antenna, in this case an array of multiwall carbon nanotubes whose ends have been opened. The electromagnetic field creates an oscillation in the antenna, producing an alternating flow of electrons. When the electron flow reaches a peak at one end of the antenna, the diode closes, trapping the electrons, then re-opens to capture the next oscillation, creating a current flow.

Optical rectenna schematic: This schematic shows the components of the optical rectenna developed at the Georgia Institute of Technology. [Credit: Thomas Bougher, Georgia Tech]



The switching must occur at terahertz frequencies to match the light. The junction between the antenna and diode must provide minimal resistance to electrons flowing through it while open, yet prevent leakage while closed.

"The name of the game is maximizing the number of electrons that get excited in the carbon nanotube, and then having a switch that is fast enough to capture them at their peak," Cola explained. "The faster you switch, the more electrons you can catch on one side of the oscillation."

To provide a low work function (ease of electron flow), the researchers initially used calcium as the metal in their oxide insulator/metal diode junction. But calcium breaks down rapidly in air, meaning the device had to be encapsulated during operation -- and fabricated in a glovebox. That made the optical rectenna both impractical for most applications and difficult to fabricate.

So Cola, NSF Graduate Research Fellow Erik Anderson, and Research Engineer Thomas Bougher replaced the calcium with aluminum and tried a variety of oxide materials on the carbon nanotubes before settling on a bilayer material composed of alumina (Al2O3) and hafnium dioxide (HfO2). The combination coating for the carbon nanotube junction, created through an atomic deposition process, provides the quantum mechanical electron tunneling properties required by engineering the oxide electronic properties instead of the metals, which allows air stable metals with higher work functions than calcium to be used.

Rectennas fabricated with the new combination have remained functional for as long as a year. Other metal oxides could also be used, Cola said.

The researchers also engineered the slope of the hill down which the electrons fall in the tunneling process. That also helped increase the efficiency, and allows the use of a variety of oxide materials. The new design also increased the asymmetry of the diodes, which boosted efficiency.

"By working with the oxide electron affinity, we were able to increase the asymmetry by more than ten-fold, making this diode design more attractive," said Cola. "That's really where we got the efficiency gain in this new version of the device."

Optical rectennas could theoretically compete with photovoltaic materials for converting sunlight into electricity. PV materials operate using a different principle, in which photons knock electrons from the atoms of certain materials. The electrons are collected into electrical current.

In September 2015 in the journal Nature Nanotechnology, Cola and Bougher reported the first optical rectenna -- a device that had been proposed theoretically for more than 40 years, but never demonstrated.

The early version reported in the journal produced power at microvolt levels. The rectenna now produces power in the millivolt range, and conversion efficiency has gone from 10-5 to 10-3 -- still very low, but a significant gain.

"Though there still is room for significant improvement, this puts the voltage in the range where you could see optical rectennas operating low-power sensors," Cola said. "There are a lot of device geometry steps you could take to do something useful with the optical rectenna today in voltage-driven devices that don't require significant current."

Cola believes the rectennas could be useful for powering internet of things devices, especially if they can be used to produce electricity from scavenged thermal energy. For converting heat to electricity, the principle is the same as for light-capturing oscillations in a field with the broadband carbon nanotube antenna.

"People have been excited about thermoelectric generators, but there are many limitations on getting a system that works effectively," he said. "We believe that the rectenna technology will be the best approach for harvesting heat economically."

In future work, the research team hopes to optimize the antenna operation and improve their theoretical understanding of how the rectenna works, allowing further optimization. One day, Cola hopes the devices will help accelerate space travel, producing power for electric thrusters that will boost spacecraft.

"Our end game is to see carbon nanotube optical rectennas working on Mars and in the spacecraft that takes us to Mars," he said.

This work was supported by the Army Research Office under the Young Investigator Program agreement W911NF-13-1-0491 and the National Science Foundation Graduate Research Fellowship program under grant DGE-1650044.

Published March 2018

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