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The rapid development of wearable technology has received another boost from a new development using graphene for printed electronic devices. New research from The University of Manchester has demonstrated flexible battery-like devices printed directly on to textiles using a simple screen-printing technique. The current hurdle with wearable technology is how to power devices without the need for cumbersome battery packs. Devices known as supercapacitors are one way to achieve this. A supercapacitor acts similarly to a battery but allows for rapid charging which can fully charge devices in seconds. Now a solid-state flexible supercapacitor device has been demonstrated by using conductive graphene-oxide ink to print onto cotton fabric. As reported in the journal 2D Materials the printed electrodes exhibited excellent mechanical stability due to the strong interaction between the ink and textile substrate. Further development of graphene-oxide printed supercapacitors could turn the vast potential of wearable technology into the norm. High-performance sportswear that monitors performance, embedded health-monitoring devices, lightweight military gear, new classes of mobile communication devices and even wearable computers are just some of the applications that could become available following further research and development. To power these new wearable devices, the energy storage system must have reasonable mechanical flexibility in addition to high energy and power density, good operational safety, long cycling life and be low cost. Dr Nazmul Karim, Knowledge Exchange Fellow, the National Graphene Institute and co-author of the paper said: "The development of graphene-based flexible textile supercapacitor using a simple and scalable printing technique is a significant step towards realising multifunctional next generation wearable e-textiles." "It will open up possibilities of making an environmental friendly and cost-effective smart e-textile that can store energy and monitor human activity and physiological condition at the same time". Graphene-oxide is a form of graphene which can be produced relatively cheaply in an ink-like solution. This solution can be applied to textiles to create supercapacitors which become part of the fabric itself. Dr Amor Abdelkader, also co-author of the paper said: "Textiles are some of the most flexible substrates, and for the first time, we printed a stable device that can store energy and be as flexible as cotton. "The device is also washable, which makes it practically possible to use it for the future smart clothes. We believe this work will open the door for printing other types of devices on textile using 2D-materials inks." The University of Manchester is currently completing the construction of its second major graphene facility to complement the National Graphene Institute (NGI). Set to be completed 2018, the £60m Graphene Engineering Innovation Centre (GEIC) will be an international research and technology facility. The GEIC will offer the UK the unique opportunity to establish a leading role in graphene and related 2D materials. The GEIC will be primarily industry-led and focus on pilot production and characterisation. Ref.MS614SE-FL28EML-614S/FN

When designing a custom lighting solution, there are many different goals to take into consideration. One of the most essential may be reducing the power supply needs of the system. Doing so can provide further benefits, such as improving reliability and expected shelf life, and reducing space and size constraints. Benefits often come with tradeoffs; traditionally, when you reduce power you may need to reduce brightness at the same time. The good news is that this doesn’t always have to be the case. GLOBAL LIGHTING TECHNOLOGIES have compiled a list of five smart ways that you can reduce power without sacrificing LED brightness. 1. LED efficiencyHow do you do more with less? It's all about efficiency, and choosing more efficient LEDs can make a world of difference. Choosing a more efficient LED may seem like a more expensive option, but keep in mind that it’s not just about the cost of the LED - what you should really be considering is the cost per Lumen of output. A more efficient LED is actually more cost-effective, while simultaneously helping reduce power needs. 2. Lightguide material efficiencyAny light which is absorbed by the lightguide material is light that the actual display is losing. Therefore, switching to a material with a higher transmissivity to improve efficiency and it will aid in the retention of more light. 3. LED driver circuitBy utilising a highly efficient LED driver circuit, you can prevent power loss and improve the end result. This is often overlooked, as many engineers design circuits which use resistors to reduce voltage and match current to the LEDs. You can prevent those power losses from occurring by using custom designed LED driver chips and circuits with improved efficiency. 4. Lightguide extraction efficiencyAnother area where efficiency can be improved is with extraction, and by doing so more light is able to reach the user’s target area. In turn, power can also be reduced. Our innovative extraction technology offers higher efficiency and overall improved extraction, helping to achieve this goal. 5. LightguidesThe job of a lightguide is to take the light from the LED and spread it out uniformly over the surface being illuminated. With the right design and technology, a custom lightguide can actually conserve most of the initial LED efficiency while greatly increasing uniformity of the display, offering the best of both worlds. Ref.KY32-HV9921N3KY32-MIC2287CBD5KY32-LNK456DG

 Toshiba America Electronic Components, Inc. (TAEC) has expanded its U-MOS IX-H Series of low-voltage N-channel power MOSFETs with the addition of new 40V and 45V products. Delivering high-speed performance and industry-leading1 low on-resistance, the new MOSFETs are designed for industrial and consumer applications, including high-efficiency DC-DC converters, high-efficiency AC-DC converters, power supplies, and motor drives. The new MOSFETs utilize Toshiba’s latest generation low-voltage trench structure U-MOS IX-H process to lower the performance index for “RDS(ON) Qsw”2 figure of merit, improving switching applications to a level that surpasses other offerings3. Output loss is improved by the reduction of output charge, which can contribute to higher set efficiency. Additionally, the cell structures used in the new MOSFETs are optimized to suppress spike voltage and ringing during switching, which can contribute to lowering set EMI. Toshiba’s U-MOS IX-H Series is specifically designed for synchronous rectification applications, including the secondary side of isolated switching power supplies. It provides an improved Qoss4 performance, which is one of the main causes of power loss of synchronous rectification. The U-MOS IX-H Series also provides a low Ron•Qoss, the trade-off characteristics between on-resistance and Qoss. Since Ron has a significant impact on Qoss, Toshiba will extend the U-MOS IX-H portfolio to include MOSFETs having ultra-low Ron in order to supplement its U-MOS VIII-H Series of MOSFETs. Features·Low on-resistance·Low output charge·High-speed performance·Low switching noise·Supports 4.5V logic level drive *About TAECThrough proven commitment, lasting relationships and advanced, reliable electronic components, Toshiba enables its customers to create market-leading designs. Toshiba is the heartbeat within product breakthroughs from OEMs, ODMs, CMs, VARs, distributors and fabless chip companies worldwide.  A committed electronic components leader, Toshiba designs and manufactures high-quality flash memory-based storage solutions, solid state drives (SSDs), hard disk drives (HDDs), solid state hybrid drives (SSHDs), discrete devices, custom SoCs/ASICs, imaging products, microcontrollers, wireless components, mobile peripheral devices, and advanced materials that make possible today’s leading smartphones, tablets, cameras, medical devices, automotive electronics, industrial applications, enterprise solutions and more. Ref.KY68-VS75B-24KY68-DS1200D  

Bigger is always better, isn’t it? That’s not necessarily the case when it comes to specifying an AC/DC power supply. One of the most important aspects of designing a power supply into a system is ensuring that it is sized appropriately. Erring on the side of caution by trying to ensure that the supply’s maximum output exceeds that of the load is no longer the right answer in many cases. Customers increasingly need to focus on energy efficiency. The trend is partly driven by the need to cut operating costs and partly by legislation such as the European Union’s EcoDesign Directive.Under the directive, manufacturers of energy related products need to be able to demonstrate they have taken environmental factors into account. The efficiency of the power delivery sub-system is one of the key factors. It will play a large part in determining how energy will be lost through heat. As a result, choosing a high efficiency PSU (Power Supply Unit) is an important consideration in the design process.A 200W PSU operating at full load with an efficiency of 85% will lose 30W in waste heat. Not only is that heat wasted, there may be an additional energy cost in forced air cooling to prevent the rest of the system overheating. A PSU that is 90% efficient will cut the power wastage by 10W.If that PSU is operated below full capacity, it will run at a lower temperature. That allows usage in higher ambient temperatures or with less forced air cooling. However, there can be a trade off between efficiency and headroom. Many PSUs are designed to provide peak efficiency when they are driving a load close to full capacity. But this efficiency can roll off dramatically beneath 70 or 80% of full load. Using a power supply that is oversized for a particular application may result in an undesirable loss in efficiency and excessive heat production.A potential problem for system designers is that the focus on energy efficiency in electronics has led to the adoption of power saving modes. The resulting load demands can vary widely during operation. Responding to this trend, PSU designers working in the data centre space have embraced initiatives such as 80 PLUS.Launched in the mid 2000s at a Market Transformation Symposium organised by the American Council for an Energy-Efficient Economy, the 80 PLUS idea was quickly adopted as the basis for PSU efficiency marking by the US Energy Star programme. Supported worldwide, the idea behind 80 PLUS was to make PSUs deliver high efficiency over a larger proportion of the load curve. Recognising that many data centre system PSUs are operated using 1+1 redundancy and current sharing, the maximum efficiency point was centred on 50% capacity.Ratings range from Bronze to Titanium. At 50% load, Bronze offers an efficiency of 85%. Titanium pushes the peak efficiency to 96%, rolling off towards 94% when operating at 20% load and 91% at full load. Bel and GE provide wide ranges of PSUs that are graded according to the 80 PLUS standards.An alternative way to approach the issue of variable loads is to use the idea of boost power. This concept is gaining popularity in industrial designs where engineers have to deal with highly capacitive and inductive loads such as motors. As these systems shift between modes, there may be short term peak loads that go some way above normal operation. Motor start up also needs careful handling to deal with high current inrush conditions.Built for the DIN-rail format commonly used in industrial systems, the Cliq-II and Cliq-M series of DIN-rail supplies from Delta offer an ‘Advanced Power Boost’ of 120% for three seconds or 150% for five seconds, respectively. Alternatively, if a PSU has been derated to operate at a lower output level so that it does not need forced air cooling, it can be ramped up to peak load for short periods of time without necessarily demanding additional cooling. However, this usage of a PSU does call for attention to the thermal conditions to ensure that the short term peaks in heating are dissipated.To deal with situations such as high current inrush, PSUs such as the Artesyn LCM600 offer constant current modes that limit how much power is delivered to the load during the kinds of demand surges seen during motor startup. As one of a growing number of PSUs that employ digital control, the LCM600’s firmware can be programmed to support a number of different protection strategies so that the integrator can pick the mode best suited to the application.Reference:C300HC650HXBA-01

Train delays due to leaves on the line could be a thing of the past if a prototype developed at the University of Birmingham is adopted by railway networks.Every year, thousands of commuters endure the frustration of Autumn delays caused by the accumulation of leafy slush on train tracks – and these problems usually reach their peak in mid-November, when leaf loss is coupled with high levels of moisture in the air or on the ground.Lee Chapman, Professor of Climate Resilience from the University, was inspired by the Internet of Things, which uses a range of innovative power, communication and sensing technology to aggregate real-time, on the ground, data.Funded by EPSRC and the Rail Safety and Standards Board, he worked with Alta Innovations, the University of Birmingham's technology transfer company, to transform the concept into a reality. His new technology, called AutumnSense, uses low-cost sensors to continuously measure the level of moisture on the railway line at potentially thousands of sites across the network. By linking this data with a leaf-fall forecast, operators can identify where and when the risk is greatest. This allows the precise and efficient use of automated treatment trains, which can clear the lines before the morning rush hour starts. His team are now testing the next element of the solution which is a low-cost method to count the number of leaves remaining on the trees.Professor Chapman's team had previously developed low-cost devices that are fitted to lamp-posts, and transmit data on road surface temperatures, to show precisely where road gritting is needed, and where it isn't. The road technology, called WinterSense, is currently being tested by commercial partners and is expected to be in mass production by the end of this winter.Professor Chapman said, "One of the major issues with road and rail safety is that hazardous conditions are usually highly localised. For remedial actions to be efficient, and demonstrate 'best value' for the taxpayer, resources should be deployed where they are needed, rather than in a blanket fashion."He is marketing AutumnSense and WinterSense through AltaSense, an operating division of Alta Innovations, and hopes to incorporate by Autumn 2017.He said, "Even though leaf loss and damp conditions can largely be predicted - and despite automated treatment trains working round the clock from October to December - a windy, rainy night still causes havoc for commuters. We have run an initial trial of AutumnSense on a stretch of London Underground tracks that are above ground, and are hoping to move quickly towards a fuller network wide trial."Wet leaves pose a very real safety challenge for train operators, potentially doubling the breaking distance and causing signalling issues, or 'disappearing trains' on the rail control systems due to the electrically insulating effect of the leaves which can prevent operation of track circuits. Leaves on the line are only an issue when they are mixed with moisture or dew, creating a slippery, Teflon-like substance. Reference:KY45-D7E-1KY45-BU-27135-000KY45-1005447-1 

Bird’s new Wideband Power Sensor series of USB Thruline power meters feature five models each suited to a particular application. All capable of measuring True Average Power, Peak Power and Duty Cycle, as well as VSWR/Return Loss, Average Burst Power and CCDF, the WPS series will work with any modulation scheme.The vast majority of RF power meters on the market today, in the milliwatt range, are all focussed on measuring power levels of typically -10dBm +/- 30dB. However, Bird Technologies are one of the few manufacturers to offer RF enquirers equipment capable of measuring “real world” transmitter power levels without the need to use directional couplers or high power attenuators.These new USB Power Meters for “real world” RF power measurements cover; 350MHz to 4GHz (150mW to 150W); 350MHz to 4GHz (25mW to 25W); 25MHz to 1GHz (500mW to 500W); 150MHz to 4GHz (100mW to 25W) and 25MHz to 1GHz (100mW to 100W).Insertion loss is less than 0.1dB (typically 0.05dB) with a VSWR of 1.1:1max (typically 1.05:1), plus a directivity specification of typically 30dB. These parameters contribute to an average power accuracy for all models of ±4% of reading, or 0.17dB, over the full power range at +15 to +350C.All Bird Wideband Power Sensors come with ‘Virtual Power Meter’ software to allow connection to a PC. In addition the WPS will interface with the Bird 5000-XT Digital Power meter, or the majority of the Bird SA / SH series of Site Analysers or SignaHawks.Also announced is the new 7020 Power Sensor, a low cost USB Power Meter similar in operation to the 501XB range. The 7020 contains the same ‘True Average Power’ measurement capabilities within the frequency range of 350MHz to 4GHz (0.15W to 150W), and has an identical accuracy of reading at ±4% +0.05W, or 0.17dB. The 7020 Power Sensor is an ideal low cost, but accurate, USB power meter for many applications.Reference:1005919-1PCUC30M72AV