Zigbee RF control
Clock/Timing ConNectors Interface
Energy Management Motors RF Diodes
MCUs MEMS Touch Screen Display
RF power transistors
Image SensorsOptical Sensors Optocoupler
Power/Battery Management ICs
RF small signal transistors
Home Automation & Smart Metering LIVEWIRE | MARKETWATCH | EMBEDDED CORNER WORLDVIEW | ROADTEST | TECHTRENDS | GET TECH
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Home Automation and Smart Metering This edition of Technology First is focused on Home Automation and Smart Metering, a very exciting area which has recently seen many changes in accessibility, and even philosophy. New technologies have driven down costs, added functionality and made implementation much easier. There are two aspects of Home Automation and Smart Metering; comfort and power savings. Advances in touch screen technology, high performance processing and networking, wireless communications and sensor equipment have given us the ability to control our environment better than ever before. We can stream movies or music in any room; we can control temperature, set alarms and operate equipment anywhere in the home, and in some cases, perform these actions remotely through our phones and PDAs. Power Saving Rising fuel costs and larger populations are putting more strain on our power grids, which, in turn, leads to higher utility bills. Smart meters can monitor our energy usage and report to both ourselves and utility companies. The metering allows us to see how much energy we are using and how much it will cost. It also allows utilities to tailor charges to peak and off-peak periods, relieving the strain on the power grid. The visibility and transparency that Smart Metering brings can be combined with the control of Home Automation to offer unprecedented management over our environment. The two can be combined to switch on and off heating and air conditioning at certain times, or when we are not in the room, saving energy, and of course, money. In this issue we take a look at these enabling technologies through a series of technical articles written by leading suppliers in the field, and our own in-house technical experts. We will also include two fantastic giveaways on RoadTest and the latest news and views in MarketWatch and LiveWire. I always love to hear your feedback on the magazine. If you would like to contribute any ideas or suggestions, please get in touch with me at email@example.com
David Shen Global Head, Technical Marketing, Premier Farnell
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CONTENTS 7 LiveWire
The latest news and trends for Home Automation
Jack Murray takes an in-depth look at this monthâ€™s theme
Gary Nevison gives us a run through of what to expect in the next year
Your chance to test the latest products from NXP and Microchip
Get the latest updates on the EAGLE software
16 Home Automation and Smart Metering,
Technology can make our lives easier, but at the same time we must conserve energy. Our selection of articles covers both these interesting and relevant subjects
36 Embedded Corner We take a look at Microchipâ€™c Smart Metering offerings
What are the main problems for small businesses and how can these be overcome?
View a selection of our market leading Home Automation and Smart Metering products
42 Get Tech
All your technology questions answered
Editorial Staff | Editorial Director Jamie Furness | Editor-in-Chief Alistair Winning | Editor Janice Fleisher | Technical Editor Randall Restle | Creative Director David Macaluso | Art Director Gamilah Smith | Publishing Manager Judy Medhurst | Program Manager Melissa Tucker |
Global news 212 Million “Smart” Electric Meters by 2014 New York, US According to a new study from ABI Research, the number of smart electric meters deployed worldwide will rise from a 2009 level of 76 million to reach about 212 million by 2014. Regulation of smart grid could slow market Glen Allen, Virginia NanoMarkets’ new report on the future development of the Smart Grids market claims there will likely be a slowdown in the future due to government regulation, standards setting and interoperability issues. Collaboration on Powerline Communication/Wireless Gateway Paris, France Watteco SAS and Coronis are collaborating to design a compact, low-cost home automation gateway. The gateway merges both Watteco’s Watt Pulse Communications (WPC) and Wavenis wireless technologies. Ultra-low-power wireless MCU Family Nuremberg, Germany Silicon Labs’ new ultra-low-power Si10xx wireless MCU family addresses the power and RF requirements of battery-operated home automation systems, smart meters, in-home utility monitors and security systems. Siemens €250 million Indian renewable energy investment Munich, Germany Siemens intends to invest more than €250 million over the next three years in India. A major part of this will be invested in renewable energy and value-priced products business. Worldwide semiconductor revenue to grow 20% Stamford, US Worldwide semiconductor revenue in 2010 is forecast to reach US $276B, a 19.9% increase from 2009 revenue of US$231B, according to the latest outlook by Gartner.
New York Glen Allen Paris Nuremberg MunicH Stamford London SunnyVale DallAS Chicago Tel Aviv
Automation to find increased application in power industry London, UK New analysis from Frost & Sullivan finds that emerging economies mostly invest in greenfield power projects, the developed economies invest in retrofits and smart grids. Case study details benefits of APIX high-speed serial link interface Sunnyvale, US Fujitsu Microelectronics issued a new case study detailing its collaboration with Inova Semiconductors and tier-one suppliers to develop an advanced, cost-efficient display technology solution for in-vehicle applications. Smart Energy Gateway Nuremberg, Germany Digi International’s ConnectPort X2 for Smart Energy gateway is a ZigBee Smart Energy certified gateway that easily connects certified ZigBee Smart Energy devices from a Home Area Network (HAN) to an energy service provider via broadband. Low-power, low-voltage RF front end Dallas, US Texas Instruments’ CC1190 RF Front End for low-power and low-voltage wireless applications at 850 - 950MHz integrates a power amplifier (PA), a low-noise amplifier (LNA), switches, and RF matching.
Exelon helps fund Illinois clean coal demonstration plant Chicago, US Exelon will join the FutureGen Alliance, a non-profit organization developing a 275MW integrated gasification combined-cycle facility. The plant will be designed to capture carbon emitted and store it underground. IAR development tools selected for smart metering Nuremberg, Germany IAR Systems entered into a 3 year software license agreement with Landis+Gyr, a specialist in supplying energy management solutions. The agreement establishes IAR as the preferred vendor of development tools. Simplified development of real-time Ethernet networks Nuremberg, Germany Xilinx’s Targeted Design Platform is optimized for industrial automation system design with Spartan-6 FPGAs. The platform accelerates development of real-time Ethernet networks enabling high-speed connectivity and reliable communications. RADCOM to supplies UMTS monitoring expansion to Israel Tel Aviv, Israel RADCOM announced that Cellcom Israel has decided to expand deployment of RADCOM’s RANalysis to monitor and optimize its entire UMTS radio network. n
It’s the means to an innovation. Power Architecture® SoC Platforms They can navigate highways. Connect millions of mobile calls. Stream highdeﬁnition videos with uninterrupted clarity. And that’s just to start. They’re our Power Architecture system-on-chip (SoC) platforms—and they’re an innovator’s dream. Freescale offers the widest performance range of compatible Power Architecture cores in the industry—plus the ability to scale to multicore conﬁgurations without sacriﬁcing your power budget. Add to that our ﬂexible IP modules that efﬁciently accelerate applications and you have outstanding performance with the ultimate in design freedom. There’s no telling where you can take it.
Introducing the MPC8308 processor, ideal for applications where size, power and cost are critical. freescale.com/PowerQUICC Freescale and the Freescale logo are trademarks or registered trademarks of Freescale Semiconductor, Inc. in the U.S. and other countries. All other product or service names are the property of their respective owners. The Power Architecture and Power.org word marks and the Power and Power.org logos and related marks are trademarks and service marks licensed by Power.org. © Freescale Semiconductor, Inc. 2010.
Smart metering registers
high growth potential By Jack Murray, Market Research Manager, Newark
Energy efficiency driven by technology has become a hot topic of conversation in board rooms, legislatures and homes in every part of the world. Smart metering stands out as being one of the most promising, truly transformative new technologies. The populist groundswell on the consumer side is in harmony with the goals of utility providers, as both stand to benefit mightily from a more transparent and directly manageable smart power grid. Pike Research, a leading provider of clean technology market intelligence, estimates that more than 250 million smart meters will be installed worldwide by 2015, up from only 46 million in 2008. The opportunity for meter and communication suppliers is expected to reach almost $20 billion between 2010 and 2015. “Smart meters are the vanguard of Smart Grid deployments,” says Clint Wheelock, Managing Director at Pike Research. “Current AMI (advanced metering infrastructure) rollouts are breaking the traditional 15-20 year meter replacement cycle, and represent an unprecedented effort to add intelligence and communications to electrical metering.”
“AMI” is a much more accurate way of describing the movement to smart metering, since the meter itself is only a small portion of the enabling infrastructure. AMI promises a pervasive network infrastructure that goes way beyond merely transmitting usage data back to providers for monthly billing. The next step in the foreseeable future is empowering consumers to directly manage hourly consumption based on peak rate fluctuations. Imagine a web dashboard accessible from a personal computer that charts usage rates and costs by appliance, allowing one to schedule a dishwasher in the middle of the night or dynamically control temperature settings, based on peak rate triggers transmitted back to the household by the utility. Currently most smart meters are connected to a utility’s enterprise IT system through a NAN (Neighborhood Area Network). Usage data is transmitted to the local NAN by way of an RF network or power line transmission, which in turn transmits
the data to a regional hub. In North America, transmissions are handled primarily by RF mesh networks, while in Europe the more dominant early transmission channel is power lines. The most advanced smart meters already include an interface to consumer appliances through a HAN (home area network) with direct linkage to thermostats and major appliances. Not surprisingly, interoperability standards between technology providers are still being worked out, along with appropriate security measures to prevent hackers from compromising systems. Leading semiconductor manufacturers like Texas Instruments and Analog Devices have already developed entire portfolios of products aimed at capitalizing on AMI deployment. One can find a comprehensive array of SOC’s (system on a chip), processors, power management chips and RFID devices that already support the nascent AMI market in 2010. In fact, Texas Instruments has created its own dedicated web portal showcasing its smart metering solutions and related applications. (http:// www.ti.com/corp/docs/landing/ smartmetering/index.html). Market research firm AMI estimates meter shipments in North America were up about 25% for the first half of 2009, while the European market was down about 33% and is expected to experience a temporary lag until around 2011, when large-scale plans begin rolling out. In all regions, the confluence of technology standards and regulations will force vendor communities and governments to work together quickly, but the “smart money” seems to favor the integrated solutions providers over the long term. n
Smart meter shipments by region, world markets: 2008-2015 Source: Pike Research
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Think Embedded? Think FPGAs?
By Gary Nevison, Legislation & Environmental Affairs, Premier Farnell
The last twelve months have clearly witnessed the most significant period of change since RoHS in 2006, with real momentum building and the industry struggling to keep pace with the numerous environmental proposals.
Design engineers have had a lot to consider, with proposals that would lead to many more products falling within scope, potentially more substance restrictions and even a new geography with the first draft, some two years late, of the China RoHS “Catalog”.
bring into scope all electrical products used in buildings and transport, all “fixed installations” and electrical parts in aircraft, trains, ships and commercial vehicles. Equipment covered by the new Category 11 would enter into force in 2014.
of use and this costly exercise must be completed within a specified period of time, otherwise the substance cannot be used. Thereafter, any downstream user can only procure the product from the source of the authorization request, assuming it has been granted.
2009 saw proposals to amend the scope of the RoHS Directive. Further recommendations from the European Commission (EC) in September were quickly followed by the first draft of a recast in November.
The list of restricted substances could increase under the proposals and include PVC, chlorinated plasticizers, organohalogens, flame retardants and three phthalates.
In October 2009 the Chinese Government published the first draft catalog of Electronic Information Products that will be subject to China RoHS restrictions. While the catalog will be updated periodically, the initial scope is limited to telephones and all types of printers that attach to a computer. Substance restrictions and maximum concentration limits are generally the same as with RoHS in the European Union. Ten of the EU exemptions are used for telephones and 12 for printers.
Legislation – a year of change
The political process will move forward and there will probably be a further recast towards the end of 2010 or early next year. providing the European Commission, Council of Ministers and European Parliament can agree on several key issues. The final draft will then be passed to governments for transposition. Among the possible changes to impact design engineers would be a new Category 11, where the scope would simply be “other electrical and electronic equipment not covered in any of the Categories 1 to 10”.
The second batch of 14 REACH substances of very high concern was announced in December 2009 by the European Chemicals Agency (ECHA). This takes the total to 29 with a further batch expected later in 2010. ECHA sources think that as many as 600 to 700 SVHCs could be added to the Candidate List over time. REACH, unlike RoHS, is not simply a case of providing a certificate of compliance but drives the flow of safety information down through the entire supply chain.
It is also possible, if agreement is reached, that the current exclusion of large-scale stationary industrial tools would be deleted; therefore, all EEE, including manufacturing production line equipment, would fall within scope.
This includes automatically providing a Safety Data Sheet (SDS) both at the point of first order, as well as when the SDS is revised. Gathering the SVHC data has proved a challenge with a generally slow response from many manufacturers at the top of the supply chain.
“Equipment that is part of another type of equipment that does not fall in scope” is proposed to change to “part of stationary installations or transport equipment that is not EEE”. This would
We witnessed this with the RoHS Directive during 2005 and 2006, but the response to requests for REACH data has been worse. Seven substances have been approved for authorization
Companies exporting products into China for sale within the country will be required to test their products and be certified compliant by an approved Chinese test house. In the future this may create a bottleneck, as the obligations will enter into force just ten months after the legislation is adopted by the Chinese Government. When the catalog is revised, it is likely that the consumer products theme will continue. So, what will the next 12 months bring? Definitely more substance restrictions, more products falling within scope of the regulations, more revised exemptions, more data requests up and down the supply chain and probably more frustration. n
Sign up to test the latest devices 12
Welcome once again to the RoadTest section of the journal. In this section, we give you the chance to review the latest development kits from our suppliers. There is a slight change to the application process in this issue, you will need to apply through the RoadTest group on element14 to test the featured development kits. The group can be found at www.element-14.com/community/groups/ roadtest. To apply, register or log in to the element14 site, go to the event link for the kit you wish to test and choose the attend option on the right hand side of the page. The element14 group provides an easy way to register for these tests and many others, and also a convenient place to leave reviews after you have finished the test. This issue, we have five of Microchip’s new DM320004 Ethernet PIC32 starter boards and ten of NXP’s LPCXpresso Development platforms.
Microchip DM320004 PIC32 Ethernet starter board Microchip’s DM320004 PIC32 Ethernet Starter Kit was designed to enable easy Ethernet-based development for the company’s three new 80MHz 32-bit PIC32MX5/6/7 MCU families. The new families build on the success of its 80MHz 32-bit PIC32 MCU portfolio and provide up to 128Kbytes of RAM and extensive connectivity options, including 10/100Mbit/s Ethernet, two CAN2.0b controllers, USB Host, Device and OTG, and 6 UART, 5 I2C and 4 SPI ports. These new MCU families are complemented by Microchip’s free software stacks, available in sourcecode form, making it easier for embedded designers to add connectivity to their applications. The new PIC32MX5/6/7 families are designed specifically to run more software stacks simultaneously. Designers have full access to up to 128 KB of RAM for simultaneous use with the Ethernet, USB and CAN buffers. The integrated Ethernet, CAN and USB modules have a built-in DMA interface to maximize data throughput. DESIGN WITH THE BEST at www.farnell.com
The integrated 100Mbit/s Ethernet MAC uses an industry-standard RMII/ MIII interface to low-cost, commodity Physical Interface chips (PHYs). Additionally, each MCU has a unique, factory-preprogrammed Ethernet MAC address, which simplifies the manufacturing process. Flexible, easy-to-use CAN2.0b controllers have been added to the PIC32, which use system RAM for storing up to 1024 messages in 32 buffers. Advanced filtering capabilities include user selectable filter-tobuffer mapping with 32 filters and 4 filter masks. All of these functions allow designers to easily adapt CAN communication schemes to their applications. Microchip offers free TCP/IP and USB software stacks, including full source code, to further enable easy software development, quicker time to market and lower overall costs. Available software includes two TCP/IP software stacks, along with libraries for USB Host and Device, Advanced Encryption Standard (AES), multiple file systems, advanced graphics, audio, and many other software products. Migrating software across Microchip’s 600-plus 8-, 16- and 32-bit PIC microcontroller portfolio is easy, as its development tools, USB stacks and TCP/IP stacks, span the entire range of PIC MCUs. Additionally, the new PIC32MX5/6/7 families are pin compatible with the existing PIC32 and 16-bit PIC24F USB MCU families. Example applications for the new PIC32MX5/6/7 families include: Communications (point-of-sale terminals, Web servers, CAN-toEthernet-to-USB bridges); Industrial/ Medical (automation, controllers, medical devices, security monitoring); Consumer/Appliance (audio, MP3 decoders, displays, small appliances, fitness equipment); Automotive (aftermarket, car alarms, GPS).
13 LPCXpresso Toolchain for LPC1100 Cortex-M0 Family NXP’s new, low-cost, web-enabled development tool platform, LPCXpresso is intended for the company’s LPC ARM processor family of microcontrollers. The LPCXpresso features an easy-to-use interface and supports the complete product design cycle, providing an end-to-end development solution.
LPCXpresso Targets: Users can evaluate either the LPC1100 or LPC1300 (Cortex-M3) with the included target board. The target boards share a compatible footprint with the recently announced mbed online rapid prototyping tool, enabling a common development platform across the entire NXP Cortex microcontroller range. For rapid proof-of-concepts, users can explore expanded application features with a range of off-the-shelf footprint-compatible baseboards from Embedded Artists. LPC-Link: Jointly developed by NXP, Code Red Technologies and Embedded Artists, the LPC-Link debug probe can also be disconnected from the target and used directly with the customer’s own design, using the on-board 10-pin JTAG/ SWD header. The LPC-Link uses the LPC3154 as an ARM9-based debug engine, providing an HS USB interface for accelerated code download and faster debugging experience.
LPCXpresso is designed for the beginner as well as the advanced designer. LPCXpresso users can now evaluate, explore and develop within a single easy-to-use interface while retaining all the advanced features associated with powerful and expensive tools. The LPCXpresso development platform features a powerful Eclipse-based IDE with an all-new intuitive NXPdesigned user interface, optimized Cortex-M0 compiler and libraries, LPC-Link JTAG/SWD debug probe and target boards providing users with all the tools needed to accelerate product development and time-to-market. Technical Specifications LPCXpresso IDE (Powered by Code Red): Includes a C programming environment with advanced features such as syntax highlighting, code folding, click-through links to definitions and declarations. The optimized GCC compiler and C libraries for the Cortex-M0 enables users to develop high-quality software solutions quickly and costeffectively. The IDE features several LPC-specific enhancements and is simplified for 8/16 bit users with NXP’s proprietary interface, which employs a single perspective view, enabling a seamless interconnect between code development & debugging.
Online Features: The latest version of the IDE is always downloaded from the LPCXpresso website. An exclusive LPCXpresso community forum, application resource page with up-to-date example projects, online training modules, tool wiki and support knowledgebase are some of the features that enhance the online experience for the LPCXpresso platform. There is also a built-in datasheet browser feature within the IDE environment. Expansion Options: LPCXpresso fully supports the current LPC1100 and LPC1300 families and all planned LPC1700 derivatives up to 128 KB. Code Red supports low-cost upgrade options for 256 KB and 512 KB. The fully featured Red Suite package by Code Red will support run-time execution trace and OS wizards for fast FreeRTOS configuration; in addition, Red Probe provides even higher debug performance. n
Thanks once again to Microchip and NXP for letting us have these kits for testing. If your company produces development boards and you wish to take part in the RoadTest program, please email me at firstname.lastname@example.org. I hope to see you on www.element-14. com/community/groups/roadtest soon.
Those who design very specialized boards such as those requiring extensive differential signal routing or impedance- controlled routing may need more expensive CAD tools. These tools require payment for features that may never be used, and for many licenses to keep all designs compatible. EAGLE is intended for mainstream PCB developers and is priced at levels a start-up or an individual can afford. EAGLE has 3 functional modules: Schematic Editor, Layout Editor and Autorouter. These modules are combined in different licensing options to give choices to fit any budget. The licenses also determine operating parameters within the modules. For example, the Standard license allows 99 schematic sheets, 6 PCB layers, and a maximum board size of 160mm x 100mm (single size Eurocard), whereas the Professional version allows 999 schematic sheets, 16 PCB layers and a maximum board size of 1.6m x 1.6m. All versions support a resolution of 1/10,000mm.
The powerful new EAGLE is easy to control and free to trial As higher end electronic CAD tools become more complicated with steeper learning curves, due to their increased sophistication and integration, more engineers are investing time to pick up easy-to-use, yet powerful, EDA packages like EAGLE. EAGLE’s code is low-bloat, focused and high quality. It comes with documentation: a Manual and Tutorial are in separate PDF files and there is an extensive online Help system. The PDF files are meant to be read, whereas the online Help is for quick online reference. This simplicity makes it easy to be up and running in less than a day, and working instead of trying to figure out all the intricacies of the CAD package. EAGLE’s code is high quality because it’s been developed by the same software development team for decades, who have had the time to perfect the code and develop a process for making changes to maintain the high quality. No code is released without extensive beta testing.
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Autorouter In addition to complete board autorouting, EAGLE’s Autorouter can be put into a semiautomatic mode that works in the background, as the board is manually routed. There are 2 semiautomatic modes: one will show you a trace from the mouse to the nearer connection and the other will show a trace from the mouse to both connections. As the mouse is moved, new traces are calculated and shown. The actual trace is chosen by a simple mouse click. This eliminates much of the tedium of board routing and keeps control of trace paths. In addition, EAGLE has a C-like user language to allow customization and run scripts.
EAGLE Editions EAGLE is offered in different flavors that give the users the opportunity and flexibility to first learn the software using the evaluation versions, and as the complexity of design increases, the more fully featured versions can be used to keep up with changing priorities and projects. The direct upgrade path also allows designers to seamlessly migrate to the higher end software, saving any training time and cost that have been otherwise required.
Freemium Offer Since the acquisition of CadSoft by Premier Farnell, it has introduced a more powerful “free” version –a so-called Freemium, which enables designers to evaluate EAGLE for a broader depth of applications. This is a time-limited license of what is very close to the Standard edition. Four layer boards are supported with 4 schematic sheets on a half-Eurocard form factor. The Freemium license is valid for 60 days and the activation code is available exclusively on element-14 at http:/www.element-14.com/ eagle-freemium. You are welcome to register there for your own complimentary license. Note that the license is restricted to one PC and one email address.
HOME AUTOMATION & SMART METERING
Home Automation and Smart Metering.............................................................. 16 Bringing PLC modem technologies home.......................................................... 18 Batteries for smart gas meters.......................................................................... 20 IP-based wireless sensing and sub-metering solution implementation.............. 22 High-Power PoE+ Standard Enables Smart Home Automation........................... 24 Wireless technology for the home of the future.................................................. 26 Metering beyond metrology............................................................................... 28 Smart home require smart technologies............................................................ 31 Automating the home........................................................................................ 32 Atmel and Smart Metering................................................................................. 34
Home Automation and Smart Metering Home automation has been envisaged for a number of years. Iâ€™m sure everyone has seen the television programmes that were broadcasted in the 1950s and 1960s that predicted how easy life would be in the year 2000. Robots would cook for us and clean up after us, pressing a simple button on our wristwatch would project the latest holographic entertainment, control our electronic goods. Our homes would be places of great luxury with very little work encroaching into our leisure time. Although these visions from half a century ago turned out to be false, we are now starting to head in the direction to that which was foreseen. The advent of communication technologies like Zigbee, Bluetooth, Ethernet and WiFi, combined with smart sensors and powerful processing equipment has given us an unprecedented level of control over our home environment, whether for leisure applications such as streaming audio and
video to different rooms from a distributed network of servers, games consoles, and laptops or for environmental applications like air conditioning. When we combine these technologies with Smartphones the number of options increases dramatically, allowing us to control our appliances from outside the home and even is some case, stream video or audio onto our Smartphones. Home Area Networking (HAN) is one term that you may hear a lot of in the future. Both Home Automation and Smart Metering require networking to operate; this can be wired, wireless or, more likely, a mixture of both. Wireless networking is used in many cases where it would be physically difficult or expensive to implement a wired solution. The wireless standard chosen depends on the application, for small control and monitoring applications Zigbee may be sufficient, but for
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larger media related applications, a heavier duty standard such as WiFi will be required. As many homes, especially new builds have a high-performance Ethernet network built into the structure, it makes sense to use this as the backbone of the network. As well as being able to carry high bandwidth signals for media transfer, the network can be used to power sensors or peripherals that may not be near a power source. Linear Technologyâ€™s article looks at how to design a complete PoE implementation. Security is also a major issue, with HANs carrying more information about financial information, habits, and even personal media, it is more important than ever to ensure that data is kept safe. Many of the ICs designed for Home Automation solutions include built in encryption, as well as other security techniques, as the article by Freescale inside describes.
HOME AUTOMATION & SMART METERING Smart Metering The cheap, available energy we are used to may soon seem to be a thing of the past. Rising demands from the worldâ€™s growing population and improving living standards, place a larger demand for energy than ever before. Doubts about the ability of traditional fossil fuel-based sources to cover this shortfall over a medium to long term period will put extreme pressure on our energy grids. Any shortage would almost automatically lead to quite a dramatic rise in costs for energy as well as planned outages. If the situation deteriorated, it could even lead to restricted power access. This means utility providers have to keep supplies as efficient as possible. One way of doing that is to keep a constant supply, instead of bring power stations and individual turbines/reactors on- and offline. The better visibility utility companies have over usage, the better they can plan and implement measures that will maximise efficiency. To encourage consumers to use more resources at off-peak times, the utility can use incentives such as cheap power, and/ or penalise consumers for using energy in peak hours. If utilities can accurately predict requirements, they can more efficiently manage the grid. Smart meters are an invaluable tool in this process giving accurate real-time information. Smart meters are also invaluable to consumers. If consumers have transparency about the amount of energy that is being used, where it is being used, and what it is costing, they can take action to cut usage, or plan for the most energy hungry equipment to operate at the cheapest cost times. The consumer could well be forced to choose between cost and convenience, and smart meters will be the tool that enables this choice to be an informed one.
This brings two benefits to the electronics engineer; firstly the demand for smart meters is likely to be huge, and secondly it is likely to create a demand for more power efficient equipments. This issue of
Technology First concentrates on the former of these aspects, and many manufacturers have brought in solutions specifically for the smart metering market. While Smart Metering is a necessary technology, there will be no global standard for smart metering solutions. In some areas the solutions may be quite similar and in others quite diverse. The Microchip article in this issue details a range of solutions that can be tailored to fit these regional standards using easy to integrate solutions. The technology that is driving remote metering is low power communications technologies like Zigbee, along with low power microcontrollers. As these modules could be situated remotely from a power source and therefore powered by batteries, it is important that they can remain operating alone for a number of years. Other important technologies include modems to send information to other nodes on the network, and back to the utilities, touchscreens for control and monitoring and accurate self-calibrating sensors. A winning combination The reason we have combined smart metering and home automation for the title of this publication, as mentioned above, many of the technologies are the same. In fact the two individual applications can be used together to make a powerful automated metering and control application. This type of application can be turned on and off remotely, be timed, or even switch electronics equipment off when the room is unoccupied. In the future it could even be possible that the system could monitor the energy tariff cost in real-time, and switch on power hungry equipment when the tariff drops to a lower level. In this issue Jennic takes a look at how such a system could be implemented and how to actively monitor and control the appliances that consume the most power.
HOME AUTOMATION & SMART METERING
Bringing PLC modem 18
technologies home Source: Texas Instruments
Smart Grid Deployment needs are boosting research, effort and development into PLC (power line communications) modems. With more than 200 millions smart meters to be deployed in Europe alone, electricity meter manufacturers are looking for cost effective, reliable and flexible communication solutions for the move to Smart Electrical meters. These smart E-meters are capable of two-way communication outside of the home back to the utilities, and inside the home to monitor devices such as thermostats, in-home displays and smart appliances.
Approximately 50% of the communication media from medium voltage to low voltage substations and to the electrical meter will be power line communication in Europe. Interest is also growing worldwide in regions such as Asia and South America, where adopted solutions may differ from each other. Interestingly enough, with smart metering paving the way to large scale deployment, there are many other applications connected to the electricity grid looking towards this technology and concept. Many of these applications will belong in the Home Area Networks area, and the good news for developers is that there is a path for R&D re-uses to accelerate the deployment of PLC modem technologies, thanks to the Smart Meter effort.
Zoom on Smart Meters PLC technologies There is no unique worldwide solution for PLC solutions in smart electrical meters, as there is a large variety of requirements and options for each individual country or utility. These options include modulation, protocol, bit rate, robustness and many others. Developers need flexible solutions that can cope with each local challenge without building their expertise all over again for each scenario. TI has been spending a considerable amount of effort on PLC communication solutions for smart electrical meters and is providing the flexibility to cope with this challenge. System performance can be optimized by altering the system architecture, therefore DESIGN WITH THE BEST at www.farnell.com
HOME AUTOMATION & SMART METERING understanding what type of modulation or standard needed is important to the system design. Ideally, a single hardware implementation that can accommodate multiple modulation schemes, such as OFDM or FSK, and different standards such as S-FSK or the Low Frequency Narrow Band OFDM, such as G3 and PRIME, would be the best solutions. This flexibility is possible by breaking the system down into compatible building blocks. At the highest level these building blocks are made of a programmable microcontroller, a tunable analog front end (AFE), and a flexible software suite. A high performance programmable 32-bit microcontroller provides the processing power needed to implement algorithms required by the different modulation schemes. A tunable AFE provides the interface to different frequency bands required by each standard. Lastly, and most importantly, the software suite integrates these building blocks by providing the developer with libraries, APIs, and code to achieve the most out of their system. Texas Instruments has the right 32-bit MCU, analog, and software solutions to allow the customer quick development and evaluation of PLC technologies. Among the many standards emerging today, TI has developed hardware and software for customers to evaluate both Low Frequency Narrowband OFDM and SFSK implementations. At a high level, the PLC implementation, regardless of standard, contains the same basic components. The heart of the solution is the C2000 32-bit microcontroller. The ability to program this high performance MCU for emerging standards gives the flexibility customers demand in this emerging market. Positioned as an interface between the microcontroller and the power grid, the AFE circuitry is responsible for filtering the communications signals for compliance with different transmission standards, including CENELEC. This is done with the help of high performance analog components, such as the OPA564 and PGA112. There are many hardware tools to evaluate PLC solutions today; TI’s prime development kit is based on the TMS320F28335 MCU. This kit was designed to use the C2000 Control Card, which allows the migrations of solutions to other MCU products within the control card platform. The AFE has also been modularized to allow other AFE implementations with less strict out of band transmission requirements. Software for the PRIME solution has been developed on top of the “PLC Suite” libraries, which provide full API accessibility to each of the software layers. This software suite has broken the complex tasks of the software into multiple compatible layers with the ability to communicate between one another: PHY, MAC, convergence layer and application layers (See figure below.) The modular libraries allow the developer to add and/or remove functionality to customize the solution that fits specific needs. Beyond the Smart Meter: Industrial application As stated previously, PLC technologies are going beyond smart electrical meters. Other applications connected to the grid will use the pioneering work that has already been done on smart meters. Plug-in electrical vehicles and solar inverters, which both represent a distributed load on the grid, are two strong candidates for this technology, and there are many initiatives ongoing already at a worldwide level. Plug-in electrical vehicles (PEV) exchange information with the charging station using the electrical connection required for the charging sequence, hence are the natural choice of power line communication. In Europe, the Cenelec A band is being exclusively reserved for utilities; the PEV power line will have to use other bands like B or C. Developers could ideally take the benefits of the knowledge infrastructure put in place for smart meters, and use the investment made on low frequency narrow band OFDM, adapting the solutions to their needs. Texas Instruments’ flexible software programmable solutions can easily be adapted to match this goal. The current C2000 32-bit MCU will cover A, B, C bands, as well as the full FCC band, for worldwide coverage with a simple software upgrade. The analog front end needs to
be adapted, but this has been taken into account in TI’s development kit, which has the AFE flexibility to avoid major redesigns to cope with the different scenarios. In addition to this, the C2000 32-bit processor is very popular for energy conversion related applications and many designers have experience of its use. Moving to a communication application usually starts by adding one PLC module and leveraging experience on tools and software. Future HAN applications using PLC are yet to be precisely defined, but will not be restricted to solar power or hybrid vehicles. Lighting is also a prime contender to take advantage of this new technology. TI has a strong experience in HAN technology, with a large portfolio of low-power RF radio transceivers or RF system on-chip (SoC), like the popular CC430 sub 1GHz device or CC2530 ZigeBee. The full challenges of PLC modems for HAN are still being fully identified. At this stage, it is clear that solutions will have to be scalable and need to address various system cost constraints depending on the end application. Starting from a proven, flexible solution will allow developers to reduce development time and accelerate time to market. This is possible today with TI’s software flexible Power Line Communication solutions. n
HOME AUTOMATION & SMART METERING
Batteries for smart gas meters
Batteries are the lifeblood of a wireless device, providing the essential power required for reliable data collection, storage and communication. Specifying the right battery is essential, especially for wireless communication modules designed for the long-term, where battery replacement is costly and life cycle costs of the equipment are crucial.
This decision-making process is complicated by the breadth of choices between competing chemistries such as alkaline, carbon zinc, zinc-air and lithium, and by the fact that it is often difficult to differentiate a superior quality battery from an inferior counterfeit item. So getting it right demands thorough product knowledge and due diligence to ensure that the optimal power management solution has been specified. Reviewing options Application-specific requirements often dictate the solution. For example, consumer alkaline cells can suffice for applications requiring only a few months of service life in a moderate temperature range and where battery replacement is relatively simple due to easy accessibility. While inexpensive and readily available, alkaline batteries are ill-suited for applications that require extended service life Li/SOCI2/w/Hybrid/ Li/SOCI2/ under extreme temperatures. Li/System Layer Capacitor Choosing the optimum power management solution begins with a careful evaluation of power and performance requirements, from which design engineers can compare competing chemistries, based on a prioritized checklist of desired attributes such as voltage, capacity, size, weight and/or special packaging requirements, expected service life, temperature and/ or environmental issues and cost. Special requirements such as the need for high current pulses or a high discharge rate should also be considered.
Lithium Batteries for long term applications While primary lithium batteries lack the “media buzz” associated with rechargeable batteries, they offer dynamic opportunities within growth markets such as smart grids, utility automatic meter reading (AMR), wireless mesh networks, system control and data acquisition, data loggers, oceanographic, emergency, and safety equipment, as well as other remote sensing devices where recharging is not practical or even impossible. Lithium is the preferred choice for utility meters due to its intrinsic negative potential, which exceeds that of all other metals. Lithium is the lightest solid metal, and offers the highest specific energy (energy per unit weight) and energy density (energy per unit volume) of all available battery chemistries. Lithium cells, all of which use a non-aqueous electrolyte, have normal OCVs of between 1.5V and 3.6V. The absence of water also allows certain lithium batteries to operate in extreme temperatures (-55°C to +150°C).
Li/SOCI2/ Spirally Wound
Energy Density (Wh/I)
Performance at Elevated Temp.
Performance at Low Temp.
Self Discharge Rate
-55°C to +100°C
-55°C to +150°C
-55°C to +85°C
-55°C to +60°C
O°C to +60°C
Comparison Table: Batteries for wireless devices
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HOME AUTOMATION & SMART METERING Despite the popular misconception that all lithium batteries are essentially equal, the lithium family of primary batteries is actually quite diverse. The choices include poly carbon monofluoride (Li/CFX), manganese dioxide (Li/MnO2) and lithium thionyl chloride (Li/SOCl2). Each chemistry offers unique advantages and disadvantages, so trade-offs are inevitable. Poly carbon monofluoride (Li/CFX) and manganese dioxide (Li/MnO2) are best suited for applications that do not require a long operating life or possible exposure to extreme temperatures. However, when extremely long battery life, extended temperature range and reduced battery size and weight are important considerations, the lithium battery of choice is lithium thionyl chloride (LTC), which is available in two styles: bobbin or spirally wound construction. Bobbin-type versus spirally wound construction Both spirally wound and bobbin-type lithium thionyl chloride batteries use a non-aqueous electrolyte, resulting in relatively high impedance. Spirally wound cells reduce this impedance by increasing the surface area of the anode. This implies more inactive materials such as separators, substrate and current collectors, whereby overall performance is reduced and energy density is lowered. Also, operating life is shorter as extra surface area leads to more self-discharge. As a result, spirally wound LTC batteries deliver only 800Wh/l energy density with a temperature range of -55ºC to +85ºC and a maximum service life of about 8 years. In contrast, bobbin-type LTC cells are capable of delivering far higher energy density (1,420Wh/l), have more capacity and are able to withstand extreme temperatures (‑55ºC to +150ºC). Due to low annual self-discharge (less than 1% per year), they also offer an extremely long service life – more than 25 years according to customer testimonials. While the theoretical service life of a bobbin-type lithium thionyl chloride battery is over 20 years, actual service life varies based on the self-discharge rate, which is governed by the chemical composition of the electrolyte, the manufacturing processes used, as well as mechanical and environmental considerations. Battery performance and self-discharge can also be negatively affected by high levels of impurities in the electrolyte, as well as by impedance resulting from the internal resistance created by the electrolyte, the anode
and the cathode. Experienced battery manufacturers can control impedance by blending special additives into the electrolyte. Lithium thionyl chloride batteries have a proven track record for utility metering applications. Since the 1990’s, these batteries have been used in the E6 electronic gas meter. Also, in 1984, Hexagram (now Tadiran LTC Batteries Aclara), introduced their first automatic meter reading (AMR) devices for the gas and electric utility market, which was powered by AAsize lithium thionyl chloride batteries. Over 3 million of these devices have been deployed worldwide, and virtually all continue to operate on their original batteries after 25 years. Long-term reliability is especially critical to the utility industry, as extended battery life translates into higher productivity and profitability by eliminating the need for system-wide battery change outs. High current pulse “hybrid” solutions In addition, there are a growing number of applications that require high current pulses, presenting technical challenges to both spirally wound and bobbin-type lithium batteries. Typically, these applications involve low continuous current (or no continuous current) coupled with high pulse currents of up to several amperes. Devices requiring high current pulses must be carefully designed to extend battery life. For example, these devices are often programmed to operate in multiple modes: a sleep or standby mode, where power consumption is nil or a low background current; a measurement or interrogation mode, where the unit requires a few hundred milliamps of energy; and a transmission mode that requires high current pulses before returning to sleep or standby status. Spirally wound lithium thionyl chloride batteries deliver the energy density required by high current pulse applications, but lack the required capacity and have a comparatively high rate of self-discharge, which limits their long-term operation. Another fact is that the internal resistance increases with depth of discharge, thus also limiting battery life of this style. Bobbin-type cells have the ideal capacity and energy density, but only allow low current pulses due to their low rate Tadiran’s PulsesPlus™ technology design. To overcome this, engineers at Tadiran developed PulsesPlus™ technology by combining a bobbin-type primary cell with a patented high rate, low impedance HLC (hybrid layer capacitor) to deliver extremely high currents with an excellent safety margin. The rate at which energy can be stored by the HLC varies from 280As with smaller HLCs, to 1120As with larger size HLCs. Variations of this hybrid technology have also been utilized to provide short duration high rate power for military and medical applications. Evaluating Battery Suppliers Once the right battery chemistry is chosen, design engineers need to perform due diligence to verify that the lithium battery they have specified can deliver as promised. With the rapid growth in knock-off products now flooding the marketplace, vigilance is required to ensure product quality and authenticity, including 100% product traceability back to the raw materials. As part of the vendor selection process, it is therefore recommended that potential battery suppliers be required to provide a list of customer references along with fully documented and verifiable test results for parameters, such as battery pulse, low temperature pulses, discharge and repeatability. Faithfully applying these and other common sense practices during the vendor selection process will help ensure years of trouble-free battery performance. n
HOME AUTOMATION & SMART METERING
IP-based wireless sensing and sub-metering solution implementation Source: Arch Rock
Corporate sustainability policies associated with national and regional regulations and mandates are accelerating the adoption of green building practices in commercial, industrial and institutional contexts. However, the implementation of these energysaving principles and practices has been hampered by a lack of fine-grained information that allows facility managers to efficiently manage energy bills, without impacting the productivity or necessitating prohibitive and invasive installation steps. The critical factors influencing the cost of energy consumption are captured by utility billing mechanisms that include incentives and rebates on the one hand, and penalties and prohibitive rates on the other.
Today, facilities and IT managers are keen to continuously benchmark, calibrate and visualize the energy consumption and environmental behavior of buildings, without jeopardizing the existing stability of the facilities and not incurring invasive and costly instrumentation steps, as would be the case with wired and AC-power dependent devices. By using Arch Rock’s Energy Optimizer (AREO) solution, facilities or IT managers can quickly and easily deploy a IP-based wireless sensing and sub-metering solution that provides fine-grained visibility and continuous energy monitoring through an energy visibility portal.
AREO relies on a PhyNet infrastructure of standards IP-based and web services-based elements that provide reliable wireless mesh networks, data backhaul, collection, management and export, turning the sum of individual data points generated by the deployed Sensing Nodes into valuable time series of information that can be exploited by application layer software for visualization and analysis.
These infrastructure elements include: • • •
IPrelay Node PhyNet Router PhyNet Server
Applications on Energy Portal
Once all sensing and infrastructure equipment is in place and configured, the user can focus on configuring the energy portal to suit the energy manageability goals and business, such as using meaningful names to make identification easy.
events against their energy impact, such as observing the energy-saving effect of changes in the set point on the HVAC thermostat systems by a few degrees, or the effects of new idle power-off strategies. These planning-oriented capabilities are of value towards avoiding utility billing penalties, and towards being ready to participate in incentive-carrying loadshedding programs such as “Demand/ Response”, while realizing the energy savings in ways that are least disruptive to the business and operation of the building. The energy portal is offered in “Software as a Service” form, in which the user accesses the private portal via secure web access, or as an on-site appliance located on the corporate network. Data can then be transmitted fully protected using the standard IPsec encryption mechanisms for securing Internet Protocol traffic over private or public networks.
Equally, the user can configure energy consumption or maximum load goals against which the building performance can be tracked and notices and alerts generated when appropriate. Event logs can also be entered to match Figure 1 AREO in action -- Commercial office building
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HOME AUTOMATION & SMART METERING Business Benefits
As in any change management process, it is important to record the initial baselines and to set control points to evaluate the benefits of specific actions in order to quantify full benefits. In light of the various capabilities previously discussed, one or more of the following benefits can be realized: • Financial savings – After defining a desired threshold of dollar or energy savings or power peak reductions from the initial baselines of these parameters, it becomes easy to measure progress against goals. Several studies [FEMP] have shown that as much as 8%-12% could be expected through awareness of usage and simple actions • Capacity planning – By following the electrical branch circuits and measuring electric consumption and real-time peaks on each sub-branch of interest, circuitlevel sub-metering instrumentation disaggregates energy consumption into its constituent "spatial" or "functional" components, in addition to its “temporal” patterns: a given floor or a wiring closet or even a section of the lab, and how their energy footprint ebbs and flows during the hours of the day or days of the week or the seasons of the year. Once a facilities manager knows where and when power was drawn and energy consumed, and how energy has peaked and ebbed in the facility over the hours and days, he or she has a rich picture of the key areas on which focus should be applied, in order to achieve direct savings or take advantage of incentives, while maintaining “service levels” for the desired levels of safety, comfort, activity and productivity throughout the facility. • Regulatory mandates – It is generally agreed that commercial and light industrial buildings are responsible for at least 40% of energy use in most countries [WBCSD]. Through various national mandates (e.g., US EISA 07 and EPAct 05) in the US, Europe, Japan, China and elsewhere – or local and regional mandates (e.g., California AB32), explicit schedules to reduce energy consumption or to increase energy efficiency of the facility’s output are defined, often requiring sustained year-over-year efficiency improvements over long periods. Existing, as well as new commercial offices, have to comply with those regulations. But without real data, it can be difficult to baseline a building, not to mention to track its evolution against the desired efficiency goals over time, in a way to anticipate whether goals will be met or not, while something can still be done about the outcome. By analyzing the data from AREO, it becomes possible to understand a building’s behavior and demonstrate that the mandate has been achieved, with
a direct result of increasing the lifetime of your assets or reducing operating expenses, or both. • Sustainability policies – most if not all enterprises and public administrations have defined sustainability policies or programs. But despite the messages advertised on information panels or company annual reports, it may be difficult to get all employees fully engaged in such programs. By showing real-time data from the energy portal, an AREO deployment can help in the development of a “community spirit”.
Achieving energy efficiency benefits start first with the ability to deploy instrumentation that generates detailed visibility into the patterns of energy consumption and the associated ambient
AREO energy portal turn the raw sensor data points into actionable information, enabling the extraction of new insights, patterns and associations in order to save energy. Last but not least, users can often obtain their energy data in more ways than any one vendor-provided analysis tool can provide. It is therefore critical that the instrumentation system be built with endto-end open standards at the network layers and application and data access layers. With its standards-based open IP networking throughout, and its open and flexible data export mechanisms, AREO allows users to benefit from its analytical capabilities, while allowing them to put their energy “in broader context” by applying their preferred IT analysis tools, not only to the data generated by AREO, but also to combined
Figure 2 AREO energy consumption display
and environmental conditions. AREO’s ultra low power wireless network, PhyNet technology, embedded in its suite of energy and environmental sensors, presents facility managers with the option of achieving detailed visibility, without the costs and effects of previous wiring-based highly invasive instrumentation systems. Next, the visualization, analysis, goal setting, and tracking capabilities of the
data sets where AREO-generated data can be “mashed up with” and correlated against relevant enterprise data. Examples include activity levels or occupancy outside weather data, thus maximizing the value that is latent in the facility and energy data, by enriching it with business-specific
HOME AUTOMATION & SMART METERING
High-Power PoE+ Standard Enables Smart Home Automation Source: Linear Technology
Power over Ethernet (PoE) was defined by the IEEE 802.3af task force in 2003, and has enjoyed industry-wide acceptance. This standard defined nominal power delivery at 12.95W, which was more than adequate for the early adopter applications, such as standard VoIP phones, security cameras and wireless access points (WAPs). Today, network switches from all the major manufacturers can be purchased with PoE-enabled ports, and with this infrastructure now in place, the demand for additional features and higher power has increased.
In 2006, to combat the limited power budget and open PoE to new markets, a group from the IEEE started a new task force to explore raising the power limits of this international power standard. Thus was born the IEEE 802.3at task force and the fully ratified PoE+ standard. The PoE+ standard enables a whole new breed of power hungry devices from longer range WAPs, full-featured video phones, video teleconferencing stations and high performance pan-tilt-zoom security cameras, along with home, hotel and conference room automation. One of the areas that required careful engineering design in the standard was the new classification mechanisms that would be used to allow the Power Sourcing Equipment (PSE) and Powered Devices (PDs) to mutually identify each other. With this mutual identification, came the ability for PSEs to properly power both .af (also known as Type 1 hardware) and .at (Type 2 hardware) PDs, as well as the ability for .af PDs to be powered by .at PSEs and for .at PDs to know if they have the full power that their higher loads demand. Every combination needs to have a well-defined and consistent behavior, so that interoperability within the 802.3 standard is maintained. This mutual identification has been implemented in 802.3at with the use of a more elaborate hardware classification mechanism, along with a new data-layer mechanism. 802.3at hardware classification is called 2-event classification (also known as ping-pong) and involves the PSE essentially repeating the 802.3af voltage probe twice. Each voltage probe of the PD results in
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a pulse of current being drawn (see Figure 1) which corresponds to a particular power level. To begin, the PSE asserts a voltage pulse in the range of 15.5V to 20.5V on the data or spare pairs. The PD responds with a current of up to 40mA, which conveys one of four power classes to the PSE. The double pulse is a signal to the PD that the connected PSE is indeed a high-power PSE able to source the higher power levels associated with 802.3at power. The 802.3at PD responds with a class 4 current, thereby telling the PSE that it is a high-power PD requiring the full power available. The layer 1 classification method in 802.3af was an optional method for the PSE to query the PD to determine the PD power needs. However, in the 802.3at specification, a Type 2 PSE is now mandated to perform, at a minimum, the single event hardware classification.
LLDP In addition to the upgrade in hardware classification, the PoE+ task force defined a new data layer (layer 2) classification known as the Link Layer Discovery Protocol (LLDP) for communication between the PSE and PD. Once the power link is established, the PSE and PD can use LLDP to determine the power needs of the PD. The use of LLDP allows the PSE to query the PD repeatedly and determine the status of the PD and its power needs. With this mechanism, it is now possible to implement dynamic power allocation where the PSE can continuously allocate power to the PD in 0.1W increments and the PD can request, and then subsequently relinquish, power. Communication over layer 2 enables advanced
HOME AUTOMATION & SMART METERING 30W+ with up to 94%, enabling proprietary power levels and unlocking PD features beyond that of the PoE+ standard. Reliability is reinforced by integrating a rugged 100V Hot Swap MOSFET, which isolates the PD controller and DC/DC converter during detection and classification, while providing 100mA of inrush current for smooth power-up transitions with any PSE.
Figure 1 – 2-Event Classification and Link Layer Discovery Protocol
features to poll for more information, such as peak power, average power and duty cycle. This new dynamic power allocation is certain to become an important feature, as systems move toward a greener power environment. LLDP is an optional classification mechanism for the PSE, but is required to be implemented by the PD. If the PSE only performs a single event classification, then the PD may negotiate higher power via the LLDP protocol. Figure 1 shows both classification methods used in PoE+.
The accuracy of the LTC4266 affords the use of low-value sense resistors and, more importantly, low RDS(ON) MOSFETs when managing line currents and voltages. Values can be as low as 0.25Ω for the sense resistor and 0.09Ω for the MOSFET, providing a maximum total channel resistance that is half that of other
Two versions of the LTC4269 are available in order to optimize PD designs. The difference between both versions lies in the specific switchers used. The LTC4269-1 integrates a synchronous flyback controller, while the LTC4269-2 integrates a synchronous forward controller. The flyback converter provides a low part count design, with the advantage that additional outputs can be obtained by simply adding more windings, while the forward controller provides slightly better efficiency over the flyback at higher load currents. In both cases, synchronous rectification provides the benefit of higher output power, increased conversion efficiency and improved crossregulation in applications with multiple outputs. Furthermore, in low-noise system designs, the controllers can be synchronized to an external oscillator.
Current capping For PoE systems, there are two distinct locations where power is defined: at the PSE output connector and at the PD input connector. One of the more important developments on the PoE+ specification is the capping of the current to 600mA. A PSE must now be able to continually source at least 600mA with a minimum output Figure 2 – LTC4266 Quad-Channel PoE+ PSE Controller and LTC4269 PoE+ voltage of 50V. This translates to a PD Controller with High Efficiency Integrated Switching Regulator PSE output power of 30W. The cable resistance is modeled no larger than It is also worth noting that the LTC4269-1 12.5Ω, resulting in 25.5W available power at the PSE controllers. As a result, heat dissipation and LTC4278 incorporates No-Opto feedback PD connector. It is necessary to take into account is significantly reduced, allowing designers to topology to provide full IEEE 802.3 isolation, the 48V conversion efficiency so that in the end, easily and reliably use the LTC4266, without a without the need for optoisolator circuitry. there is about 24.6W available at the PD load. heat sink if desired. The benefit of using external This avoids the disadvantages of implementing MOSFETs is if a port fails due to a MOSFET A new solution optocoupler feedback, including variable failure, the failure will not “domino” and cause Linear Technology’s LTC4266 quad PSE loop gain due to optocoupler tolerance, high adjacent channels to collapse. controller and associated LTC4274 single-port temperature sensitivity and higher cost. The Linear Technology has a family of IEEE 802.3at version are fully compliant with IEEE 802.3at, traditional optocoupler and shunt regulator compliant PD offerings that not only offer a and are backward compatible with the popular used in the feedback loop are replaced by an robust front-end for withstanding the high 802.3af compliant LTC4259A-1. Not only do additional winding on the existing transformer voltages of a PoE+ system, but also offer the they provide PDs with power levels mandated for improved regulation, efficiency and a simpler highest efficiency solutions. The LTC4269 is a by the new standard, but they are also backward circuit. full featured and fully compliant IEEE 802.3at compatible with the original PoE standard, In conclusion, PoE+ brings more power and PD controller with an integrated switching allowing users to mix and match up to four PoE regulator, offering auxiliary support down to 16V. better classification techniques to an already and PoE+ PDs on the quad device. The LTC4266 established industry of PoE networks, with For auxiliary support down to 10V, the LTC4278 delivers PoE+ compliant 30W, or higher power higher power level that will enable high level can be used. Although 802.3at caps the power for proprietary systems of up to 50W over two of control and functionality in home, hotel and delivered to a PD at 25.5W, the LTC4269 does not pair, or 100W over four pair. have a current limit and can comfortably source conference room automation systems. n
HOME AUTOMATION & SMART METERING
Wireless technology for the home of the future Source: Jennic
The idea for intelligent homes has been around for many years, yet despite the efforts of many engineers, home automation is limited to a timer on the oven for most people! Ideas such as an Internet connected refrigerator have been disappointing failures, and some commentators have begun to wonder whether home automation is simply a solution for a problem that doesnâ€™t exist.
Recently several trends have created demand for more intelligent control within the home. The biggest factor has been the increasing awareness of the financial and environmental costs of energy consumption, and the wish of both consumers and government to reduce power consumption within the home. Legislation is being introduced in many countries to require that consumers are made more aware of the amount of energy they consume, while utility
companies are also required to show they are investing in projects to increase efficiency of energy use. These demands have driven the creation of a new category of products: smart meters that provide remote display of energy consumption. In many countries such as the UK, consumer adoption of these smart meters is exploding, driven by increased interest in reducing an individualâ€™s environmental impact, and in some cases, significant subsidies that allow these products to be given away with certain electric tariffs. Utility companies can also reap cost savings by including wireless automatic meter reading (AMR) functionality, which cuts the cost of recording usage and billing customers. A logical extension to todayâ€™s smart meters would be active monitoring and control of the appliances that consume the most power within the home. This would not only offer savings to consumers, but would allow the creation of a smart grid, where energy-hungry appliances such as clothes dryers only operate at times of low demand. As the capabilities of these systems expand, it is likely that additional functionality would be added, such as for the monitoring of smoke alarms and security systems. In order for a smart grid of this nature to be realized, the individual appliances need to be networked together in some way.
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Although there is now greater demand for intelligent home networks, engineers still need to overcome the challenges of creating a simple, reliable and cost effective connection between the devices on the network. Running cables in such systems is impractical in a domestic environment, and therefore this connection must be wireless. Although many consumers now have wireless broadband routers, providing a home WiFi (IEEE 802.11) network to an existing infrastructure is a poor solution in most situations. An 802.11 transceiver draws a significant amount of power and the standard does not easily allow for devices that spend most of the time in sleep mode. This makes WiFi impractical for battery-powered devices within the home. WiFi is an IP network, which can make adding new devices to the network complex. A far better solution for most smart energy and home automation connectivity is IEEE 802.15.4. Although more recent than WiFi, this standard and the protocols that run on top of 802.15.4, such as ZigBee, are now mature, and provide an excellent wireless platform that will drive the development of innovative new home automation products. This technology ensures reliable communications in a domestic environment, while consuming very little power, enabling a battery life of up to 10 years.
HOME AUTOMATION & SMART METERING Protocol
Table 1: Comparison of low-power wireless communications stacks
The 802.15.4 standard is a very flexible platform, giving developers a wide range of communication stacks that can be run. Simple networks can be developed using a simple proprietary protocol running on top of 802.15.4. For many consumer applications requiring interoperability between products from different vendors, protocols such as ZigBee provide the functionality and standardization required. Although ZigBee is perhaps the bestknown of the standards built upon 802.15.4, it can be overkill for some home automation applications, such as where manufacturers don’t require interoperability with products from other vendors. Semiconductor vendors have therefore filled this need with off-the-shelf protocol solutions that eliminate much of the overhead of a complex standard such as ZigBee. Perhaps the best known of these protocols is JenNet from Jennic. JenNet provides a self-healing network that can scale to thousands of devices – more than enough for domestic applications. More importantly the protocol offers designers a much simpler stack with an easyto-use API that reduces development cycle times; in fact there is even an AT-JENIE API that allows software to interact with Jennic’s network protocol stacks, microcontroller peripherals and system services using an AT-like command set. The stack is also available free of charge, adding no cost to the final product, and potentially reducing development costs by providing a simple API that allows rapid development of software. Another vital decision is the selection of a hardware vendor. Any consumer product faces intense pricing pressures, therefore engineers must minimize the component and manufacturing cost. A single chip solution not only offers potential BOM savings, but also reduces the size and manufacturing cost of the final solution. As many vendors of low
power wireless solutions are generic microcontroller vendors, however, most solutions available require two devices: an application specific device providing the wireless communications and a separate microcontroller for the application. Jennic offers a more efficient approach: a 32-bit wireless microcontroller that integrates the 802.15.4 MAC and PHY to provide an efficient and cost-effective single chip solution. The Jennic devices offer engineers the memory footprint and higher processing performance for the most demanding applications such as those using ZigBee PRO, while offering extremely cost-effective solutions that would be ideal for home automation applications. In all cases, the integrated 32-bit RISC processor provides the horsepower to run both the communications stacks and the application code on a single device.
peripherals, the device also includes a 4-wire digital audio interface that will connect directly to mainstream audio CODECs, low-power sleep counters designed for pulse counting in automatic meter reading (AMR) applications, and a Time of Flight (TOF) ranging engine for use in location aware systems. The RF aspects of a product design require specialist RF design expertise that may not be a core competency of a company making consumer products. Furthermore, the testing and certification required for a new design can be time consuming. With the consumer market demanding short development timescales, developing bespoke RF circuitry can introduce significant risk to the project. The best solution is the use of off-the-shelf modules that allow fast prototyping and a quick, low-risk route to production. Jennic offers a range of modules that allow engineers to implement wireless communications using modules that are known to be able to meet legislative requirements. Using modules not only shortens the time to develop the product, but also nearly eliminates the chance of the product failing qualification, which would introduce further delays and incur more development cost.
Figure 1: JN5148 Block Diagram
Figure 1 shows a block diagram of the JN5148, the latest device in the Jennic product range. In addition to providing a 32-bit RISC processor that features improved coding efficiency and up to 32MIPs performance, the JN5148 also includes a fully compliant 2.4GHz IEEE802.15.4 transceiver, 128kB of ROM and 128kB of RAM to support both the networking protocol stack and user application on-chip, and a rich mix of user peripherals. In addition to various ADCs, UARTs, timer/counters and other general-purpose microcontroller
Although the promise of a complete home automation system is still some way off, consumers are already using simple products such as smart meters that are laying the foundations for more comprehensive solutions. By choosing the right approach to short range communications, and a vendor that can both reduce risk and provide scalability, companies can create products that meet the needs of today’s consumer while providing a platform on which tomorrow’s solutions can be built. n
HOME AUTOMATION & SMART METERING
Metering beyond metrology Source: Freescale Semiconductor
Smart meters provide many advantages to consumer and utility companies, such as recording actual cost of energy use, real time updates on electricity tariffs and the option to have tariffs dependent upon power usage. Despite these advantages, the transition from a traditional meter to a smart meter presents a number of challenges, which require a well-designed product, capable of supporting advanced functionality. A key purpose for the development of smart meters is to modify consumer behavior towards power usage, drawing attention to the cost of their electricity, gas and water usage. In the future, meters will be expected to handle more than just a manual reading every 3 months, so as to deliver a service to the consumer. The “smart” in smart meter refers to the added data analysis capability, the upgradeability in the field of the meter, the connectivity within the home or building, as well as increased security for the utility companies utilizing the design. Figure 1 shows a schematic representation of a smart meter. This article explores these challenges in detail, addressing the key issues a smart meter developer must resolve in order to provide a competitive product in a rapidly growing market. The design of the smart meter is shifting away from being simply a measurement unit, to becoming a data source. With this change, the smart meter must support an increasing range of functions that may change over time, as the demands on our energy use tighten.
for the smart metering market is the MCF51EM256, providing a special set of features, such as ultra low power, real time clock with the capability of adjustment, dual flash arrays for field updates and antitamper and security functions. Power measurement, often referred to as metrology, is performed with two dual Analog to Digital Converters (ADCs). They run conversions at 2MHz with an effective number of bits (ENOB) of 14.5 bits with the built in 32 result averaging hardware, thus removing some computation burden from the CPU. Making simultaneous measurements from voltage and current sensing requires
A recent trend in metering microcontrollers is the move to 32-bit CPUs to support the growing computation and communications needs. The ColdFire V1 is a lean, yet high performance version of the 68K based ColdFire family supporting bus speeds up to 50MHz, while retaining tight code density and low power dissipation. A specific version created
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Figure 1 – Schematic of a smart meter
accurate control of any phase delays in the measurement chain. Shunt resistors can suffer from minor phase delays at low currents, but current transformers have a far greater phase shift, sometimes more than 4 degrees. A delayed trigger for measurement by the ADC can allow the ADC used for voltage measurement to then make a current measurement, thus reducing the need for additional ADC modules. A special timer module, called the Programmable Delay Block (PDB), very cleverly takes care of this by providing a delayed trigger for a current measurement by the ADC, following a successful measurement of the voltage without CPU intervention. The Freescale poly phase reference  has two different current transformer types to illustrate the value of the PDB. With timer granularity as low as 40ns and prescaler settings to allow for adjustment to the sample periods, it is possible to compensate for a wide range of phase delays. An example of 4 degrees of phase compensation results in a delay of 185μs with a PDB timer resolution of 1μs. Normally measurements are taken 64 times per mains cycle (every 260μs for 60Hz or 312μs for 50Hz), so the same ADC channels can be reused for the current measurement following a voltage measurement. The PDB thus removes a significant burden from the CPU and improves utilization of the ADC module. The CPU performance is important to support a wide range of calculations required of a smart meter. The following routines are required for a 3 phase, 4 wire meter: • Line to Neutral Voltages • Phase Currents & Average Current • Active Power & Net Active Power
HOME AUTOMATION & SMART METERING • • • • •
Reactive Power Apparent Power Power Factor Frequency Energy Calculations (Active, Apparent & Reactive) • Voltage Unbalance • Current Unbalance A fast multiply – accumulate is essential for such an algorithm and this favors the 32 bit CPU architecture of the ColdFire V1, while also minimizing power consumption during the calculation. Application performance analysis shows that the MCF51EM256 takes just 60% of its capability to perform the full suite of poly-phase power calculations mentioned above. With the bus clock management options, it is possible to lower the CPU bus clock to reduce power consumption should that be a benefit for the smart meter. Security is a key feature of smart meters that must be considered with care. The investment in the smart meter means that field updates are a potential need over the 15 to 20 year lifetime of the application. The ability to run from one flash array while re-programming the other array, allows the MCF51EM256 to continue to perform metering and communications functions as normal, while uploading new routines. Data rates for meter communications can be very low, often in the range of hundreds of bits per second, so it is not possible to stop metering functions during this time. Protection is provided through a memory manager and allows transfer to the newly programmed code when validated and then provides the user with an option to erase or retain the previous executable code. Security features in the debug environment restrict any code access through hardware and password protection schemes and force flash erasure before the debug environment can be activated. Other forms of security lie with runtime and physical security. Anti-tamper is a means of detecting that a pin on the device package has been disconnected from the printed circuit board. Placement of these pairs of anti-tamper pads among the active pins of the device provides immediate recognition of a physical attack on the microcontroller. Dedicated pins with hardware detection force a bit in memory to trigger an interrupt and allow communications software to alert the utility company of the intrusion and allow access to the time stamped event details when reconnected. The code on the microcontroller can determine if this warrants erasure of the flash or
another extreme action to prevent theft of firmware of modification to the meter device. A key feature of the tamper detection circuit is that it cannot be cleared until both the VDD and battery supplies are disconnected. Reconnection of the supplies forces optional security functions to be called, thus preventing a return to correct operation of the smart meter.
available on smart meter products. For the meter itself, there is a large segment LCD for tariff, energy use and date/time. The MCF51EM256 supports up to 288 segment LCDs with options for 4 or 8 backplanes, to suit various region needs while also reducing power consumption. A fully operational a 3 phase electricity meter reference design  has been developed by Freescale using the MCF51EM256 (see Figures 2 and 3), and performs full metrology and IEC61107 within 128kbyte of code. The reference design has been shown to meet MID class C rating for a 10-60A meter with 0.5% accuracy and supports the following standards: optical port as per standard IEC 62056-22, meter standard compliance IEC 62053-11, IEC 62053-22, IEC 62053-23 & IEC62056-21.
The battery backup for the real time clock is essential to providing a time of day, even when the mains supply is removed so that tariffs are always applied at the correct time of day even on reconnection. The real time clock must remain operational for up to 10 years on a single button cell without connection to the mains, and is achieved through dedicated low power design. In STOP mode, the robust real time clock module consumes less than 2μA and maintains real time clock accuracy below 2PPM (one minute accuracy per year) with once per hour clock adjustment. The accuracy of the clock is adjustable in increments of a single clock pulse at any time. Typically, the on board temperature sensor will be used to determine temperature drift, which is the most critical parameter for crystal accuracy and Figure 2 – 3 phase electricity meter Figure 3 – Poly phase electricity allows adjustment of up reference design main board meter reference design to 128 clocks at a time. Thus a meter may be left without mains power for months at a time Freescale has long been focussed on industrial communications and without risk of being reconnected and control, so the evolution to support smart using electricity at the wrong metering builds on existing expertise. tariff rates. Freescale has a number of 8 and 32 bit An interesting by-product of the battery MCU products specifically targeted backed up time of day, is an option to at smart metering, plus a number of use SRAM in the real time clock module reference designs with full documentation for backing up critical data used by the available for customer download. executable code. Data can be accessed at Smart metering is about a complete any time and will be erased should the solution. Accurate measurement must battery be removed at any time, providing be supported by a range of security and a further layer of security. communications features to provide Finally, a range of communications for all options during the 15 plus years peripherals supporting UART, SPI and IIC of deployment. Upgradable firmware are provided to support automated meter in the field and consistent temperature reading (AMR) for the utility provider, compensated real time clocks are very and also make meter data available to much part of a comprehensive solution the consumer for energy management for smart meters. of the home or building. For in-building References: communications, the ZigBee protocol is increasingly popular, as it provides a  Freescale poly-phase meter reference design Smart Energy profile for sharing energy www.freescale.com/webapp/sps/site/prod_ use with other applications, such as summary.jsp?code=RDMCF51EM n remote energy monitors. Interface with ZigBee communications is normally made via UART, which is readily
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HOME AUTOMATION & SMART METERING
Smart home require
Source: Aleksejs Polakovs, Technical Support Team, Farnell
For the last decade, the philosophy of “home automation systems” or “smart home systems” has changed dramatically. From 1998 – 2002 home automation was visualized as a centralized system, where a single computer monitored and controlled all home utilities and appliances. Each device or sensor would be wired to this main computer. This system would feature several different applications, which worked separately, such as; • Smart house lightening • Air conditioner, fridge and freezer • Home alarm/guard system • Phone and fax communication • Multi room audio/video system But these systems have proved to be expensive and not easy to install. Over the last 3 years there have been several great technical implementations, which has led to a transformation of this philosophy: • Bluetooth low energy wireless technology – a recentlyreleased version of the Bluetooth wireless technology aimed at new applications for wireless devices. This Bluetooth specification enables the support of a wide range of applications and smaller form factor devices by offering very low battery usage. • Mobile broadband 3G/3.5G – 3.5G, 3G+ or turbo 3G allows networks are based on UMTS and feature higher data transfer speeds and capacity. Current HSDPA deployments support down-link speeds of 1.8, 3.6, 7.2 and 14.0Mbit/s. Further speed increases are available with HSPA+, which provides speeds of up to 42Mbit/s. • Flash memory – no power is needed to maintain the information stored in the chip. In addition, flash memory offers fast read access times and better kinetic shock resistance. • Social networks such as Twitter – a free social networking and microblogging service that enables its users to send and read 140 character messages known as tweets.
There are three main elements which need further development: • a universal data transfer protocol which is encapsulated in the Bluetooth core data stream to secure transmitted logged data. This protocol should also give the option to communicate with Bluetooth devices directly without a central PC. • a simple programming language for the setting up of equipment. Examples of this are a string command to be sent from a Telnet session and its pictogram analog to be set up through a graphics interface via PC. • server-based WEB resources accessible through a PC or mobile phone. The table below shows a possible graphics realization of a “home automation” WEB page and possible “tweet” examples: Flat temperature set up between 18 and 21° Celsius and to send alarm onto remote WEB while temperature below 10° Celsius and above 25°. > Set temp1 > min == +18 > max == +21 > alarm ON1 == +10 > alarm ON1 == send remote > alarm ON2 == +25 > alarm ON2 == send remote
Entrance alarm set up to send the status onto remote WEB > Set door1 > alarm ON3 == open > alarm ON3 == send remote WEB cam event set up, 10 shots to send onto remote WEB > alarm ON3 == WEBCAM1 > WEBCAM1 == 10 shots > WEBCAM1 == send remote
A possible example of a log file on Twitter: temperature is 19° Celsius and the entrance door was opened at 16:44 Receiving log on 18:05:10:02:10
A new approach These new technologies have enabled home automation systems to have a new structure:
Temp1 == 19
Different types of sensors/data loggers feature built-in microcontrollers, flash memory and Bluetooth transmitters. These devices can be set-up locally or remotely. The data log file is stored in local flash memory and can be read locally using PDA or a mobile phone. Data can also be sent to a PC through an Internet gateway, or even tweeted to a social network.
Of course, these communication sessions must be protected from unauthorized sessions. If there is no internet access, then users can download “reports” from each sensor/data logger locally or from a central PC.
Users will also be able to interact remotely with the network to set up home appliances, such as lighting, an alarm system or heating.
Door 1 == alarm ON3 on 16:44:09:02:10
Most of this hardware is obtainable now; all users need is WEB developers or an electronics components manufacturer to agree to a universal protocol, and to offer WEB and WAPbased applications. n
HOME AUTOMATION & SMART METERING
Automating the home By Jimmy Yeung, Premier Farnell Global Technical Centre
Homes are now expected to serve as a dynamic environment that responds to the resident’s needs and lifestyle. People want their homes to become more comfortable, safer, and efficient as well as boast more life enhancing features. The increase in availability of cheap, and function filled electronics have now enabled these home automation systems to become popular throughout the world. The objective of home automation has evolved from the simple controlling of individual systems such as HVAC, security, lighting, and entertainment to the creation of an enjoyable, energy-saving environment. Home automation system will still control these systems, but will also work to optimize the resident’s environment. This technology is growing in acceptance and expanding from the confines of luxury homes into the mainstream market, as costs fall and more advanced technology is being developed. The improvement of wireless and Power Line Carrier (PLC) technology has also helped home automation to become more practical by replacing the need for every system to be hard wired individually to the control unit. Home owners are now increasingly looking for an end solution that will allow them to consolidate and coordinate all home automation activities into a single system. With the growing acceptance and awareness of open protocols, users can built customized home automation systems step by step, and select their devices or systems from different manufacturers. Home automation products are also opening up a new mainstream consumer market and creating new opportunities for broadband and telephone service providers. Some examples of these products already available on the market are: • • • •
Wireless USB Dongle Wireless Home Automation Coordinator Wireless Home Automation Commander Wireless TCP/IP Gateway
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• Light, Humidity & Temperature Sensors • Smoke Detectors Some add-on home automation management software allows homeowners to monitor and control their Home Control System from any computer or mobile device embedded with a web browser. These options are customizable, and offer users the ability to tailor applications to suit their own homes. Of course, smart meters for power, gas, and water are some of the most important parts of a home automation system. Government and utilities need the smart meters to be able to read meters remotely and, at some point in the future, actually regulate the amount of energy a home can use, or vary utility costs depending on demand from the grid. This would serve as a compelling way to increase demand for home automation systems in new homes. In fact, smart meters really have the potential to be the key that unlocks wider implementation of home automation systems, with networking infrastructures becoming more mature. At the moment ZigBee and Z-Wave are the two new breed of standards-based wireless technologies that promise a bright future for connecting smart metering and home automation devices to the broadband network. ZigBee has a higher bandwidth and more functionality while Z-wave’s development has a giant backer, Intel, supporting. It will be interesting to see which one of these standards will become the eventual winner, or if another contender emerges. n
advertorial 1. Atmel Microcontrollers - offer a complete solution covering the whole 8 to 32bit market and the key requirements of the Smart Grid:The AVR® XMEGA™ delivers 16-bit performance and leading low-power features at an 8-bit price point. With a Peripheral DMA controller, an innovative Peripheral Event System, and a cryptography engine, the AVR XMEGA pushes the boundaries for high-performance 8/16-bit MCUs. For metrology there is both a 12bit DAC and 12bit High Speed ADC that can run at 2Msps, with differential channels and a programmable gain stage giving up to 64X. There is a sleep mode of only 500nA current with the RTC running, ideal for battery operated meters.
Atmel is a market leading ARM MCU and MPU supplier with its AT91SAM family. The AT91SAM Flash MCUs are based on the ARM7TDMI®, Cortex™-M3 and ARM926EJ™ processors, and start with Flash memory densities of 16k Bytes going up to 512k Bytes. Atmel is rapidly expanding the SAM3 CortexM3-based family. The newly introduced
The Smart Meter market is now driven by legislation and regulations due to environmental concerns and necessary energy savings. Smart meters are predisposed to become the gateway into the consumer’s home enabling remote measurement and control of energy consumption. This advance in complexity means a higher performance and functionality is required of the semiconductors that are used to implement the Smart Meter. Atmel is well placed to provide the semiconductor building blocks for computation, wireless communications, memory and security that are essential components.
2. 802.15.4 RF Zigbee for Smart Energy
SAM3S is especially suitable for Smart Meters and can lend itself to single chip solutions looking after metrology, applications and communications. SAM3S key features include:
3. Cryptographic Security solutions
• Cortex-M3 running up to 64MHz
4. Serial DataFlash® and E²PROM
• Full family from 32kB to 512kB, 48pins to 100 pins
Atmel supplies key building blocks for Smart Meter: 1. 8bit and 32bit microcontrollers
Memory Protection Unit improves code protection and secures multi- application/ task execution, metrology can be isolated
• 12-bit 1Msps ADC, with up to 16 channels including differential inputs and integrated gain stage • 0.6uA RTC with calendar feature, 2uA low power mode enabling “Read without Power” • Operating voltage down to 1.62V
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advertorial The high performance and peripheral mix make the SAM9 (ARM9) family well suited for Smart Grid applications such as Data Concentrators and Communication Gateways. Here the total amount of software usually exceeds Mbytes and performance needs 100MIPs - making an Atmel ARM9™ MPU the obvious choice. Peripherals include high speed USB device and host, Ethernet (including a dual option), also several family members have integrated LCD Graphics driver making these devices an excellent fit for In House Display Units.
2. Atmel 802.15.4 RF Zigbee for Smart Energy - we offer complete IEEE 802.15.4-compliant, ZigBee® certified wireless solutions based on family of RF transceivers, AVR and ARM® microcontrollers. There are free software stacks, reference designs, wireless modules and development kits, addressing the needs of Smart Metering. Atmel has low-power IEEE 802.15.4-compliant transceivers for the regional 700/800/900MHz frequency bands available in China, Europe and North America, and the 2.4GHz band available world wide, see table above: The mega128RFA1 is the leading device in our new single-chip megaRF family. It combines the leading AVR microcontroller and our best-in-class 2.4GHz RF transceiver. The combination of low current consumption in all operating modes, a degradation-free supply voltage range down to 1.8V and fast wake-up time from SLEEP mode to active modes make the ATmega128RFA1 very suitable for the Smart Metering market. To run on these devices Atmel has the relevant software stacks and tools. ZigBee is the leading wireless network standard for use in applications such as energy and home automation, To address the specific need of smart metering applications, ZigBee Smart Energy application profile offers utility companies and their suppliers a secure, proven and easy-to-use technology for wireless Home Area Networks (HANs) which connect in-premise devices, such as Smart Meters, thermostats and smart appliances to each other and to wide area energy distribution and control networks. ZigBee Smart Energy enables utility companies and individual homeowners to manage and measure energy usage, control residential peak demand and reduce overall environmental impact. Atmel BitCloud® Profile Suite is a software framework for rapid development of ZigBee Smart Energy devices built around Atmel’s microcontrollers and RF transceivers. It provides the underlying security and protocol stacks to ensure full interoperability and seamless communication across the HAN and comes with a complete reference implementation for ZigBee Smart Energy
device types, including Smart Meters. System designers benefit from Atmel’s ready-to-use, production quality embedded software, code samples and comprehensive documentation. BitCloud Profile Suite is available for megaRF, XMEGA and SAM ARM microcontrollers and transceivers operating in both 2.4GHz and sub-GHz frequency bands, enabling energy management networks to communicate in a variety of adverse environments.
adopted as the preferred non-volatile memory for applications requiring both code and data storage without compromise. The AT45DBxxxD devices, available in densities from 1Mbit through to 64Mbit, employ the signature small page erase architecture, with single or dual independent SRAM buffers for flexibility, while adding a host of new features and considerably upon performance to address a greater range of applications.
3. Atmel Cryptographic Security Solutions – every security problem
These features make the DataFlash the ideal memory choice for metering applications integrating code shadowing and data storage in the same memory device.
simplifies to that of authentication and encryption. With authenticity, is something what it appears to be? Whilst encryption limits access to privileged information only to parties with knowledge of a secret key by scrambling the information. Well designed systems remain secure as long as underlying secret keys remain secret. Secure hardware provides the best protection for secret keys by virtue of tamper monitors, active shields, and encrypted memories. All of Atmel Crypto Products are built from such physically secure hardware.
With Smart Meters (the nodes) there is a huge security risk. Such an embedded network requires a standard interface for communication, with nodes providing data in the same format. The vulnerability is that breaking into one node of the system and extracting the keys would provide the hacker the means to communicate with the other nodes. Managing Keys inside each node becomes the basis to securing the system. Such keys should never be saved in standard unsecured memory devices. Keys should be changed often to prevent those older then a few seconds from being used for communication. Nodes should be authenticated before participating on the network. To accomplish this key management strategy, an Atmel Cryptographic Security IC should be incorporated into each Smart Meter (and the other nodes) on the network. The Atmel AT88SA102S is a member of the CryptoAuthentication family of cost-effective authentication devices designed to securely authenticate an item to which it is attached. It can also be used to exchange session keys so that the system MCU can securely encrypt/ decrypt data. Each CryptoAuthentication device contains a pre-programmed 48 bit serial number, guaranteed to be unique. In addition, it is the first small standard product to implement the SHA-256 hash algorithm, and the 256 bit key renders any exhaustive attacks impossible.
4. Atmel DataFlash® - The page
erase serial DataFlash® family leads the industry in versatility, functionality, and flexibility. DataFlash has quickly been
Metering Applications require memory devices capable of high performance in a multitude of different roles. DataFlash® provides this solution through a range of features including: Granular erase sizes as small as 256 bytes efficiently facilitates E²PROM emulation, data storage and data logging. High speed operation up to 66MHz enables fast code shadowing and data transfer. The device is accessed via a command rich interface that minimizes the software footprint and CPU overhead. Enhanced hardware security features such as flexible sector protection and sector lockdown (make any sector OTP) to ensure critical code or consumption data is not compromised or lost rendering the application un-usable or at risk. Finally, DataFlash devices contain a totally unique embedded 64 Byte factory programmed, plus additional 64 Byte user programmable, Electronic Serial Number (ESN), that can be used to prevent system cloning or tampering. All of these features combine in the smallest 8pin SOIC, and DFN packages to provide an enormous contribution to the over all total system solution and cost by, enhancing performance, system stability and effectiveness whilst reducing the system overhead, minimizing software size in memory and enabling the application to run at much lower power. n
Enable smart energy
in your next design
There is no question that worldwide energy demand will continue to grow, so it becomes ever more important to carefully measure energy usage to ensure that waste is reduced and demand can be safely met. Many regions of the world still remain largely unmetered in contrast to most of the developed nations. Design engineers therefore face many challenges in their quest to create embedded solutions to meet these dynamically changing requirements across a varied and fast changing range of infrastructures.
Smart Meters and Smart Grids are likely to look significantly different from country to country, due to energy availability, financial, political and legislative constraints. Smart Meters In order for the emerging smart grid to provide real-time energy pricing to consumers, smart meters with the ability to accurately measure real-time energy usage will need to be implemented. Highly refined Analog Front Ends (AFEs), specifically designed for smart meters, will be necessary in these systems. Microchip has developed the MCP3901 for both single and three-phase electricity meter systems. The MCP3901 AFE features highaccuracy dual 16-/24-bit Delta-Sigma ADCs with up to 91 dB Signal-to-Noise and Distortion (SINAD), an internal Programmable Gain Amplifier (PGA) and voltage reference, phase-delay compensation, and a modulator output block enabling highly precise measurements. With its unique feature set, high-speed sample rates up to 64ksample/s DESIGN WITH THE BEST at www.farnell.com
and SPI interface, this AFE is ideal for a variety of single and multi-phase metering applications. Integrated PGAs and a low-drift voltage reference enhance the MCP3901 AFEâ€™s ability to measure signals at very small levels, and reduce the amount of external components needed. This enables smaller overall designs at lower costs. The phase-delay compensation block enables the MCP3901 to compensate for differences in phase for three-phase energymetering applications, while the SPI interface provides a simple connection to a microcontroller, and provides engineers more flexibility with their design. Through the SPI interface, engineers can adjust the ADC oversampling ratio to control the resolution and sample rate as dictated by the needs of the application. Home Area Networks ( HAN ) For the new Smart Grid and Smart Meters to communicate and control the loads within a household, advanced communication networks need to be established from the smart meters to the loads, thermostats and to in-home energy monitoring displays. Both wired and wireless protocols are being implemented today, including many IEEE 802.15.4 ZigBee based wireless networks.
EMBEDDED CORNER Microchip’s ZigBee offering is transceiver-based; each ZigBee node consists of a PIC microcontroller and the MRF24J40 2.4GHz IEEE transceiver. In most instances, the PIC microcontroller will be controlling both the ZigBee transceiver and running the energy- related application. These products provide a flexible, cost-effective platform for engineers to create the optimum wireless products and solutions for the given application. The microcontroller can be tailored and optimized to meet the requirements for the entire system, rather than being forced into a single microcontroller that may not meet the entire requirements of the system. As an example, consider an in-home energy monitoring display. This will typically be a battery-powered unit comprised of an LCD display with several push button switches. By using a low power PIC18F87J93 microcontroller and a MRF24J40, designers can create a system that controls the LCD, offers mTouch capacitive sensing capability and controls the ZigBee. Note that implementing a ZigBee network is more than just the hardware; it also requires specialized software to meet the standards set by the ZigBee Alliance. Microchip offers many certified 802.15.4 software stacks, including ZigBee PRO and Smart Energy Profile. To simplify the design and approval of Microchip ZigBee-based wireless products, Microchip provides development support utilizing a certified 2.4 GHz IEEE 802.15.4 radio transceiver module – MRF24J40MA or MB.
Smart Grids Ultimately, the Home Area Network (HAN) has to communicate to the Utility/ Energy provider. Smart Grids offer a raft of benefits to both the Utilities and customers, including demand / response solutions when energy shortages are imminent, real-time meter reading and variable energy tariffs. As with the HAN, various communications protocols are being used or considered. Microchip’s offering centers
around Ethernet connectivity; for Wireless Ethernet, Microchip has the low power 820.11b ZG2100M embedded Wi-Fi module, offering 1&2Mbit/s data rates. All RF components, the baseband and the entirety of the 802.11 MAC reside on-module, creating a simple and cost-effective means to add Wi-Fi connectivity to the embedded system. The ZG2100M connects to its host MCU via SPI and requires low resources from its host processor, enabling a wide range of PIC microcontrollers to be considered. The ZG2100 Wi-Fi driver is integrated within Microchip’s free of charge TCP/IP networking stack. There’s no need to download a separate driver for Wi-Fi or software development. The ZG2100M module is shipped with certification from FCC, ETSI, Japan and Canadian regulatory bodies across a variety of antenna configurations. As with Microchip’s ZigBee solution, there are a range of development tools to accelerate the design cycle. For wired Ethernet, Microchip now offers 8-bit and 32-bit PIC MCUs with integrated Ethernet connectivity. In addition, two standalone Ethernet controllers, ENC28J60 & ENC624J600 provide Ethernet connectivity to PIC microcontrollers running the free Microchip TCP/IP software stack. Users wishing to evaluate Ethernet connectivity and ZigBee connectivity may do so by loading Microchip’s Explorer 16 development platform (DM240011) with the respective PICtail daughter boards. Summary Microchip offers a comprehensive range of ‘building blocks’ for Smart Meters, Smart Grids and Home Area Network. These range from industry-leading Analog Front Ends, low power microcontrollers through to wired and wireless connectivity solutions. n
Helping the electronics industry flourish By Aakriti Kaushik, PR Manager, Premier Farnell
In the EU, for example, SMEs comprise approximately 99% of all firms and employ about 65 million people. In many sectors, SMEs are also responsible for driving innovation and competition and globally account for 99% of business numbers and 40 to 50% of GDP. In January, element14 sponsored an important piece of research, along with the Electronics Leadership Council (ELC) and the UK Electronics Alliance (UKEA), targeting SMEs working at the forefront of British industry, which led to significant revelations. Although the survey was conducted with UK businesses, because of the prevalence of SMEs throughout the world, we believe that the outcome of the survey is relevant to electronics engineers in SMEs everywhere and wish to share the results with you. The main reason for conducting the research was to understand what support and help SMEs need: their challenges and how both government and the trade associations can most usefully invest to provide the maximum benefit for the business leaders of medium-sized enterprises. Inputs were collected from electronics enterprises in the UK, over 70% of which were micro-enterprises, with less than 10 employees. The crossindustry research team also conducted detailed interviews with SME executives and business owners, think tank organizations, trade associations and university research groups. The feedback from the survey and the interviews was overwhelmingly positive that this was the right time to address key issues. Many participants fed back that the consultation process had stimulated them to consider issues which they had previously sidelined! The survey revealed some significant challenges faced by these businesses that are proving to be a hindrance to their success. One of the biggest concerns highlighted was the regulatory burden. In a sector for which innovation is a cornerstone of success, the complexity and difficulty of understanding the nature of
Gauging the confidence levels of Enterprises (SMEs) post recession is extremely important, as this is a sub-sector of highest profitability. In most economies, smaller enterprises are much greater in number.
regulations like RoHS, WEEE and REACH were seen as resource sapping and a key challenge. Other key issues highlighted in the extensive survey included need for greater support to innovation and lack of access to overseas markets. Some respondents also flagged challenges relating to access to finance, cash flow and an increasing skills gap.
with the growing amount of legislation impacting the industry. This is reflected by the companyâ€™s established Global Legislation website (www.global-legislation.com) that provides a wealth of information, including a range of easy to follow guides. The new dedicated SME element14 portal will complement and strengthen the degree of support and information provided by Premier Farnell to SMEs in this area.
To champion the cause of SMEs, element14 will strive to ultimately shape, support and influence regulation and legislation that will make their lives easier, ensure their views are well understood by government as decisions are made, attract funding for SMEs and develop targeted programs that make a real contribution.
The results of this survey and the level and nature of the responses clearly recognized the challenges faced by UK SMEs, and indeed SMEs throughout the world, and indicated that these need to be addressed urgently.
To achieve this, the innovative and successful element14 technology e-community has launched a dedicated â€œSmall Enterprise Resource Centreâ€? a first of its kind in the industry that acts as a platform for discussion and knowledge sharing and contains training modules in the form of podcasts by industry experts. This is boosted by round-the-clock technical support and relevant careers information. element14 also invites group discussions and reflections on the online portal to further drill deeper into Other, please specify the challenges highlighted. It is worth mentioning that Premier Farnell has long recognized the considerable burden placed on the electronics sector business in understanding and complying
For a full copy of the survey findings, to download any of the resources, or to discuss challenges faced by SMEs please visit: http://www.element-14.com/serc n
We are finding it difficult to recruit people with the right skills
We try to recruit people who already have the skills we need
We train people on an ad hoc need basis
Keeping training and skills at the highest level is a great competitive advantage
DESIGN WITH THE BEST at www.farnell.com
The success of small businesses in the electronics sector is crucial to global economies, which is why this dedicated program has been initiated. element14 acts as the perfect tool to provide resource, support and a forum for discussion and information sharing to achieve this objective.
This chart shows that SMEs value training and skills refreshment as a competitive advantage.
Take a Modular Approach to Wireless Connectivity within the Home
Digital Signal Controllers Analog Serial EEPROMs
PICtailTM/PICtail + Daughter Board
This is a demonstration board for evaulating WiFi connectivity using PIC MCUs and the ZeroG 2100 module.
Simplicity – Connection to PIC® MCU via 4 wire SPI – Certified – FCC / IC / ETSI – Software Stack – Free of charge download – Comprehensive range of Development Tools Applications – Security Systems – Heating / Air Conditioning – Entertainment – Lighting
Embedded WiFi – ZG2100 & ZG2101 Modules – Compatible with Microchip’s 8/16/32 bit MCUs – Low Power Consumption – Low System overhead
ZigBee® and MiWiTM MRF24J40MA & MRF24J40MB
– Compatible with Microchip’s 8/16/32 bit MCUs – Common hardware platform supports ZigBee and Microchip’s proprietary MiWi / MiWi P2P protocols
Intelligent Electronics start with Microchip www.microchip.com The Microchip name and logo, the Microchip logo, PIC, PICtail and ZigBee are registered trademarks and MiWi is a trademark of Microchip Technology Incorporated in the U.S.A. and other countries. All other trademarks mentioned herein are property of their respective companies. © 2010, Microchip Technology Incorporated. All Rights Reserved. ME246Eng/03.10Far
Microchip’s growing range of certified RF modules offer an easy way of adding wireless connectivity to embedded applications.
The inside track on
Home Automation & Smart 40 Metering technologies & suppliers
Microchip AR1000 Series Resistive Touch Screen Controller Microchip’s mTouch AR1000 series resistive touch screen controller has sophisticated proprietary touch screen decoding algorithms, allowing it to send applications fully processed and reliable touch coordinates. Cypress PSoC 3 CY8CKIT Cypress’s PSoC 3 CY8CKIT programmable system-on-chip features a 736 segment LCD drive, configurable LCD pin selection and the abilities to drive a 5V display on 0.5V of input and multiple displays. Atmel ZigBit Balanced Output Wireless Modules Atmel’s ZigBit wireless modules are compact 802.15.4/ZigBee modules that feature a complete FCC/CE/ARIB certified RF design IEEE 802.15.4 and ZigBee PRO-certified software.
We hope this publication has helped to make you aware of some of the new solutions for automation and metering that can be incorporated into your next design. Below is a sample of some of the exciting products that have been added to stock recently at Premier Farnell distributers.
NXP LPC13xx 32-bit ARM CortexM3 Microcontrollers NXP’s LPC13xx devices are ARM Cortex-M3-based microcontrollers for embedded applications, featuring a high level of integration and low power consumption. The LPC13xx devices operate at up to 72Mhz.
STMicroelectronics STM8L101EVAL Evaluation Board ST’s STM8L101-EVAL motherboard and daughterboard are a complete development platform for STMicroelectronic’s STM8L101 microcontroller with comparator, I2C, SPI, USART and SWIM debugging support. STMicroelectronics STM32F ARM Cortex-M3 32-bit MCUs STMicroelectronics’ STM32F series of 32-bit Flash microcontrollers is based on the ARM Cortex-M3 core. STM32F microcontrollers are perfectly balanced for applications that do not require extreme low power. Texas Instruments Digital PWM Controller TI’s UCD9220 multi-rail, multi-phase synchronous buck digital PWM controller is for non-isolated DC/DC applications. This device integrates dedicated circuitry for DC/DC loop management with flash memory and a serial interface.
DESIGN WITH THE BEST at www.farnell.com
Analog Devices ADZS-BF518F Blackfin Evaluation Board Analog Devices’ Blackfin ADZSBF518F-EZBRD evaluation board provides developers with a low-cost platform for initial evaluation of the ADSP-BF512/F, BF514/F, BF516/F, BF518/F Blackfin processors via an external JTAG emulator or standalone debug agent board. STMicroelectronics STM8SDiscovery Board ST’s STM8S-Discovery Board is a low cost, quickstart evaluation board with embedded debugger. The board is based on an STM8S105 and includes an ST-LINK and a touch sensing button. Analog Devices ADSPBF527KBCZ-5C2/6C2 DSPs Analog Devices’ ADSP-BF527KBCZ5C2/6C2 DSPs feature a high performance 16-bit/32-bit Blackfin embedded processor core, flexible cache architecture, enhanced DMA subsystem and dynamic power management. Atmel AT32UC3A3 SoC Microcontroller Atmel’s AT32UC3A3 is a complete SoC microcontroller based on the AVR32 UC RISC processor running at up to 66MHz. AVR32 UC is a 32-bit RISC core, designed for cost-sensitive embedded applications, with emphasis on low power consumption. TI ADS1113, ADS1114, and ADS1115 Precision ADCs TI’s ADS1113, ADS1114, and ADS1115 are ADCs with 16 bits resolution, designed with precision, power, and ease of implementation in mind. The ADS1113/4/5 feature an onboard reference and oscillator. Microchip PICkit 3-XLP bundle The PICKit 3-XLP Debug Express 3 with the PIC18F46J50 FS USB Demo Board, XLP PIC samples and a CD including a C compiler, applications notes and training videos is all that is required to evaluate the new NanoWatt XLP Technology. Seoul Semiconductor Acriche Series Power LED Seoul Semiconductor’s Acriche series is designed for AC source operation and high flux output applications. Acriche’s thermal management incorporates state- ofthe-art SMD design and thermal emission material.n
Low profile AC/DC Power Modules TMP Series with extended power from 7 to 30 Watt
• 40 Models offer single, dual, and triple output voltages • UL 508 (15 to 30 Watt models) and UL 60950-1 safety approvals
• Fully encapsulated plastic casing • Available for PCB mount or chassis mount with screw terminals
• • • • • •
Optional DIN-rail mount adaptor Universal Input 85-264 VAC, 47-440 Hz Output voltages from 5 VDC up 48 VDC Protection Class II, double insulation Short circuit protection and overload protection EMC compliance for commercial, residential and industrial applications
• 3 years warranty
The world of technology is changing at an ever more rapid rate—so fast that it is even hard to find solutions/ answers on the internet. At Premier Farnell, we are completely immersed in technology, speaking to over a million customers and thousands of suppliers each week. Our technical support centers are located around the globe and respond to customer questions by phone and by email.
Get Tech is your chance to get advice on any technical query you may have. We will answer all questions and publish the most interesting in the next issue of Technology First.
Q. I require a LED and photo-diode pair. How can I find two devices at the same wavelength? A. If you are struggling to get two devices at the same wavelength, consider purchasing 2 matched LEDs, but use the second LED as a photodiode. The sensitivity might not be as high as a proper photodiode, but may offer enough sensitivity for your application. Q. What is the difference between NOR and NAND Flash A. NOR offers faster read speed and random access capabilities, but its write and erase functions are slow compared to NAND. NAND offers fast write/erase capabilities and is slower than NOR in the area of read speed. NOR’s fast reading capability makes it suitable for code storage in devices such as PDAs and cell phones, while NAND’s fast write/erase combined with its higher density and a lower cost-per-bit make it the favored technology for file storage in Flash drives, MP3 players, digital cameras and USB drives. Q. I have a few LEDs I wish to connect together in a confined area. Can I just connect them via a suitable series resistor to the mains supply? A. There are three main reasons that this is not common practice. First, the series resistor will have a very large value to drop the surplus mains voltage, so a large power resistor will be needed. The reverse voltage during the reversed bias phase of the cycle could potentially damage the LED (though this can be solved by using a blocking diode). Lastly, if the LED is accessible to touch, then if the LED faults into an open circuit condition, potentially dangerous mains voltage will be present across the LED pins. Q. Do I need a low pass filter before injecting a signal into an ADC? A. This is done to attenuate the Nyquist frequencies from distorting the lower frequency sounds, also called an antialiasing filter. It prevents upper frequency signals aliasing with the lower frequencies you wish to preserve. Q. I am considering using OLED displays. What are their advantages and disadvantages compared with LCD displays? DESIGN WITH THE BEST at www.farnell.com
Below are some of the questions most frequently addressed by our technical teams.
Please feel free to comment on any of these, or send in your own question to email@example.com
A. LCD response times decrease as the liquid within the display cools, and they also require backlighting. OLED displays are faster, do not require any backlighting and have more vivid colors. Their main disadvantage is that they currently have a significantly shorter lifespan. Q. I am using a class D amplifier IC. Checking the output with an oscilloscope, the waveform looks fine until I connect the speaker, and it becomes very distorted. Have I got a faulty IC? A. This is a common fault when no decoupling capacitor is used across the supply rails of the IC. Try including a 0.1uF as close to the IC as possible; this helps smooth the power rail voltage when the IC pulls current Q. What is thermal runaway and how can including an emitter resistor (Re) on a bipolar transistor negate it? A. Semiconductor devices have a NTC (negative temperature coefficient).Temperature increases the conduction of the bipolar transistor, so Ic increases. The increase in Ic causes an increase in the power dissipation, increasing the transistor temperature, usually resulting in catastrophic breakdown.
When an emitter resistor is included, an Ic increase (which is proportional to Ie) causes the voltage to be increased across Re reducing the power dissipation in the transistor.
Q. What is 'Ft' in transistor specifications? A. The Ft or Transition Frequency is the frequency at which a transistor’s gain (as used as part of an amplifier) is equal to 1. Small signals with a frequency beyond this point injected into the base will not have their amplitude increased at the collector of the device. This parameter is important when choosing transistors for R.F applications. n
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