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Editors’ Pick: Adafruit’s Limor Fried on the DIY Electronics Revolution

The proliferation of open-source hardware and software has made do-it-yourself electronics accessible to both professional electrical engineers and newbies. Today we’re just at the start of an exciting DIY revolution that promises innovation, adventure, and new social, creative, and business opportunities. How will you get involved? In this essay, Adafruit founder Limor Fried offers her thoughts on the present and future of open-source technology.

I’m an MIT-trained electrical engineer and founder of Adafruit Industries, an open-source hardware (OSH) company in New York City. Normally, I tell people that we design and manufacture electronic gadgets—mostly kits and parts for students who are learning to become engineers—or project packs for people who didn’t realize that they wanted to get into electronics. But really what we do is teach, and we do that by creating OSH. Every design we make is fully documented and given away for free—to anyone, for any purpose. But we also sell completely assembled designs as products. Most people just buy from the Adafruit store or from one of our many distributors, but there are still thousands who look at what we create as points of origin for their own businesses or products.

Another way to put it: we’re basically like a test kitchen with a restaurant attached to it. We come up with new dishes, write the recipes up for others to follow at home (or in their own restaurants), and also serve up the dishes to those who don’t have all the equipment and ingredients—they just want to chow down. Other aspiring chefs look at our videos and recipes and adapt them for their own kitchens all over the world. And, once in a while, those same cooks turn around and give away one of their techniques or recipes to the community. Not everyone gives back, but that’s OK. Enough people contribute to create a vibrant culture of sharing.cloud

The best part about talking about OSH is how easy it is. So much has happened with OSH in the last few years that it’s not like I need to sell a pipe dream. It’s not some “experimental future” or “speculative fiction” about what could occur. OSH is already happening, so all I have to do to predict its future is to accurately describe what’s going on right now. But first, a brief introduction.

Open-Source 101

Nearly everyone knows about open-source software (OSS). Sure, you may not be a coder, but you’ve used the Internet, which is pretty much fully made of OSS: websites running the ubiquitous Apache webserver software, displaying customized sites written in Ruby or PHP, drawing on pools of data stored in MySQL databases all running on server computers running the open-source Linux operating system.

The fantastic thing about all this free OSS is how it has helped proliferate the Internet, improving the functionality of the web through rapid mutations in code (that’s the free-as-in-speech part) and driving down the cost to commodity levels (that’s the free-as-in-beer part). The commodification of the Internet—that is, the marginal cost of an blog or email account is so low that it’s essentially free—and indeed nearly all computer software and hardware would not be possible without OSS.

OK, so that’s the state of the Internet as of circa 1995. Although the details have evolved, the essence of OSS is the same. But something interesting started happening a few years ago in the hardware world (i.e., atoms instead of bits): stuff started getting both complex and cheap. Suddenly, everything had a microcomputer inside of it, and if you had a microcomputer, you needed data to crunch. The market for sensors—what would normally be shoved into extremely expensive military hardware—started ballooning. (When I was in college, a triple-axis accelerometer motion sensor would cost $60. Now it costs less than $1.) Once low-cost sensors and easily reprogrammable logic chips started flooding the market, online communities of engineering geeks started to take notice. Engineers start using what they had learned at work to build hobby projects. The parts were finally cheap enough. And as a result, they started laying down the groundwork: compilers, simulators, and toolchains. That was the mid-1990s. Soon thereafter, geek artists started taking a look and liked what they saw. They started designing interactive art, building on some of the great electronic art concepts of the 1970s. And finally, non-geeks had a crack at it. Complex electronics and electrical engineering went from something requiring years of differential equations to weekend fun.

While all this was happening, something cool began occurring. Just as code geeks created OSS to help commodify the Internet, solder geeks decided to apply the same principles to the creation of hardware (both mechanical and electronic). They started sharing schematics, CAD files, and layouts on social websites. Today, designers use a variety of sites (e.g., Instructables.com, Thingiverse.com, and LetsMakeRobots.com) and via various social services (e.g., Flickr, Twitter, Facebook, and Google+) to give away inventions and post tutorials and instructions for free.

The Proliferation of OSH

The first response we can have is this: OK. Free and OSS erased the costs of software while also increasing demand (and thus lowering the price) for desktop computers. Then followed laptops (say, OLPC, which runs exclusively OSS) and finally cell phones (e.g., Android). So, we’ll also see OSH reduce costs and simultaneously speed up iterations of new and better devices by separating the IP control (say, patents) from the ability to manufacture.

There’s also another response we can take to the proliferation of OSH. Not only is it making it easier than ever to design and manufacture original products to fit a group’s needs, it’s also providing a broad curriculum to the world. Someone who has the desire to learn how to build and repair electronics will not learn much by taking apart a modern cell phone—everything is too small, poorly documented, and hidden. But with OSH, documentation is an essential part of the process—describing why a certain component is chosen and possible alternatives gives insight. The student is empowered to trace the design from thought-process to mathematical analysis to specifications to fabrication.

OSH Projects

Let’s consider some examples of what is happening in OSH right now. First of all, I’m sure you’ve already heard about 3-D printing from MakerBot. It used to be a technology only available to high-end prototyping houses that could spend the tens of thousands of dollars on both machinery and upkeep. But then about five years ago, a few different groups such as Fab@Home and RepRap decided they wanted create low-cost home versions as well as make the projects OSH. So they gave away all the plans with the hopes that others would build, improve, and proliferate the basic plan of low-cost 3-D printing. Now there are over 100 low-cost 3-D printer design variations available for anyone to make. In addition, a massive community is constantly improving the quality, lowering the price, and simplifying things. It’s possible that within a few years we could see 3-D printers that cost $100 and are built of common hardware store parts.

Another example that has promise is the Global Village Construction Set, which is a “manual” of simple, easy-to-repair construction equipment. Instead of high-cost specialized tools from John Deere or Caterpillar, each of a dozen machines can be fabricated using basic steel welding, electrical wiring, and some basic common components. The hope is not that it would replace the many powered tools already available, but that it would enable people to approach the design of new tools without fear that they had nowhere to start from. That is to say, by being broad and simple, it can encourage specialization when needed, whereas most equipment manufacturers would not be interested in selling something unless they had tens of thousands of customers.

Finally, one of my favorite projects is the Dili Village Telco project. There are no phone lines in the East Timor village. There is a cell network, but it’s expensive and not very useful for making calls within the village. David Rowe, a telephony engineer, designed a sort of “micro cell” so that the Timorese in the village could use regular phones to call each other, basically like a little version of AT&T. Rowe designed the very complex hardware, which not only has to work but also has to work well in the difficult environment of a village without cables or consistent power. What I thought was most interesting about the project is how he was giving  away the years’ worth of work, posting up schematics, DSP code, filters, and more with the hope that some company would come by and rip him off. The best thing that could happen for the project is to have the design mass manufactured because then he could get on with the work of deploying and configuring the network boxes instead of figuring out how to get them made.

The Speed & Power of OSH

Now I’ll share personal example of the speed and power of open-source hardware and software. About a year ago, I was mucking about with trying to design a low-cost, high-efficiency solar battery charger. Solar panels are really annoying to deal with, and although there are lots of off-the-shelf solutions for big solar panels—say, over 50 W—there isn’t a lot available for 5 W or under. I ended up designing what I thought was a pretty clever battery charger that used off-the-shelf parts and then began selling it in the Adafruit store. A few months later, I got an e-mail from a fellow who had designed a solar-powered cell phone charger and liked the design and efficiency. He had a Kickstarter going to sell them, and just wanted me to know that he had taken the design and remixed it. Some people would consider such a scenario a nightmare: I spent months in the sun tweaking the design and some guy just rips it off to make money. But I thought it was great. In fact, nothing would make me happier than to hear that every design I’ve worked on and published was used to create a useful product.

Share Knowledge, Share Success

So, on to the future! One thing that makes me most excited is the proliferation of low-cost cell phones that are easy to program (Android in particular). Once you take a programmable cell phone and connect ultra-low-cost sensors, you’ve got a global sensor network—a very powerful tool that enables anyone to measure and monitor the environment.

More sensors, more things talking. You’ll hear about the “Internet of Things” a lot more in the future. A lot of OSH makers cross-pollinate from hobbyist projects to manufacturer products to other industries. For instance, you’ll see medical devices get smarter. Quickly being able to pull from a library of open-source projects and make a Kickstarter or some other crowd-funded service will lower the entry barrier for many engineers and makers. Sure, there are challenges once you actually get the funding, but it’s never been a better time to work on OSH and get your designs out there. Previously, capital needed to be raised via venture capitalists, loans, or friends and family.

What I like about the future of electronics—and DIY electronics in particular—is that it’s more than just about the physical bits. The OSH movement has a built-in cause: sharing knowledge. If we can all provide a little more value when we make something, we can develop more things by standing on each other’s shoulders and make more engineers who share the same values.

FriedLimor Fried founded Adafruit Industries in 2005. She earned a Bachelor’s in EECS and a Master’s of Engineering from MIT This essay first appeared in CC25 (2011).

Power Monitoring IC for High-Accuracy Power Measurement

Microchip Technology recently expanded its power-monitoring IC portfolio with the addition of the MCP39F511. The highly integrated and accurate single-phase power-monitoring IC is designed for the real-time measurement of AC power. It combines the most popular power calculations with unique advanced features, making it well suited for use in high-performance commercial and industrial products (e.g., lighting systems, smart plugs, power meters, and AC/DC power supplies).

Source: Microchip Technology

Source: Microchip Technology

To address industry requirements for better accuracy across current loads, additional power calculations, and event monitoring of various power conditions, the MCP39F511 power-monitoring IC provides all of the popular standard power calculations combined with advanced features. The import and export of active energy accumulation, four-quadrant reactive energy accumulation, zero-crossing detection and dedicated PWM output have now been integrated on-chip, along with the ability to measure active, reactive and apparent power, RMS current and RMS voltage, line frequency, and power factor.

Allowing for more accurate power measurements, which is critical to higher-performance designs, this new device is capable of just 0.1 % error across a wide 4000:1 dynamic range. Additionally, its 512 bytes of EEPROM allow operating-condition storage. The MCP39F511 also includes two 24-bit delta-sigma ADCs with 94.5 dB of SINAD performance, a 16-bit calculation engine, and a flexible two-wire interface. A low-drift voltage reference, in addition to an internal oscillator, is integrated to reduce implementation costs. This unique combination of features and performance allows designers to add highly accurate power-monitoring functions to their end applications with minimal firmware development, speeding development time.

The MCP39F511 is supported by Microchip’s MCP39F511 Power Monitor Demonstration Board (ADM00667), which costs $150. The MCP39F511 is available now for sampling and volume production, in a 28-lead, 5 × 5 mm QFN package. It costs $1.82 each in 5,000-unit quantities.

Source: Microcchip Technology

4-Mb Asynchronous SRAMs with On-Chip Error-Correcting Code

Cypress Semiconductor Corp. recently started sampling 4-Mb asynchronous SRAMs with Error-Correcting Code (ECC). The on-chip ECC feature of the new SRAMs enables them to provide the highest levels of data reliability, without the need for additional error correction chips—simplifying designs and reducing board space. The devices ensure data reliability in a wide variety of industrial, military, communication, data processing, medical, consumer, and automotive applications.

Source: Cypress

Source: Cypress

Soft errors caused by background radiation can corrupt memory content, resulting in a loss of critical data. A hardware ECC block in Cypress’s new asynchronous SRAM family performs all error correction functions inline, without user intervention, delivering best-in-class Soft Error Rate (SER) performance of less than 0.1 FIT/Mb (one FIT is equivalent to one error per billion hours of device operation). The new devices are pin-compatible with current asynchronous fast and low-power SRAMs, enabling customers to boost system reliability while retaining board layout. The 4-Mb SRAMs also include an optional error indication signal that indicates the correction of single-bit errors.

The Cypress 4-Mb asynchronous SRAMs are available in three options—Fast, MoBL and Fast with PowerSnooze—an additional power-saving Deep Sleep mode that achieves 15 µA (max) deep-sleep current for the 4-Mb SRAM. Each of the options is offered in industry standard ×8 and ×16 configurations. The devices operate at multiple voltages (1.8, 3, and 5 V) over –40°C to 85°C (Industrial) and –40°C to +125°C (Automotive-E) temperature ranges.

The new SRAMs are currently sampling in industrial temperature grade, with production expected in July 2015. These devices will be available in RoHS-compliant 32-pin SOIC, 32-pin TSOP II, 36-pin SOJ, 44-pin SOJ, 44-pin TSOP II and 48-ball VFBGA packages.

Source: Cypress 

New Triple Output High Resolution DC Power Supply

Cal Test Electronics recently introduced the new Global Specialties 1320 Power Supply. The 1320 can provide continual output power of 200 VA through its three output supplies. It features constant current or constant voltage modes with automatic crossover. With resolutions of 10 mV and 1 mA, respectively, you can rely on the superior performance of the 1320. There is protection against over voltage and current producing a safe and reliable instrument.

Source: Global Specialties

Source: Global Specialties

Product Features

  • Two variable supplies: 0–32 V, 0–3 A
  • One fixed supply: 5 V, 3 A
  • For greater output connect in Parallel, Series, or Independent modes
  • For greater output connect multiple units together
  • Separate high-resolution, four-digit displays for voltage and current on variable outputs
  • Individual control of voltage and current for variable outputs
  • CV (constant voltage)/CC (constant current) mode operation with automatic crossover
  • LED indication for CV/CC mode
  • Overload indication LED for fixed output
  • Input voltage selection on rear side (120 VAC/ 240 VAC)

The 1320 is available immediately for $479.00.

Elektor Publishes the Ultimate Intel Edison Manual

Elektor’s latest publication on the Intel Edison is a must have for all those with an active interest in the Internet of Things. The book, Getting Started with the Intel Edison, focuses its attention on the Edison, a tiny computer, the size of a postage stamp, with a  lot of power and built-in wireless communication capabilities. In 128 pages, renowned author Bert van Dam helps readers get up to speed with the Edison by making it accessible and easy to use.  It is not a projects book, but a toolbox and guide that allows you to explore the wonderful world of the Intel Edison.

Source: Elektor

Source: Elektor

This book shows readers how to install the software on the Edison as well as on a Windows PC. The Edison Arduino breakout board is used because it is easy to work with. Linux, Arduino C++ and Python are also used and plenty of examples given as to how the Edison can interface with other software. Covering Wi-Fi and Bluetooth, the book also shows you a trick to program sketches over Wi-Fi. Once you have completed the book, not only will your Edison be up and running with the latest software version, but you will also have sufficient knowledge of both hardware and software to start making your own applications. You will even be able to program the Intel Edison over USB and wirelessly both in Arduino C++ and Python. This book is educational and interesting, and really helps to build your knowledge of all things Intel Edison.

Getting started with the Intel Edison is currently available for $35.

Source: Elektor

60-V LED Driver with Internal 4-A Switch & PWM Generator

Linear Technology’s LT3952 is a current mode step-up DC/DC converter with an internal 60-V, 4-A DMOS power switch. It is specifically designed to drive high power LEDs in multiple configurations. It combines input and output current regulation loops with output voltage regulation to operate as a flexible current/voltage source.  The LT3952’s 3-to-42-V input voltage range makes it ideal for a wide variety of applications, including automotive, industrial, and architectural lighting.Linear 3952

The LT3952 can drive up to 16 350-mA white LEDs from a nominal 12-V input, delivering in excess of 15 W. It incorporates a high side current sense, enabling its use in boost mode, buck mode, buck-boost mode or SEPIC topologies. Internal spread spectrum frequency modulation minimizes EMI concerns. The LT3952 delivers efficiencies of over 94% in the boost topology, eliminating the need for external heat sinking, and internal LED short-circuit protection enables added reliability required in most applications. A frequency adjust pin permits the user to program the switching frequency between 200 kHz and 3 MHz, optimizing efficiency while minimizing external component size and cost. The LT3952 delivers over 90% efficiency while switching at 2 MHz in a tiny solution footprint. The LT3952 provides a very compact high power LED driver solution in a thermally enhanced TSSOP-28E package.

The LT3952 has a gate driver for a PMOS LED disconnect switch, delivering dimming ratios of up to 4,000:1 using an external PWM signal. For less demanding dimming requirements, the CTRL pin can be used to offer a 10:1 analog dimming range and an internal PWM generator can be used for 5:1 dimming. The LT3952’s fixed frequency, current-mode architecture offers stable operation over a wide range of supply and output voltages. Output short-circuit protection and open LED protection enhance system reliability. Other features include frequency synchronization, spread spectrum frequency modulation, programmable VIN undervoltage and overvoltage protection, and an input current limit and monitor.

The LT3952EFE is available in a thermally enhanced 28-lead TSSOP package. Three temperature grades are available, with operation from –40°C to 125°C (junction) for the extended, and industrial grades, and a high temperature grade of –40°C to 150°C. Pricing starts at $3.95 each in 1,000-piece quantities and all versions are available from stock. For more information, visit www.linear.com/product/LT3952

Source: Linear Technology

Registration Opens for 19th Annual Worldwide MASTERs Conference

Microchip Technology Inc., a leading provider of microcontroller, mixed-signal, analog and Flash-IP solutions, today announced that registration is open for its 19th annual Worldwide MASTERs Conference at the JW Marriott Desert Ridge Resort in Phoenix, AZ.  The Main Conference takes place from August 19 to 22, 2015. The Pre-Conference is held on August 17-18, 2015.Microchip video MASTERS

The MASTERs Conference provides design engineers with an annual forum for sharing and exchanging technical information about Microchip’s 8-, 16-, and 32-bit PIC microcontrollers, high-performance analog and interface solutions, dsPIC digital signal controllers, wireless and mTouch sensing solutions, memory products, and MPLAB development systems—including the industry’s only singular IDE to support an entire 8-, 16-, and 32-bit microcontroller portfolio.


There is a broad range of class offerings for 2015, to meet the growing needs of software and hardware design engineers and engineering managers, with more than 100 classes being offered—39 of which are new this year.  In addition to lecture-based classes, there are 47 hands-on workshops that enable attendees to learn more about specific applications by using development tools and writing code in the classrooms.  Classes are available for engineers with advanced experience or little knowledge in the concepts and basics of the technology being discussed.

Based on its overwhelming success at previous MASTERs, Microchip is again offering a two-day Pre-Conference for those who wish to attend as many classes as possible during the week. These classes are also designed for beginner through advanced attendees. For example, “Introduction to Embedded Programming Using C” is a two-day, 16-hour, step-by-step crash course in C, with practical hands-on exercises.

MASTERs classes cover a wide range of electronic-engineering topics, including connectivity sessions on Ethernet, TCP/IP, USB, CAN and wireless (e.g., Bluetooth and Wi-Fi), graphics and capacitive-touch interface development, intelligent power supplies, firmware development, motor control, selecting op amps for sensor applications, DSP and using an RTOS.

Additional activities include networking sessions between third-party partners and attendees to discuss relevant design topics, meeting with third-party development tool experts and a simulated wafer fab plant tour.

Entry to the MASTERs Conference courses, a USB Flash Drive with all class materials, round-trip airport transportation, accommodations for three nights with meals, evening entertainment, and more are included in the Conference cost of $1,526, if you register by May 8, 2015 to receive the Early Bird Discount.

Source: Microchip Technology

 

New XMC4800 Microcontrollers with EtherCAT Technology Support Industry 4.0

Infineon Technologies AG has launched a new XMC4800 series of 32-bit microcontrollers with on-chip Ethernet for Control Automation Technology (EtherCAT) node. With its real-time capability, the XMC4800 series is intended to drive networked industrial automation and Industry 4.0 applications.Infineon XMC4800

The EtherCAT node is integrated on an ARM Cortex-M-based microcontroller with on-chip flash and analog/mixed signal capability. The XMC4800 series comprises at least 18 members varying in memory capacity, temperature range and packaging. All XMC4800 microcontrollers will be AEC Q100 qualified, making them also suited for use in commercial, construction, and agricultural vehicles.

The XMC4800 series is a member of the XMC4000 family, which uses the ARM Cortex-M4 processor and was specifically developed for use in the automation of manufacturing and buildings as well as electric drives and solar inverters. The XMC4800 series offers a seamless upgrade path to EtherCAT technology with pin and code compatibility to the established XMC4000 microcontrollers. The XMC4800 enables the use of EtherCAT under the harsh condition of up to 125°C ambient temperature.

 

With the integration of the EtherCAT functionality, the XMC4800 enables the most compact design without need for a dedicated EtherCAT ASIC, external memory and clock crystal. It offers a 144-MHz-CPU, up to 2 MB of embedded flash memory, 352 KB of RAM and a comprehensive range of peripheral and interface functions. The peripherals include four parallel fast 12-bit A/D converter modules, two 12-bit D/A converters, four delta sigma demodulator modules, six capture/compare units (CCU4 and CCU8), and two positioning interface modules. In addition to its EtherCAT functionality, its communication functions comprise interfaces for Ethernet, USB, and SD/MMC. Also, the XMC4800 series offers six CAN nodes, six serial communication channels, and one external bus interface for communication. The three package options are LQFP-100, LQFP-144, and LFBGA-196.

Samples of the series XMC4800 with EtherCAT technology will be available in August 2015. Volume production is scheduled for Q1 2016.

Source: Infineon 

 

 

Low-Profile PCIe Board Platform

BittWare recently announced today its second low-profile PCIe board—the A5-PCIe-S (A5PS). The new board is based on Altera’s Arria V GZ FPGA, which provides a high level of system integration and flexibility for I/O, routing, and processing. Thus, the A5PS is a reliable platform for a variety of applications (e.g., network processing, security, broadcast, and signals intelligence).BittWare A5PS

Featuring dual SFP+ cages that run up to 12.5 Gbps, the A5PS provides dual 10GigE ports using optical transceivers as well as passive copper cabling up to 7 m. These ports are serviced by the advanced 28-nm Arria V GZ FPGA, which also supports a Gen3 x8 PCIe interface and either 8-GB DDR3 or 36-MB QDRII+. Sophisticated time-stamping and synchronization options are supported by dual SMA connectors for interfacing to 1-PPS or 10-MHz reference clocks, in addition to the tunable on-board high accuracy, temperature compensated oscillator (TCXO). A comprehensive Board Management Controller (BMC) with host software support for advanced system monitoring is also provided.

The A5PS features and specifications include:

  • Altera Arria V GZ FPGA
  • PCIe x8 interface supporting Gen1, Gen2, or Gen3
  • Dual SFP+ cages for 2x 10GigE: Support for a wide range of optical transceiver; built-in low-latency active drivers/receivers for passive copper cables up to 7 m
  • Memory options (pick one): DDR3 (single 72-bit bank of up to 8 GBytes DDR3-1600 with ECC); QDRII+ (two 18-bit banks of up to 144 Mb each—288 Mb or 36 MB total)
  • Board Management Controller for Intelligent Platform Management
  • USB 2.0 for programming, debug, or control
  • Timestamping and synchronization support
    • Dual SMA for reference clock/synchronization inputs
    • Tunable high-accuracy TCXO
    • Programmable clock synthesizer (Si5338)
  • Complete software support with BittWare’s BittWorks II Toolkit
  • Broad range of IP offerings
    • 10 GigE MAC
    • TCP/IP Offload Engines (TOE), UDP Offload Engines
    • PTP/IEEE-1588
    • PCIe DMA

The A5PS board currently costs $1,500 in 1000s for the A5PS with the Arria V GZ E1 with no external memory. Contact BittWare for additional configurations, pricing, and details.

Source: BittWare

 

How to Improve Software Development Predictability

The analytical methods of failure modes effects and criticality analysis (FMECA) and failure modes effects analysis (FMEA) have been around since the 1940s. In recent years, much effort has been spent on bringing hardware related analyses such as FMECA into the realm of software engineering. In “Software FMEA/FMECA,” George Novacek takes a close look at software FMECA (SWFMECA) and its potential for making software development more predictable.

The roots of failure modes effects and criticality analysis (FMECA) and failure modes effects analysis (FMEA) date back to World War II. FMEA is a subset of FMECA in which the criticality assessment has been omitted. Therefore, for simplicity, I’ll be using the terms FMECA and SWFMECA only in this article. FMECA was developed for identification of potential hardware failures and their mitigation to ensure mission success. During the 1950s, FMECA became indispensable for analyses of equipment in critical applications, such as those occurring in military, aerospace, nuclear, medical, automotive, and other industries.

FMECA is a structured, bottom-up approach considering a failure of each and every component, its impact on the system and how to prevent or mitigate such a failure. FMECA is often combined with fault tree analysis (FTA) or event tree analyses (ETA). The FTA differs from the ETA only in that the former is focused on failures as the top event, the latter on some specific events. Those analyses start with an event and then drill down through the system to their root cause.

In recent years, much effort has been spent on bringing hardware related analyses, such as reliability prediction, FTA, and FMECA into the realm of software engineering. Software failure modes and effects analysis (SWFMEA) and software failure modes, effects, and criticality analysis (SWFMECA) are intended to be software analyses analogous to the hardware ones. In this article I’ll cover SWFMECA as it specifically relates to embedded controllers.

Unlike the classic hardware FMECA based on statistically determined failure rates of hardware components, software analyses assume that the software design is never perfect because it contains faults introduced unintentionally by software developers. It is further assumed that in any complicated software there will always be latent faults, regardless of development techniques, languages, and quality procedures used. This is likely true, but can it be quantified?

SOFTWARE ANALYSIS

SWFMECA should consider the likelihood of latent faults in a product and/or system, which may become patent during operational use and cause the product or the system to fail. The goal is to assess severity of the potential faults, their likelihood of occurrence, and the likelihood of their escaping to the customer. SWFMECA should assess the probability of mistakes being made during the development process, including integration, verification and validation (V&V), and the severity of these faults on the resulting failures. SWFMECA is also intended to determine the faults’ criticality by combining fault likelihood with the consequent failure severity. This should help to determine the risk arising from software in a system. SWFMECA should examine the development process and the product behavior in two separate analyses.

First, Development SWFMECA should address the development, testing and V&V process. This requires understanding of the software development process, the V&V techniques and quality control during that process. It should establish what types of faults may occur when using a particular design technique, programming language and the fault coverage of the verification and validation techniques. Second, Product SWFMECA should analyze the design and its implementation and establish the probability of the failure modes. It must also be based on thorough understanding of the processes as well as the product and its use.

In my opinion, SWFMECA is a bit of a misnomer with little resemblance to the hardware FMECA. Speculations what faults might be hidden in every line of code or every activity during software development is hardly realistic. However, there is resemblance with the functional level FMECA. There, system level effects of failures of functions can be established and addressed accordingly. Establishing the probability of those failures is another matter.

The data needed for such considerations are mostly subjective, their sources esoteric and their reliability debatable. The data are developed statistically, based on history, experience and long term fault data collection. Some data may be available from polling numerous industries, but how applicable they are to a specific developer is difficult to determine. Plausible data may perhaps be developed by long established software developers producing a specific type of software (e.g., Windows applications), but development of embedded controllers with their high mix of hardware/software architectures and relatively low-volume production doesn’t seem to fit the mold.

Engineers understand that hardware has limited life and customers have no problem accepting mean time between failures (MTBF) as a reality. But software does not fail due to age or fatigue. It’s all in the workmanship. I have never seen an embedded software specification requiring software to have some minimum probability of faults. Zero seems always implied.

SCORING & ANALYSIS

In the course of SWFMECA preparation, scores for potential faults should be determined: severity, likelihood of occurrence, and potential for escaping to the finished product. The scores between 1 to 10 are multiplied and thus the risk priority number (RPN) is obtained. An RPN larger than 200 should warrant prevention and mitigation planning. Yet the scores are very much subjective—that is, they’re dependent on the software complexity, the people, and other impossible to accurately predict factors. For embedded controllers the determination of the RPN appears to be just an analysis for the sake of analysis.

Statistical analyses are used every day from science to business management. Their usefulness depends on the number of samples and even with an abundance of samples there are no guarantees. SWFMECA can be instrumental for fine-tuning the software development process. In embedded controllers, however, software related failures are addressed by FMECA. SWFMECA alone cannot justify the release of a product.

EMBEDDED SOFTWARE

In embedded controllers, causes of software failures are often hardware related and exact outcomes are difficult to predict. Software faults need to be addressed by testing, code analyses, and, most important, mitigated by the architecture. Redundancy, hardware monitors, and others are time proven methods.

Software begins as an idea expressed in requirements. Design of the system architecture, including hardware/software partitioning is next, followed by software requirements, usually presented as flow charts, state diagrams, pseudo code, and so forth. High and low levels of design follow, until a code is compiled. Integration and testing come next. This is shown in the ubiquitous chart in Figure 1.

Figure 1: Software development "V" model

Figure 1: Software development “V” model

During an embedded controller design, I would not consider performing the RPN calculation, just as I would not try to calculate software reliability. I consider those purely statistical calculations to be of little practical use. However, SWFMECA activity with software ETA and FTA based on functions should be performed as a part of the system FMECA. The software review can be to a large degree automated by tools, such as Software Call Tree and many others. Automation notwithstanding, one should always check the results for plausibility.

TOOLS

Software Call Tree tells us how different modules interface and how a fault or an event would propagate through the system. Similarly, Object Relational Diagram shows how objects’ internal states affect each other. And then there are Control Flow Diagram, Entity Relationship Diagram, Data Flow Diagram, McCabe Logical Path, State Transition Diagram, and others. Those tools are not inexpensive, but they do generate data which make it possible to produce high-quality software. However, it is important to plan all the tests and analyses ahead of the time. It is easy to get mired in so many evaluations that the project’s cost and schedule suffer with little benefit to software quality.

The assumed probability of a software fault becomes a moot point. We should never plunge ahead releasing a code just because we’re satisfied that our statistical development model renders what we think is an acceptable probability of a failure. Instead, we must assume that every function may fail for whatever reason and take steps to ensure those failures are mitigated by the system architecture.

System architecture and software analyses can only be started upon determination that the requirements for the system are sufficiently robust. It is not unusual for a customer to insist on beginning development before signing the specification, which is often full of TBDs (i.e., “to be defined”). This may be leaving so many open issues that the design cannot and should not be started in earnest. Besides, development at such a stage is a violation of certification rules and will likely result in exceeding the budget and the schedule. Unfortunately, customers can’t or don’t always want to understand this and their pressure often prevails.

The ongoing desire to introduce software into the hardware paradigm is understandable. It could bring software development into a fully predictable scientific realm. So far it has been resisting those attempts, remaining to a large degree an art. Whether it can ever become a fully deterministic process, in my view, is doubtful. After all, every creative process is an art. But great strides have been made in development of tools, especially those for analyses, helping to make the process increasingly more predictable.

This article appears in Circuit Cellar 297, April 2015.

The Internet of Things: A Very Disruptive Force

We met with Geoff Lees (Senior Vice President & General Manager of Microcontrollers, Freescale) at the 2015 Embedded World Show in Nuremberg, Germany. We asked him about the Internet of Things, the big changes on the embedded systems horizon, and what it takes to be a successful engineer.L1060979

CIRCUIT CELLAR: The Embedded World Show is one of the biggest that specifically focuses on embedded technologies, new products, and design. What makes this show special?

GEOFF: In Europe we go to the Electronica in Munich and also to this show. At Electronica, we meet up with our clients and distributors. This Embedded show has a much more technical focus. Here we meet with the individual designers and technical teams of our clients and see most in-depth technical discussions. At the Electronica show we talk business; here we talk more technology and what it can do for the client.

CIRCUIT CELLAR: Talking about individual engineers, we remember last year in your press conference you mentioned a focus on hobbyists. That’s quite remarkable for a company like Freescale. We also see there is a small “maker lab” in your booth at the show.

GEOFF: It is important to address makers and hobbyists for two reasons. First, there are the sheer numbers. At Maker Show in New York, you see there a 100,000 people showing up. At a show like this, it is 20,000 to 25,000. Here we see the engineering teams of companies. But what is interesting about the maker community is that individuals can have an idea or innovation, create and build the prototypes, but instead of having a company making this, they have the community and can even go to market.L1060983

CIRCUIT CELLAR: Sometimes we get the idea that the bigger companies are looking at the crowd-funding communities as part of—or as a replacement for—their own R&D activities. How does that work for a company like Freescale?

GEOFF: One thing that’s very clear in today’s world is speed. Sometimes an individual, with very little obstruction, can have speed that cannot be matched by companies—and someone who can respond or react to the requirements almost instantaneously has an advantage. There are so many of these. Finding and communicating with them is almost an impossible task. You really have to watch carefully. It is almost impossible to know where the next innovation is coming from.

CIRCUIT CELLAR: You call the Internet of Things, the Internet of Tomorrow?

GEOFF: The IoT is a very disruptive force. It started out as a buzz, but it is in the “nature” of microcontrollers to connect and to communicate. With new Wi-Fi concepts, low-power and IPv6 the road is clear for many new applications. To demonstrate the new technologies we have a “bigger than big” truck driving through the US. We put it in the parking lot of companies and demo not only our own products, but also their products as well as the solutions of their competitors. With a show you get the designers or marketing people. With the truck we also have CEOs and CTOs for a coffee—the guys who would not even consider visiting our website!

CIRCUIT CELLAR: But how will the IoT affect us?

GEOFF: I currently have eight apps on my phone that are all IoT controls, monitoring my house, solar panels, and vehicle. I expect that number will grow. Also, devices will talk to devices and create new independent controls. “Big Ass Fans” is a nice example of that. That company is making fans but is also playing a role in home automation. Their latest model fan talks to the NEST. Only a small difference in temperature can set the fan to work rather than your air conditioning, either by cooling down or circulating the hotter air downwards.

CIRCUIT CELLAR: Everyone knows that standards are key to making the IoT really happen. What role does Freescale have in this?

GEOFF: We joined up with the Thread Group. This initiative started with only eight companies, and that number has grown to 50 in five months, and now we see around 1,000 companies that look for information. If we see a growth from eight to 50 to 1,000, you know that there is a momentum which will result in new standards. The Thread Group uses existing (IEEE 8082.15.4) technologies and standards to build a new wireless mesh protocol that will enable to overcome the current limitations in wireless home automation. The Thread Networks will aim at the simple installation of new nodes and it can scale up to 250 and more devices in a single network. No company—whether you are Cisco or IBM or Oracle—has the power to set the standard on their own, maybe a part of it, but not all. This will go as usual, an initiative will gain critical mass, and then the momentum drives it through. This will all be about momentum.

The complete interview appears in Circuit Cellar 297 (April 2015).

Toshiba Expands TX04 Range of ARM Cortex-M4F-Based Microcontrollers

Toshiba Electronics Europe has announced a new ARM Cortex-M4F based microcontroller for use in secure systems control. The TMPM46BF10FG expands its existing TX04 range and adds enhanced security features that are well-suited to applications in Internet of Things (IoT) devices, energy management systems, sensor technology, and industrial equipment.Toshiba TMPM46BF10FG

Users of secure communications control systems increasingly require mass memory data for firmware generation management, failure analysis, and high-precision consecutive data storage. The TMPM46BF10FG meets these requirements for high-level security features, such as tamper detection and information concealment. The IC also meets the need to reduce the number of parts on system circuit board by supporting large capacity memory.

Featuring an ARM Cortex-M4F core, with a maximum operating frequency of 120 MHz, the TMPM46BF10FG incorporates 1,024 KB of flash memory and 514-KB SRAM required for secure communications control, four types of security circuits for network communications. The microcontroller also integrates an SLC NAND flash memory controller and 4- and 8-bit error correction circuitry (BCH ECC) that supports memory expansion with 1-to-4-Gb SLC NAND flash memory chips.

To provide additional levels of safety, the IC includes a 16-channel interrupt input and a clock-independent watchdog timer, which operates separately from the system clock, improving the safety of system functions. In the case of a system clock malfunction, the watchdog timer is still capable of detecting errors.

The TMPM46BF10FG incorporates a true random number generator (TRNG: SP800-90C standard) through the combination of a random entropy seed generation (ESG) circuit and Hash-DRGB created by the secure hash processor (SHA) and software program. This meets the robust standards of security that are required in network communications. The hardware based AES encryption/decryption process meets FIPS180-4 and FIPS197 standards and reduces the load on the CPU, in combination with a random seed generation circuit (ESG), and a multiple-length arithmetic (MLA) used to calculate elliptic curves for asymmetric ciphers.

The TMPM46BF10FG features direct memory access (32 channel), a 12-bit AD converter (8 channel), 16-bit timer (8 channel), SPP (3 channel), SIO/UART (4 channel), full UART (2 channel) I2C (3 channel), with an operating voltage of 2.7 to 3.6 V. Housed in an LQFP100 package, the IC measures just 14 mm × 14 mm, with a 0.5-mm pitch.

Samples are now available. Mass production will begin in October.

Source: Toshiba

 

 

RTG4 Radiation-Tolerant FPGAs for High-speed Signal Processing Applications

Microsemi Corp. today announced availability of its RTG4 high-speed, signal-processing radiation-tolerant FPGA family. The RTG4’s reprogrammable flash technology offers complete immunity to radiation-induced configuration upsets in the harshest radiation environments, requiring no configuration scrubbing, unlike SRAM FPGA technology. RTG4 supports space applications requiring up to 150,000 logic elements and up to 300 MHz of system performance.Microsemi RTG4-  3-4view

Typical uses for RTG4 include remote sensing space payloads, such as radar, imaging and spectrometry in civilian, scientific and commercial applications. These applications span across weather forecasting and climate research, land use, astronomy and astrophysics, planetary exploration, and earth sciences. Other applications include mobile satellite services (MSS) communication satellites, as well as high altitude aviation, medical electronics and civilian nuclear power plant control. Such applications have historically used expensive radiation-hardened ASICs, which force development programs to incur substantial cost and schedule risk. RTG4 allows programs to access the ease-of-use and flexibility of FPGAs without sacrificing reliability or performance.

The flexibility, reliability and performance of RTG4 FPGAs make it much easier to achieve this. RTG4 is Microsemi’s latest development in a long history of radiation-tolerant FPGAs that are found in many NASA and international space programs.

Key product features include:

  • Up to 150,000 logic elements; each includes a four-input combinatorial look-up table (LUT4) and a flip-flop with built-in single event upset (SEU) and single event transient (SET) mitigation
  • High system performance, up to 300 MHz
  • 24 serial transceivers, with operation from 1 Gbps to 3.125 Gbps
  • 16 SEU- and SET-protected SpaceWire clock and data recovery circuits
  • 462 SEU- and SET-protected multiply-accumulate mathblocks
  • More than 5 Mb of on-board SEU-protected SRAM
  • Single event latch-up (SEL) and configuration memory upset immunity
  • Total ionizing dose (TID) beyond 100 Krad

Engineering silicon, Libero SoC development software, and RTG4 development kits are available now. RTG4 FPGAs and development kits have already shipped to some of the 120+ customers engaged in the RTG4 lead customer program. Flight units qualified to MIL-STD-883 Class B are expected to be available in early 2016.

Microsemi will present more information on RTG4 FPGAs in a live webinar on May 6 and will also be hosting Microsemi Space Forum events in the U.S., India and Europe starting in June, presenting information on RTG4 FPGAs and the extensive range of Microsemi space products.

Source: Microsemi Corp.

New High-Speed CMOS DDR SDRAMs

Alliance Memory recently announced new high-speed CMOS double data rate synchronous DRAMs (DDR SDRAM) with densities of 256 Mb (AS4C32M8D1), 512 Mb (AS4C64M8D1), and 1 Gb (AS4C64M16D1) in the 60-ball 8-mm × 13-mm × 1.2 mm TFBGA package and the 66-pin TSOP II package with a 0.65-mm pin pitch. The devices provide reliable drop-in, pin-for-pin-compatible replacements for a number of similar solutions in industrial, medical, communications, and telecommunications products requiring high memory bandwidth. They are particularly well-suited to high performance in PC applications.Alliance Memory DDR

The AS4C32M8D1, AS4C64M8D1, and AS4C64M16D1 are internally configured as four banks of 32M word × 8 bits, 64M word × 8 bits, and 64M word × 16 bits, respectively. The DDR SDRAMs offer a synchronous interface. They operate from a single +2.5-V (±0.2 V) power supply, and they are lead (Pb)- and halogen-free.

The AS4C32M8D1, AS4C64M8D1, and AS4C64M16D1 feature fast clock rates of 200 MHz and 166 MHz. They are offered in commercial (0°C to 70°C) and industrial (–40°C to 85°C) temperature ranges. The DDR SDRAMs provide programmable read or write burst lengths of 2, 4, or 8. An automatic pre-charge function provides a self-timed row pre-charge initiated at the end of the burst sequence. Easy-to-use refresh functions include auto- or self-refresh, while a programmable mode register allows the system to choose the most suitable modes to maximize performance.

With the addition of the AS4C32M8D1, AS4C64M8D1, and AS4C64M16D1 to its portfolio, Alliance Memory now offers the most extensive lineup of DDR SDRAMs in the industry, featuring densities of 64 Mb, 128 Mb, 256 Mb, 512 Mb, and 1 Gb. For Alliance Memory’s customers, the devices eliminate costly redesigns by providing long-term support for end-of-life (EOL) components. In addition, the company doesn’t perform die shrinks, which frees up engineering resources.

Samples and production quantities are available with lead times of six to eight weeks for large orders. Pricing for US delivery starts at $1 per piece.

Source: Alliance Memory

Power-Saving Flat Panel VCOM Buffer Amplifier

Exar Corp. recently announced a next-generation VCOM control product based on patent-pending innovative architecture. The iML2911 provides a solution to add two additional power supply voltages readily available in panel electronics. The device employs sensing circuitry for VCOM output load requirement and automatically switches between multiple supply voltage combinations. This results in 50% savings of energy for still images and 25% to 30% savings for dynamic display images without affecting the quality. The iML2911 is also advantageous for use in TV panel applications, where heat dissipation from VCOM buffer devices is a major concern for panel and set makers, as local heating can negatively affect image quality.Exar_iML2911

Summary of features:

  • Significant power savings for managing VCOM voltage level
  • Patent-pending, integrated sensing circuitry
  • Up to 12V VCOM voltage range

The iML2911 is currently available in an eight-pin TDFN package and in a nine-ball CSP. Pricing starts at $0.45 in 10,000-piece quantities. Device samples and evaluation circuit boards are currently available online or from your local sales office.

Source: Exar Corp.