June Circuit Cellar: Sneak Preview

The June issue of Circuit Cellar magazine is coming soon. And we’ve planted a lovely crop of embedded electronics articles for you to enjoy.

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Here’s a sneak preview of June 2018 Circuit Cellar:


PCB Design and Verification
PCB design tools and methods continue to evolve as they race to keep pace with faster, highly integrated electronics. Automated, rules-based chip placement is getting more sophisticated and leveraging AI in interesting ways. And supply chains are linking tighter with PCB design processes. Circuit Cellar Chief Editor Jeff Child looks at the latest PCB design and verification tools and technologies.

PCB Ground Planes
Tricky design decisions crop up when you’re faced with crafting a printed circuit board (PCB) for any complex system—and many of them involve the ground plane. There is dealing with noisy components and deciding between a common ground plane or separate ones—and that’s just the tip of the iceberg. Robert Lacoste shares his insights on the topic, examining the physics, simulation tools and design examples of ground plane implementations.

Product Focus: AC-DC Converters
To their peril, embedded system developers often treat their choice of power supply as an afterthought. But choosing the right AC-DC converter is critical to the ensuring your system delivers power efficiently to all parts of your system. This Product Focus section updates readers on these trends and provides a product album of representative AC-DC converter products.


Sensors and Measurement
While sensors have always played a key role in embedded systems, the exploding Internet of Things (IoT) phenomenon has pushed sensor technology to the forefront. Any IoT implementation depends on an array of sensors that relay input back to the cloud. Circuit Cellar Chief Editor Jeff Child dives into the latest technology trends and product developments in sensors and measurement.

Passive Infrared Sensors
One way to make sure that lights get turned off when you leave a room is to use Passive Infrared (PIR) sensors. Jeff Bachiochi examines the science and technology behind PIR sensors. He then details how to craft effective program code and control electronics to use PIR sensors is a useful way.

Gesture-Recognition in Boxing Glove
Learn how two Boston University graduate students built a gesture-detection wearable that acts as a building block for a larger fitness telemetry system. Using a Linux-based Gumstix Verdex, the wearable couples an inertial measurement unit with a pressure sensor embedded in a boxing glove to recognize the user’s hits and classify them according to predefined, user-recorded gestures.


Internet of Things Security (Part 3)
In this next part of his article series on IoT security, Bob Japenga looks at the security features of a specific series of microprocessors: Microchip’s SAMA5D2. He examines these security features and discusses what protection they provide.

Aeronautical Communication Protocols
Unlike ground networks, where data throughout is the priority, avionics networks are all about reliability. As a result, the communications protocols used in for aircraft networking seem pretty obscure to the average engineer. In this article, George Novacek reviews some of the most common aircraft comms protocols including ARINC 429, ARINC 629 and MIL-STD-1553B


Murphy’s Laws in the DSP World (Part 1)
A Pandora’s box of unexpected issues gets opened the moment you move from the real world of analog signals and enter the world of digital signal processing (DSP). In Part 1 of this new article series, Mike Smith defines six “Murphy’s Laws of DSP” and provides you with methods and techniques to navigate around them.

Processor Design Techniques and Optimizations
As electronics get smaller and more complex day by day, knowing the basic building blocks of processors is more important than ever. In this article, Nishant Mittal explores processor design from various perspectives—including architecture types, pipelining and ALU varieties.

Non-isolated Up Converters Support High-Performance GPUs

Vicor has announced a 12 V to 48 V non-isolated up converter to support 48 V high-performance GPUs in data centers that are still relying on legacy 12 V power distribution. The 2317 NBM converts 12 V to 48 V with over 98% peak efficiency, 750 W continuous and 1 kW peak power in a 23 mm x 17 mm x 7.4mm surface-mount SM-ChiP package. The NBM (NBM2317S14B5415T00) provides a complete solution with no external input filter or bulk capacitors required. By switching at 2 MHz with ZVS and ZCS, the NBM provides low output impedance and Megahertz-fast transient response to dynamic loads. The NBM incorporates hot-swap and inrush current limiting.

The NBM supports state-of-the-art 48 V input GPUs using Power-on-Package (“PoP”) Modular Current Multipliers (“MCMs”) driven from a 48 V node sourcing a small fraction (1/48th) of the GPU current. Current multiplication overcomes the power delivery boundaries imposed by traditional 12 V systems standing in the way of higher bandwidth and connectivity.

The Vicor Power-on-Package modules build upon Factorized Power Architecture (FPA) systems deployed in high-performance computers and large-scale data centers. FPA provides efficient power distribution and direct conversion from 48 V to 1 V for GPUs, CPUs and ASICs demanding up to 1,000 A. By deploying current multiplication in close proximity to high-current Artificial Intelligence (AI) processors, PoP MCMs enable higher performance and system efficiency.

Vicor | www.vicorpower.com


SMARC Module Features Hexa-Core i.MX8 QuadMax

By Eric Brown

iWave has unveiled a rugged, wireless enabled SMARC module with 4 GB LPDDR4 and dual GbE controllers that runs Linux or Android on NXP’s i.MX8 QuadMax SoC with 2x Cortex-A72, 4x -A53, 2x -M4F and 2x GPU cores.

iW-RainboW-G27M (front)

iWave has posted specs for an 82 mm x 50 mm, industrial temperature “iW-RainboW-G27M” SMARC 2.0 module that builds on NXP’s i.MX8 QuadMax system-on-chip. The i.MX8 QuadMax was announced in Oct. 2016 as the higher end model of an automotive focused i.MX8 Quad family.

Although the lower-end, quad-core, Cortex-A53 i.MX8M SoC was not fully announced until after the hexa-core Quad, we’ve seen far more embedded boards based on the
i.MX8M , including a recent Seco SM-C12

iW-RainboW-G27M (back)

SMARC module. The only other i.MX8 Quad based product we’ve seen is Toradex’s QuadMax driven Apalis iMX8 module. The Apalis iMX8 was announced a year ago, but is still listed as “coming soon.”



i.MX8 Quad block diagram (dashed lines indicate model-specific features) (click image to enlarge)


Like Rockchip’s RK3399, NXP’s i.MX8 QuadMax features dual high-end Cortex-A72 cores and four Cortex-A53 cores. NXP also offers a similar i.MX8 QuadPlus design with only one Cortex-A72 core.

The QuadMax clock rates are lower than on the RK3399, which clocks to 1.8 GHz (A72) and 1.2 GHz (A53). Toradex says the Apalis iMX8’s -A72 and -A53 cores will clock to 1.6 GHz and 1.2 GHz, respectively.

Close-up of i.MX8 QuadMax on iW-RainboW-G27M

Whereas the i.MX8M has one 266 MHz Cortex-M4F microcontroller, the Quad SoCs have two. A HIFI4 DSP is also onboard, along with a dual-core Vivante GC7000LiteXS/VX GPU, which is alternately referred to as being two GPUs in one or having a split GPU design.

iWave doesn’t specifically name these coprocessors except to list features including a “4K H.265 decode and 1080p H.264 enc/dec capable VPU, 16-Shader 3D (Vec4), and Enhanced Vision Capabilities (via GPU).” The SoC is also said to offer a “dual failover-ready display controller.” The CPUs, meanwhile, are touted for their “full chip hardware virtualization capabilities.”

Inside the iW-RainboW-G27M

Like iWave’s SMARC 2.0 form factor Snapdragon 820 SOM, the iW-RainboW-G27M supports Linux and Android, in this case running Android Nougat (7.0) or higher. (Toradex’s Apalis iMX8 supports Linux, and also supports FreeRTOS running on the Cortex-M4F MCUs.)

Like Toradex, iWave is not promoting the automotive angle that was originally pushed by NXP. iWave’s module is designed to “offer maximum performance with higher efficiency for complex embedded application of consumer, medical and industrial embedded computing applications,” says iWave.

Like the QuadMax based Apalis iMX8, as well as most of the i.MX8M products we’ve seen, the iW-RainboW-G27M supports up to 4 GB LPDDR4 RAM and up to 16 GB eMMC. iWave notes that the RAM and eMMC are “expandable,” but does not say to what capacities. There’s also a microSD slot and 256 MB of optional QSPI flash.

Whereas Apalis iMX8 has a single GbE controller, iWave’s COM has two. It similarly offers onboard 802.11ac Wi-Fi and Bluetooth (4.1). The Microchip ATWILC3000-MR110CA module, which juts out a bit on one side, is listed by Digi-Key as 802.11b/g/n, but iWave has it as 802.11ac.

Interfaces expressed via the SMARC edge connector include 2x GbE, 2x USB 3.0 host (4-port hub), 4x USB 2.0 host, and USB 2.0 OTG. Additional SMARC I/O includes 3x UART (2x with CTS & RTS), 2x CAN, 2x I2C, 12x GPIO, and single PCIe, SATA, debug UART, SD, SPI and QSPI

Media features include an HDMI/DP transmitter, dual-channel LVDS or MIPI-DSI, and an SSI/I2S audio interface. iWave also lists HDMI, 2x LVDS, SPDIF, and ESAI separately under “expansion connector interfaces.” Other expansion I/O is said to include MLB, CAN and GPIO.

The 5 V module supports -40 to 80°C temperatures. There is no mention of a carrier board.

Further information

No pricing or availability was listed for the iW-RainboW-G27M, but a form is available for requesting a quote. More information may be found on iWave’s iW-RainboW-G27M product page.

iWave | www.iwavesystems.com

This article originally appeared on LinuxGizmos.com on March 13.

April Circuit Cellar: Sneak Preview

The April issue of Circuit Cellar magazine is coming soon. And we’ve got a healthy serving of embedded electronics articles for you. Here’s a sneak peak.

Not a Circuit Cellar subscriber?  Don’t be left out! Sign up today:


Here’s a sneak preview of April 2018 Circuit Cellar:


IoT: From Gateway to Cloud
In this follow on to our March “IoT: Device to Gateway” feature, this time we look at technologies and solutions for the gateway to cloud side of IoT.  Circuit Cellar Chief Editor Jeff Child examines the tools and services available to get a cloud-connected IoT implementation up and running.

Texting and IoT Embedded Devices (Part 2)
In Part 1, Jeff Bachiochi laid the groundwork for describing a project involving texting. He puts that into action this, showing how to create messages on his Espressif System’s ESP8266EX-based device to be sent to an email account and end up with those messages going as texts to a cell phone.

Internet of Things Security (Part 2)
In this next part of his article series on IoT security, Bob Japenga takes a look at side-channel attacks. What are they? How much of a threat are they? And how can we prevent them?

Product Focus: 32-Bit Microcontrollers
As the workhorse of today’s embedded systems, 32-bit microcontrollers serve a wide variety of embedded applications—including the IoT. This Product Focus section updates readers on these trends and provides a product album of representative 32-bit MCU products.


Graphics, Video and Displays
Thanks to advances in displays and innovations in graphics ICs, embedded systems can now routinely feature sophisticated graphical user interfaces. Circuit Cellar Chief Editor Jeff Child dives into the latest technology trends and product developments in graphics, video and displays.

Color Recognition and Segmentation in Real-time
Vision systems used to require big, multi-board systems—but not anymore. Learn how two Cornell undergraduates designed a hardware/software system that accelerates vision-based object recognition and tracking using an FPGA SoC. They made a min manufacturing line to demonstrate how their system can accurately track and categorize manufactured candies carried along a conveyor belt.


Component tolerance
We perhaps take for granted sometimes that the tolerances of our electronic components fit the needs of our designs. In this article, Robert Lacoste takes a deep look into the subject of tolerances, using the simple resistor as an example. He goes through the math to help you better understand accuracy and drift along with other factors.

Understanding the Temperature Coefficient of Resistance
Temperature coefficient of resistance (TCR) is the calculation of a relative change of resistance per degree of temperature change. Even though it’s an important spec, different resistor manufacturers use different methods for defining TCR. In this article, Molly Bakewell Chamberlin examines TCR and its “best practice” interpretations using Vishay Precision Group’s vast experience in high-precision resistors.

Designing of Complex Systems
While some commercial software gets away without much qualification during development, the situation is very different when safety in involved. For aircraft, vehicles or any complex system where failure unacceptable, this means adhering to established standards throughout the development life cycle. In this article, George Novacek tackles these issues and examines some of these standards namely ARP4754.


Build a Marginal Oscillator Proximity Switch
A damped or marginal oscillator will switch off when energy is siphoned from its resonant LC tank circuit. In his article, Dev Gualtieri presents a simple marginal oscillator that detects proximity to a small steel screw or steel plate. It lights an LED, and the LED can be part of an optically-isolated solid-state relay.

Obsolescence-Proof Your UI (Part 1)
After years of frustration dealing with graphical interface technologies that go obsolete, Steve Hendrix decided there must be a better way. Knowing that web browser technology is likely to be with us for a long while, he chose to build a web server that could perform common operations that he needed on the IEEE-488 bus. He then built it as a product available for sale to others—and it is basically obsolescence-proof.



Xeon D and NVIDIA GPUs Share COMe Board

Connect Tech has announced the release of its new COM Express Type 7 + GPU Embedded System. This system combines Intel Xeon D (Server Class) x86 processors with high-end NVIDIA Quadro and Tesla GPUs, all in a small form factor embedded system. This V7G system is not a replacement to Connect Tech’s VXG Type 6 systems, but rather a next-generation platform that incorporates the new COM Express Type 7 PICMG standard and employs 10 Gbit Ethernet connectivity and expanded PCI Express interfaces.
Embedded system developers can choose from highest-end, highest-performance models or from low-powered models all ideal for high-end encode/decode video applications or GPGPU CUDA processing, Deep Learning and Artificial Intelligence applications. This embedded computer exposes all of the latest generation interconnect including: 10 Gbit Ethernet and Gbit Ethernet, USB 3.0 and 2.0, HDMI, SATA III, GPIO, I2C, M.2, Mini PCIe. The system uses PC-style connectors for ease of cabling and packaging.

Connect Tech | www.connecttech.com

3.5″ SBC Serves up Skylake Processors

COMMELL has announced its LS-37K 3.5-inch embedded mini-board based on Intel 6th/7th generation FCLGA1151 Skylake / Kaby Lake Core processor family and Xeon E3-1200 v5 processor. The Skylake PC is claimed to deliver 30 percent better performance than a PC base on Ivy Bridge architecture, 20 percent better performance than a PC based on Haswell, and 10 percent better performance than a Broadwell PC.

LS-37K-3D8The LS-37K desktop 3.5-inch mini-board platform supports DDR4 memory DIMM 1866/2133 MHz up to 16 GB. The platform is based on Intel HD530 (Skylake) HD630, (Kaby Lake) and HD P530 (Xeon E3-1200v5). For graphics, the Skylake GPU offers 24 execution units (EUs) clocked at up to 1150Mhz (depending on the CPU model). The revised video engine now decodes H.265/HEVC completely in hardware and thereby much more efficiently than before, and HD Graphics 630 GPU is largely identical to the 530 found in Skylake, The only real upgrade here is the HEVC and VP9 support. LS-37K Displays can be connected via 1 VGA, 1 LVDS, 1 DVI, 1 HDMI and one DP port, up to three displays can be controlled simultaneously.

LS-37K offers lots of features including high-speed data transfer interfaces such as 4 x USB3.0 and 2 x SATAIII, equipped with dual Gigabit Ethernet (One of the dual LAN with iAMT 11.0 supported), and comes with PS/2 port, 5 x RS232 and 1 x RS232/422/485, 4 x USB2.0, Intel® High Definition Audio, and 1 Mini PCIe socket (supporting mSATA) and 9 to 30 VDC input.

COMMELL | www.commell.com

Current Multipliers Improve Processor Performance

Vicor has announced the introduction of Power-on-Package modular current multipliers for high performance, high current, CPU/GPU/ASIC (“XPU”) processors. By freeing up XPU socket pins and eliminating losses associated with delivery of current from the motherboard to the XPU, Vicor’s Power-on-Package solution enables higher current delivery for maximum XPU performance.

In response to the ever-increasing demands of high performance applications–artificial intelligence, machine learning, big data mining—XPU operating currents have risen to Power-on-Package-Enables-Higher-Performance-for-Artificial-Intelligence-Processorshundreds of Amperes. Point-of-Load power architectures in which high current power delivery units are placed close to the XPU, mitigate power distribution losses on the motherboard but do nothing to lessen interconnect challenges between the XPU and the motherboard. With increasing XPU currents, the remaining short distance to the XPU—the “last inch”—consisting of motherboard conductors and interconnects within the XPU socket has become a limiting factor in XPU performance and total system efficiency.

Vicor’s new Power-on-Package Modular Current Multipliers (“MCMs”) fit within the XPU package to expand upon the efficiency, density, and bandwidth advantages of Vicor’s Factorized Power Architecture, already established in 48 V Direct-to-XPU motherboard applications by early adopters. As current multipliers, MCMs mounted on the XPU substrate under the XPU package lid, or outside of it, are driven at a fraction (around 1/64th) of the XPU current from an external Modular Current Driver (MCD). The MCD, located on the motherboard, drives MCMs and accurately regulates the XPU voltage with high bandwidth and low noise. The solution profiled today, consisting of two MCMs and one MCD, enables delivery of up to 320 A of continuous current to the XPU, with peak current capability of 640 A.

With MCMs mounted directly to the XPU substrate, the XPU current delivered by the MCMs does not traverse the XPU socket. And, because the MCD drives MCMs at a low current, power from the MCD can be efficiently routed to MCMs reducing interconnect losses by 10X even though 90% of the XPU pins typically required for power delivery are reclaimed for expanded I/O functionality. Additional benefits include a simplified motherboard design and a substantial reduction in the minimum bypass capacitance required to keep the XPU within its voltage limits.

Multiple MCMs may be operated in parallel for increased current capability. The small (32mm x 8mm x 2.75mm) package and low noise characteristics of the MCM make it suitable for co-packaging with noise-sensitive, high performance ASICs, GPUs and CPUs. Operating temperature range is -40°C to +125°C. These devices represent the first in a portfolio of Power-on-Package solutions scalable to various XPU needs.

Vicor | www.vicorpower.com

Arduino-Based Hand-Held Gaming System

gameduino2-WEBJames Bowman, creator of the Gameduino game adapter for microcontrollers, recently made an upgrade to the system adding a Future Technology Devices International (FTDI) FT800 chip to drive the graphics. Associate Editor Nan Price interviewed James about the system and its capabilities.

NAN: Give us some background. Where do you live? Where did you go to school? What did you study?


James Bowman

 JAMES: I live on the California coast in a small farming village between Santa Cruz and San Francisco. I moved here from London 17 years ago. I studied computing at Imperial College London.

NAN: What types of projects did you work on when you were employed by Silicon Graphics, 3dfx Interactive, and NVIDIA?

JAMES: Always software and hardware for GPUs. I began in software, which led me to microcode, which led to hardware. Before you know it you’ve learned Verilog. I was usually working near the boundary of software and hardware, optimizing something for cost, speed, or both.

NAN: How did you come up with the idea for the Gameduino game console?

JAMES: I paid for my college tuition by working as a games programmer for Nintendo and Sega consoles, so I was quite familiar with that world. It seemed a natural fit to try to give the Arduino some eye-catching color graphics. Some quick experiments with a breadboard and an FPGA confirmed that the idea was feasible.

NAN: The Gameduino 2 turns your Arduino into a hand-held modern gaming system. Explain the difference from the first version of Gameduino—what upgrades/additions have been made?


The Gameduino2 uses a Future Technology Devices International chip to drive its graphics

JAMES: The original Gameduino had to use an FPGA to generate graphics, because in 2011 there was no such thing as an embedded GPU. It needs an external monitor and you had to supply your own inputs (e.g., buttons, joysticks, etc.). The Gameduino 2 uses the new Future Technology Devices International (FTDI) FT800 chip, which drives all the graphics. It has a built-in color resistive touchscreen and a three-axis accelerometer. So it is a complete game system—you just add the CPU.

NAN: How does the Arduino factor into the design?


An Arduino, Ethernet adapter, and a Gameduino

 JAMES: Arduino is an interesting platform. It is 5 V, believe it or not, so the design needs a level shifter. Also, the Arduino is based on an 8-bit microcontroller, so the software stack needs to be carefully built to provide acceptable performance. The huge advantage of the Arduino is that the programming environment—the IDE, compiler, and downloader—is used and understood by hundreds of thousands of people.

 NAN: Is it easy or possible to customize the Gameduino 2?

 JAMES: I would have to say no. The PCB itself is entirely surface mount technology (SMT) and all the ICs are QFNs—they have no accessible pins! This is a long way from the DIP packages of yesterday, where you could change the circuit by cutting tracks and soldering onto the pins.

I needed a microscope and a hot air station to make the Gameduino2 prototype. That is a long way from the “kitchen table” tradition of the Arduino. Fortunately the Arduino’s physical design is very customization-friendly. Other devices can be stacked up, adding networking, hi-fi sound, or other sensor inputs.

 NAN: The Gameduino 2 project is on Kickstarter through November 7, 2013. Why did you decide to use Kickstarter crowdfunding for this project?

 JAMES: Kickstarter is great for small-scale inventors. The audience it reaches also tends to be interested in novel, clever things. So it’s a wonderful way to launch a small new product.

NAN: What’s next for Gameduino 2? Will the future see a Gameduino 3?

 JAMES: Product cycles in the Arduino ecosystem are quite long, fortunately, so a Gameduino 3 is distant. For the Gameduino 2, I’m writing a book, shipping the product, and supporting the developer community, which will hopefully make use of it.