September Circuit Cellar: Sneak Preview

The September issue of Circuit Cellar magazine is coming soon. Clear your decks for a new stack of in-depth embedded electronics articles prepared for you to enjoy.

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


Motion Control for Robotics
Motion control technology for robotic systems continues to advance, as chip- and board-level solutions evolve to meet new demands. These involve a blending of precise analog technologies to control position, torque and speed with signal processing to enable accurate, real-time motor control. Here, Circuit Cellar’s Editor-in-Chief, Jeff Child, looks the latest technology and product advances in motion control for robotics.

Electronic Speed Control (Part 3)
Radio-controlled drones are one among many applications that depend on the use of an Electronic Speed Controller (ESC) as part of its motor control design. After observing the operation of a number of ESC modules, in this part Jeff Bachiochi focuses in more closely on the interaction of the ESC with the BLDC motor.


Product Focus: IoT Gateways
IoT gateways are a smart choice to facilitate bidirectional communication between IoT field devices and the cloud. Gateways also provide local processing and storage capabilities for offline services as well as near real-time management and control of edge devices. This Product Focus section updates readers on these technology trends and provides a product gallery of representative IoT gateways.

Wireless Weather Station
Integrating wireless technologies into embedded systems has become much easier these days. In this project article, Raul Alvarez Torrico describes his home-made wireless weather station that monitors ambient temperature, relative humidity, wind speed and wind direction, using Arduino and a pair of cheap Amplitude Shift Keying (ASK) radio modules.


Frequency Modulated DDS
Prompted by a reader’s query, Ed became aware that you can no longer get crystal oscillator modules tuned to specific frequencies. With that in mind, Ed set out to build a “Channel Element” replacement around a Teensy 3.6 board and a DDS module. In this article, Ed Nisley explains how the Teensy’s 32-bit datapath and 180 MHz CPU clock affect the DDS frequency calculations. He then explores some detailed timings.

Power Supplies / Batteries
Sometimes power decisions are left as an afterthought in system designs. But your choice of power supply or battery strategy can have a major impact on your system’s capabilities. Circuit Cellar’s Editor-in-Chief, Jeff Child, dives into the latest technology trends and product developments in power supplies and batteries.

Murphy’s Laws in the DSP World (Part 3)
Unpredictable issues crop up when you move from the real world of analog signals and enter the world of digital signal processing (DSP). In Part 3 of this article series, Mike Smith and Mai Tanaka focuses on strategies for how to—or how to try to—avoid Murphy’s Laws when doing DSP.


Virtual Emulation for Drones
Drone system designers are integrating high-definition video and other features into their SoCs. Verifying the video capture circuitry, data collection components and UHD-4K streaming video capabilities found in drones is not trivial. In his article, Mentor’s Richard Pugh explains why drone verification is a natural fit for hardware emulation because emulation is very efficient at handling large amounts of streamed data.

LIDAR 3D Imaging on a Budget
Demand is on the rise for 3D image data for use in a variety of applications, from autonomous cars to military base security. That has spurred research into high precision LIDAR systems capable of creating extremely clear 3D images to meet this demand. Learn how Cornell student Chris Graef leveraged inexpensive LIDAR sensors to build a 3D imaging system all within a budget of around $200.


Velocity and Speed Sensors
Automatic systems require real-life physical attributes to be measured and converted to electrical quantities ready for electronic processing. Velocity is one such attribute. In this article, George Novacek steps through the math, science and technology behind measuring velocity and the sensors used for such measurements.

Recreating the LPC Code Protection Bypass
Microcontroller fuse bits are used to protect code from being read out. How well do they work in practice? Some of them have been recently broken. In this article Colin O’Flynn takes you through the details of such an attack to help you understand the realistic threat model.

FPGA Solutions Evolve to Meet AI Needs

Brainy System ICs

Long gone now are the days when FPGAs were thought of as simple programmable circuitry for interfacing and glue logic. Today, FPGAs are powerful system chips with on-chip processors, DSP functionality and high-speed connectivity.

By Jeff Child, Editor-in-Chief

Today’s FPGAs have now evolved to the point that calling them “systems-on-chips” is redundant. It’s now simply a given that the high-end lines of the major FPGA vendors have general-purpose CPU cores on them. Moreover, the flavors of signal processing functionality on today’s FPGA chips are ideally suited to the kind of system-oriented DSP functions used in high-end computing. And even better, they’ve enabled AI (Artificial Intelligence) and Machine Learning kinds of functionalities to be implemented into much smaller, embedded systems.

In fact, over the past 12 months, most of the leading FPGA vendors have been rolling out solutions specifically aimed at using FPGA technology to enable AI and machine learning in embedded systems. The two main FPGA market leaders Xilinx and Intel’s Programmable Solutions Group (formerly Altera) have certainly embraced this trend, as have many of their smaller competitors like Lattice Semiconductor and QuickLogic. Meanwhile, specialists in so-called e-FPGA technology like Archonix and Flex Logix have their own compelling twist on FPGA system computing.

Project Brainwave

Exemplifying the trend toward FPGAs facilitating AI processing, Intel’s high-performance line of FPGAs is its Stratix 10 family. According to Intel, the Stratix 10 FPGAs are capable of 10 TFLOPS, or 10 trillion floating point operations per second (Figure 1). In May Microsoft announced its Microsoft debuted its Azure Machine Learning Hardware Accelerated Models powered by Project Brainwave integrated with the Microsoft Azure Machine Learning SDK. Azure’s architecture is developed with Intel FPGAs and Intel Xeon processors.

Figure 1
Stratix 10 FPGAs are capable of 10 TFLOPS or 10 trillion floating point operations per second.

Intel says its FPGA-powered AI is able to achieve extremely high throughput that can run ResNet-50, an industry-standard deep neural network requiring almost 8 billion calculations without batching. This is possible using FPGAs because the programmable hardware—including logic, DSP and embedded memory—enable any desired logic function to be easily programmed and optimized for area, performance or power. And because this fabric is implemented in hardware, it can be customized and can perform parallel processing. This makes it possible to achieve orders of magnitudes of performance improvements over traditional software or GPU design methodologies.

In one application example, Intel cites an effort where Canada’s National Research Council (NRC) is helping to build the next-generation Square Kilometer Array (SKA) radio telescope to be deployed in remote regions of South Africa and Australia, where viewing conditions are most ideal for astronomical research. The SKA radio telescope will be the world’s largest radio telescope that is 10,000 times faster with image resolution 50 times greater than the best radio telescopes we have today. This increased resolution and speed results in an enormous amount of image data that is generated by these telescopes, processing the equivalent of a year’s data on the Internet every few months.

NRC’s design embeds Intel Stratix 10 SX FPGAs at the Central Processing Facility located at the SKA telescope site in South Africa to perform real-time processing and analysis of collected data at the edge. High-speed analog transceivers allow signal data to be ingested in real time into the core FPGA fabric. After that, the programmable logic can be parallelized to execute any custom algorithm optimized for power efficiency, performance or both, making FPGAs the ideal choice for processing massive amounts of real-time data at the edge.

ACAP for Next Gen

For its part, Xilinx’s high-performance product line is its Virtex UltraScale+ device family (Figure 2). According to the company, these provide the highest performance and integration capabilities in a FinFET node, including the highest signal processing bandwidth at 21.2 TeraMACs of DSP compute performance. They deliver on-chip memory density with up to 500 Mb of total on-chip integrated memory, plus up to 8 GB of HBM Gen2 integrated in-package for 460 GB/s of memory bandwidth. Virtex UltraScale+ devices provide capabilities with integrated IP for PCI Express, Interlaken, 100G Ethernet with FEC and Cache Coherent Interconnect for Accelerators (CCIX).

Figure 2
Virtex UltraScale+ FPGAs provide a signal processing bandwidth at 21.2 TeraMACs. They deliver on-chip memory density with up to 500 Mb of total on-chip integrated memory, plus up to 8 GB of HBM Gen2 integrated in-package for 460 GB/s of memory bandwidth.

Looking to the next phase of system performance, Xilinx in March announced its strategy toward a new FPGA product category it calls its adaptive compute acceleration platform (ACAP). Touted as going beyond the capabilities of an FPGA, an ACAP is a highly integrated multi-core heterogeneous compute platform that can be changed at the hardware level to adapt to the needs of a wide range of applications and workloads. An ACAP’s adaptability, which can be done dynamically during operation, delivers levels of performance and performance per-watt that is unmatched by CPUs or GPUs, says Xilinx… …

Read the full article in the August 337 issue of Circuit Cellar

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Note: We’ve made the October 2017 issue of Circuit Cellar available as a free sample issue. In it, you’ll find a rich variety of the kinds of articles and information that exemplify a typical issue of the current magazine.

August Circuit Cellar: Sneak Preview

The August issue of Circuit Cellar magazine is coming soon. Be on the lookout for a whole shipload of top-notch embedded electronics articles for you to enjoy.

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


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


FPGA System Design
Long gone now are the days when FPGAs were thought of as simple programmable circuitry for interfacing and glue logic. Today, FPGAs are powerful system chips with on-chip processors, signal processing functionality and rich offerings or high-speed connectivity. Here, Circuit Cellar’s Editor-in-Chief, Jeff Child, looks at the latest technology and trends in FPGA system design.

Managing FPGA Design Complexity
Modern FPGAs can contain millions of logic gates and thousands of embedded DSP processors allowing FPGA hardware designers to create extremely sophisticated and complex application-specific hardware functions. In this article, Pentek’s Bob Sgandurra explores how today’s FPGA technology has revamped the roles of both hardware and software engineers as well as how dealing with on-chip IP adds new layers of complexity.


Product Focus: Small and Tiny Embedded Boards
An amazing amount of computing functionality can be squeezed on to a small form factor board these days. These company—and even tiny—board-level products meet the needs of applications where extremely low SWaP (size, weight and power) beats all other demands. This Product Focus section updates readers on this technology trend and provides a product album of representative small and tiny embedded boards.

Microcontrollers and Processors
Today’s crop of microcontrollers and embedded processors provide a rich continuum of features, functions and capabilities. It’s hard to tell anymore where the dividing line is, especially when a lot of them use the same CPU cores. Circuit Cellar’s Editor-in-Chief, Jeff Child, delves into the technology and product trends of MCUs and embedded processors.


Murphy’s Laws in the DSP World (Part 2)
Many unexpected issues come into play when you move from the real world of analog signals and enter the world of digital signal processing (DSP). Part 2 of this article series by Michael Smith, Mai Tanaka and Ehsan Shahrabi Farahani charges forward introducing “Murphy’s Laws of DSP” #7, #8 and #9 and looks at the spectral analysis of DSP signals.

Signature Analyzer Uses NXP MCU
Doing a signature analysis of a signal used to require an oscilloscope to display your results. In this article, Brian Millier shows how you can build a free-standing tester that uses mostly just the internal peripherals of an NXP ARM microcontroller. He described how the tester operates and how he implemented it using a Teensy 3.5 development module and an intelligent 4.3-inch TFT touch-screen display.

Pitfalls of Filtering Pulsed Signals
Filtering pulsed signals can be a tricky prospect. Using a recent customer implementation as an example, Robert Lacoste highlights various alternative approaches and describes the key concepts involved. Simulation results are provided to help readers understand what’s going on.


Electronic Speed Control (Part 2)
In Part 1, Jeff Bachiochi discussed the mechanical differences between DC brushed and brushless DC (BLDC) motors. This time he dives into basics of an Electronic Speed Controller’s operations and its circuitry. And all this is illustrated via his ESC-based project that uses a Microchip PIC MCU.

Build an Audio Response Light Display
Light shows have been a part of entertainment situations seemingly forever, but the technology has evolved over time. These light shows have their origin in the primitive “light organs” of the 1960s in which each spectral band had its own color that pulsed in intensity with audio amplitudes within its range of frequencies. In this article, Devlin Gualtieri discusses his circuit design that implements a light organ using today’s IC and LED technologies.


Internet of Things Security (Part 4)
In this next part of his article series on IoT security, Bob Japenga looks at how checklists and the common criteria framework can help us create more secure IoT devices. He covers how to create a list of security assets and to establish threat checklists that identify all the threats to your security assets.

Thermoelectric Cooling (Part 2)
In Part 1 George Novacek described how he built a test chamber using some electronics combined with components salvaged from his thermoelectric water cooler. To confirm his test results, he purchased another thermoelectric cooler and repeated the tests. In Part 2 he covers the results of these tests along with some theoretical performance calculations.

Zynq SoC SOM Module Enabled With HSR/PRP IP

iWave Systems has partnered with SoC-e for enabling HSR/PRP IP on iWave’s Zynq 7000 SoC SOM Module. iWave has rigorously validated SoC-e’s High-availability Seamless Redundancy (HSR) and Parallel Redundancy Protocol (PRP) IP Protocol on our Zynq 7000 SoC based SOM module. iWave’s Zynq 7000 SoC SOM and SoC-e’s HSR/PRP Switch IP Core reduce the time-to-market and simplifying design complexity. SOC-e develops IP portfolios for leading-edge networking and synchronization technologies for time critical systems.The Zynq-7000 programmable SoC family integrates the software programmability of an Arm-based processor with the hardware programmability of an FPGA, enabling key analytics and hardware acceleration while integrating CPU, DSP, ASSP and mixed signal functionality on a single device. The iW-RainboW-G28M (Zynq 7000 Board) is a featured-full and ready to-operate embedded software and advanced circuit development kit built around the smallest member from the Xilinx Zynq-7000 family, the Z-7010.

The Zynq-7000 SOM / Development Kit is based on the Xilinx All Programmable System-on-Chip architecture, which firmly incorporates a single / Dual Cortex A9 with Xilinx 7-series FPGA logic. At the point when combined with the rich set of media and connectivity peripherals accessible on the Zynq 7000 SOM, the Zynq Z-7007S, Z-7014S, Z-7010, Z-7020, can host an entire design system.

Memories, 512 MB DDR3 (Expandable to 1 GB) or 512 MB NAND Flash (Expandable), that are on-board, video and sound I/O, USB 2.0 OTG, Gigabit Ethernet and SD (4-bit) will have your board up-and-running with no extra hardware required. Moreover, PMIC with RTC bolster connectors is accessible to put any design on a simple development way.

The iW-RainboW-G28M gives an ultra-cost to embedded designers that don’t require the high-thickness I/O of the FMC connector yet at the same time wish to use the enormous preparing force and extensibility of the Zynq AP SoC architecture.

iWave Systems |

Multiphase PMICs Boast High Efficiency and Small Footprint

Renesas Electronics has announced three programmable power management ICs (PMICs) that offer high power efficiency and small footprint for application processors in smartphones and tablets: the ISL91302B, ISL91301A, and ISL91301B PMICs. The PMICs also deliver power to artificial intelligence (AI) processors, FPGAs and industrial microprocessors (MPUs). They are also well-suited for powering the supply rails in solid-state drives (SSDs), optical transceivers, and a wide range of consumer, industrial and networking devices. The ISL91302B dual/single output, multiphase PMIC provides up to 20 A of output current and 94 percent peak efficiency in a 70 mm2 solution size that is more than 40% smaller than competitive PMICs.
In addition to the ISL91302B, Renesas’ ISL91301A triple output PMIC and ISL91301B quad output PMIC both deliver up to 16 A of output power with 94% peak efficiency. The new programmable PMICs leverage Renesas’ R5 Modulation Technology to provide fast single-cycle transient response, digitally tuned compensation, and ultra-high 6 MHz (max) switching frequency during load transients. These features make it easier for power supply designers to design boards with 2 mm x 2 mm, 1mm low profile inductors, small capacitors and only a few passive components.

Renesas PMICs also do not require external compensation components or external dividers to set operating conditions. Each PMIC dynamically changes the number of active phases for optimum efficiency at all output currents. Their low quiescent current, superior light load efficiency, regulation accuracy, and fast dynamic response significantly extend battery life for today’s feature-rich, power hungry devices.

Key Features of ISL91302B PMIC:

  • Available in three factory configurable options for one or two output rails:
    • Dual-phase (2 + 2) configuration supporting 10 A from each output
    • Triple-phase (3 + 1) configuration supporting 15 A from one output and  5A from the second output
    • Quad-phase (4 + 0) configuration supporting 20A from one output
  • Small solution size: 7 mm x 10 mm for 4-phase design
  • Input supply voltage range of 2.5 V to 5.5 V
  • I2C or SPI programmable Vout from 0.3 V to 2 V
  • R5 modulator architecture balances current loads with smooth phase adding and dropping for power efficiency optimization
  • Provides 75 μA quiescent current in discontinuous current mode (DCM)
  • Independent dynamic voltage scaling for each output
  • ±0.7percent system accuracy for -10°C to 85°C with remote voltage sensing
  • Integrated telemetry ADC senses phase currents, output current, input/output voltages, and die temperature, enabling PMIC diagnostics during operation
  • Soft-start and fault protection against under voltage (UV), over voltage (OV), over current (OC), over temperature (OT), and short circuit

Key Features of ISL91301A and ISL91301B PMICs

  • Available in two factory configurable options:
    • ISL91301A: dual-phase, three output rails configured as 2+1+1 phase
    • ISL91301B: single-phase, four output rails configured as 1+1+1+1 phase
  • 4A per phase for 2.8 V to 5.5 V supply voltage
  • 3A per phase for 2.5 V to 5.5 V supply voltage
  • Small solution size: 7 mm x 10 mm for 4-phase design
  • I2C or SPI programmable Vout from 0.3 V to 2 V
  • Provides 62μA quiescent current in DCM mode
  • Independent dynamic voltage scaling for each output
  • ±0.7percent system accuracy for -10°C to 85°C with remote voltage sensing
  • Soft-start and fault protection against UV, OV, OC, OT, and short circuit

Pricing and Availability

The ISL91302B dual/single output PMIC is available now in a 2.551 mm x 3.670 ball WLCSP package and is priced at $3.90 in 1k quantities. For more information on the ISL91302B, please visit:

The ISL91301A triple-output PMIC and ISL91301B quad-output PMIC are available now in 2.551 mm x 2.87 mm, 42-ball WLCSP packages, both priced at $3.12 in 1k quantities. For more information on the ISL91301A, please visit: For more information on the ISL91301B, please visit:

Renesas Electronics |

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.

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.



Compact Power Regulator Targets FPGAs, GPUs and ASICs

Analog Devices has announced the Power by Linear LTM4646, a dual 10 A or single 20 A output, step-down µModule point-of-load regulator from 5V or 12V input supply rails. The LTM4646 includes the inductors, MOSFETs, a DC/DC controller and supporting components and is housed in a 11.25 mm x 15 mm x 5.01 mm BGA package. Compared to the prior 2 x single 10 A output module solutions, the LTM4646 reduces the solution size of more than 25%.
With its dual regulator design, small package size, and precise voltage regulation, the LTM4646 meets the PCB area constraints of densely populated system boards to power low voltage and high current devices such as FPGAs, ASICs, microprocessors and GPUs. Applications include PCIe boards, communication infrastructure, cloud computing-based systems, as well as medical, industrial, and test and measurement equipment.

Total output voltage DC accuracy is guaranteed at ±1.5% over line, load and temperature (–40°C to 125°C). Moreover, the onboard remote sense amplifiers on both outputs compensate for voltage drop caused by trace impedance of the PC board due to large load currents. The LTM4646 has selectable internal or external feedback loop compensation, enabling users to optimize loop stability and transient performance while minimizing the number of output capacitors. The peak efficiency at 12 VIN to 1.0 VOUT is 86%. With 200LFM air flow, the LTM4646 delivers a full 20A  continuously up to 85°C ambient. The current mode architecture allows multiphase parallel operation to increase output current with very good current sharing.

Standalone, the LTM4646 operates from 4.5 V to 20 V input range. When 5 V external bias is available, the device can operate from 2.375 V. The output voltages are adjustable from 0.6 V to 5.5 V, enabling the device to generate not only low voltage for digital devices but also 2.5 V, 3.3 V and  5V, which are commonly needed in system bus voltages. The switching frequency can be programmed from 250 kHz to 1.3 MHz with one resistor, and can also be synchronized to an external clock ranging from 300 kHz to 1 MHz for noise-sensitive applications. Additionally, it features overvoltage and overcurrent protection. The LTM4646 operates from –40°C to 125°C.

Summary of Features: LTM4646

  •     Dual 10A or Single 20A Output
  •     Wide Input Voltage Range: 4.5V to 20V
  •     2.375VMIN with CPWR Bias
  •     Output Voltage Range: 0.6V to 5.5V
  •     ±1.5% Maximum Total DC Output Error
  •     Multiphase Current Sharing
  •     Differential Remote Sense Amplifier, Each Channel
  •     Internal or External Compensation
  •     11.25mm x 15mm x 5.01mm BGA Package
  •     BGA Ball Finishes Available: SAC305 (RoHS), SnPb (63/37)


Linear Technology |

30 A Encapsulated Digital Power Modules

Renesas Electronics has announced two new fully encapsulated digital DC/DC PMBus power modules that board high power density and efficiency. The dual ISL8274M operates from a 5 V or 12 V power rail, provides two 30 A outputs and up to 95.5% peak efficiency in a compact 18 mm x 23 mm2 footprint. The new ZL9024M operates from a 3.3V rail and outputs 33 A of power in a 17 mm x19 mm2 footprint. They deliver point-of-load (POL) conversions for advanced FPGAs, DSPs, ASICs and memory used in servers, telecom, datacom, optical networking and storage equipment. Both devices are easy-to-use, PMBus-configurable power supplies that include a controller, MOSFETs, inductor and passives encapsulated inside a module that increases available board space and reduces bill of materials (BOM).

The ISL8274M and ZL9024M digital power modules leverage Renesas’ patented ChargeMode control architecture, which provides the highest efficiencies with better than 90% on most conversions. The power modules also provide a single clock cycle fast transient response to output current load steps common in FPGAs and DSPs that process power bursts. Their compensation-free design keeps the modules stable regardless of output capacitor changes due to temperature, variation or aging. Eliminating the need for an external discrete compensation network also saves board space and additional BOM cost. The ISL8274M supports input voltages from 4.5 V to 1 4V, while the ZL9024M accepts input voltages from 2.75 V to 4 V. Both modules offer adjustable output voltages as low as 0.6 V.

The encapsulated modules use Renesas’ proprietary High Density Array (HDA) package, which offers unmatched electrical and thermal performance through a single-layer conductive substrate that reduces lead inductance and dissipates heat primarily through the system board. The HDA’s copper lead-frame structure allows the modules to operate at full load over a wide temperature range with no airflow or heatsinks. The ISL8274M and ZL9024M also provide several protection features that ensure safe operations under abnormal operating conditions, further enhancing their robustness and reliability.

Key Features of the ISL8274M Digital Power Module include:

  • 30 A dual digital switch mode power supply with input voltage range from 4.5 V to 14 V and programmable Vout from 0.6 V to 5 V
  • PMBus-enabled solution for full system configuration, telemetry and monitoring of all conversions and operating parameters
  • Programmable Vout, soft-start, soft-stop, sequencing, margining and under-voltage, over-voltage, under-current, over-current, under temperature and over-temperature
  • Monitors Vin, Vout, Iout, temperature, duty cycle, switching frequency, and faults
  • Power good indicator, and ±1.2% Vout accuracy over line, load, and temperature
  • Pin-strap mode using external resistors for standard settings
  • Internal nonvolatile memory saves module configuration parameters and fault logging

Key Features of the ZL9024M Digital Power Module include:

  • 33 A digital switch mode power supply with input voltage range from 2.75 V to 4 V and programmable Vout from 0.6 V to 1.5 V
  • PMBus-enabled solution for full system configuration, telemetry and monitoring of all conversions and operating parameters
  • Programmable Vout, soft-start, soft-stop, sequencing, margining and under-voltage, over-voltage, under-current, over-current, under temperature and over-temperature
  • Monitors Vin, Vout, Iout, temperature, duty cycle, switching frequency and faults
  • Power good indicator, and ±1.2% Vout accuracy over line, load, and temperature
  • Pin-strap mode using external resistors for standard settings
  • Internal nonvolatile memory saves module configuration parameters and fault logging


The ISL8274M is available now in a thermally enhanced 18 mm x 23 mm x 7.5 mm HDA package, and is priced at $39 (1,000). An ISL8274MEVAL1Z evaluation board is available for $150.

The ZL9024M is available now in a thermally enhanced 17 mm x 19 mm x 3.5 mm HDA package, and is priced at $29 (1,000s). The ZL9024MEVAL1Z evaluation board is available for $95.

Renesas Electronics |

January Circuit Cellar: Sneak Preview

The January issue of Circuit Cellar magazine is coming soon. And it’s got a robust selection of embedded electronics articles for you. Here’s a sneak peak.

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


                                     IMPROVING EMBEDDED SYSTEM DESIGNS

Special Feature: Powering Commercial Drones
The amount of power a commercial drone can draw on has a direct effect on how long it can stay flying as well as on what tasks it can perform. Circuit Cellar Chief Editor Jeff Child examines solar cells, fuel cells and other technology options for powering commercial drones.

CC 330 CoverFPGA Design: A Fresh Take
Although FPGAs are well established technology, many embedded systems developers—particularly those used the microcontroller realm—have never used them before. In this article, Faiz Rahman takes a fresh look a FPGAs for those new to designing them into their embedded systems.

Product Focus: COM Express boards
COM Express boards provide a complete computing core that can be upgraded when needed, leaving the application-specific I/O on the baseboard. This brand new Product Focus section updates readers on this technology and provides a product album of representative COM Express products.


LF Resonator Filter
In Ed Nisley’s November column he described how an Arduino-based tester automatically measures a resonator’s frequency response to produce data defining its electrical parameters. This time he examines the resultsand explains a tester modification to measure the resonator’s response with a variable series capacitance.

Technology Spotlight: 5G Technology and Testing
The technologies that are enabling 5G communications are creating new challenges for embedded system developers. Circuit Cellar Chief Editor Jeff Child explores the latest digital and analog ICs aimed at 5G and at the test equipment designed to work with 5G technology.

                                     MICROCONTROLLERS IN EVERYTHING

MCU-based Platform Stabilizer
Using an Inertial Measurement Unit (IMU), two 180-degree rotation servos and a Microchip PCI MCU, three Cornell students implemented a microcontroller-based platform stabilizer. Learn how they used a pre-programmed sensor fusion algorithm and I2C to get the most out of their design.

Designing a Home Cleaning Robot (Part 2)
Continuing on with this four-part article series about building a home cleaning robot, Nishant Mittal this time discusses the mechanical aspect of the design. The robot is based on Cypress Semiconductor’s PSoC microcontroller.

Massage Vest Uses PIC32 MCU
Microcontrollers are being used for all kinds of things these days. Learn how three Cornell graduates designed a low-cost massage vest that pairs seamlessly with a custom iOS app. Using the Microchip PIC32 for its brains, the massage vest has sixteen vibration motors that the user can control to create the best massage possible.


Five Fault Injection Attacks
Colin O’Flynn returns to the topic of fault injection security attacks. To kick off 2018, he summarizes information about five different fault injection attack stories from 2017—attacks you should be thinking about as an embedded designer.

Money Sorting Machines (Part 2)
In part 1, Jeff Bachiochi delved into the interesting world of money sort machines and their evolution. In part 2, he discusses more details about his coin sorting project. He then looks at a typical bill validator implementation used in vending systems.

Overstress Protection
Last month George Novacek reviewed the causes and results of electrical overstress (EOS). Picking up where that left off, in this article he looks at how to prevent EOS/ESD induced damage—starting with choosing properly rated components.

December Circuit Cellar: A Sneak Preview

The December issue of Circuit Cellar magazine is coming soon. Want a sneak peak? We’ve got a great selection of excellent embedded electronics articles for you.

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

 Here’s a sneak preview of December Circuit Cellar:


Special Feature: Electronics for Wearable Devices
Circuit Cellar Chief Editor Jeff Child examines how today’s microcontrollers, sensors and power electronics enable today’s wearable products.

329 Cover Screen CapSimulating a Hammond Tonewheel Organ
(Part 2)

Brian Millier continues this two-part series about simulating the Hammond tonewheel organ using a microcontrollers and DACs. This time he examines a Leslie speaker emulation.

Money Sorting Machines (Part 1)
In this new article series, Jeff Bachiochi looks the science, mechanics and electronics that are key to sorting everything from coins to paper money. This month he discusses a project that uses microcontroller technology to sort coins.

Designing a Home Cleaning Robot (Part 1)
This four-part article series about building a home cleaning robot starts with Nishant Mittal discussing his motivations behind to his design concept, some market analysis and the materials needed.


Designing High Performance GUI
It’s critical to understand the types of performance problems a typical end-user might encounter and the performance metrics relevant to user interface (UI) design. Phil Brumby of Mentor’s Embedded Systems Division examines these and other important UI design challenges.

Building a Robotic Candy Sorter
Learn how a pair of Cornell graduates designed and constructed a robotic candy sort. It includes a three degree of freedom robot arm and a vision system using a Microchip PIC32 and Raspberry Pi module.

Raster Laser Projector Uses FPGA
Two Cornell graduates describe a raster laser projector they designed that’s able to project images in 320 x 240 in monochrome red. The laser’s brightness and mirrors positions are controlled by an FPGA and analog circuitry.


Technology Spotlight: Power-over-Ethernet Solutions
Power-over-Ethernet (PoE) enables the delivery of electric power alongside data on twisted pair Ethernet cabling. Chief Editor Jeff Child explores the latest chips, modules and other gear for building PoE systems.

Component Overstress
When an electronic component starts to work improperly, Two likely culprits are electrical overstress (EOS) and electrostatic discharge (ESD). In his article, George Novacek breaks down the important differences between the two and how to avoid their effects.


Writing the Proposal
In this conclusion to his “Building an Embedded Systems Consulting Company” article series, Bob Japenga takes a detailed look at how to craft a Statement of Work (SOW) that will lead to success and provide clarity for all stakeholders.

Information Theory in a Nutshell
Claude Shannon is credited as one of the pioneers of computer science thanks to his work on Information Theory, informing how data flows in electronic systems. In this article, Robert Lacoste provides a useful exploration of Information Theory in an easily digestible way.

Microsoft Real-time AI Project Leverages FPGAs

At Hot Chips 2017 Microsoft unveiled a new deep learning acceleration platform, codenamed Project Brainwave. The system performs real-time AI. Real-time here means the system processes requests as fast as it receives them, with ultra-low latency. Real-time AI is becoming increasingly important as cloud infrastructures process live data streams, whether they be search queries, videos, sensor streams, or interactions with users.



The Project Brainwave system is built with three main layers: a high-performance, distributed system architecture; a hardware DNN engine synthesized onto FPGAs; and a compiler and runtime for low-friction deployment of trained models. Project Brainwave leverages the massive FPGA infrastructure that Microsoft has been deploying over the past few years. By attaching high-performance FPGAs directly to Microsoft’s datacenter network, they can serve DNNs as hardware microservices, where a DNN can be mapped to a pool of remote FPGAs and called by a server with no software in the loop. This system architecture both reduces latency, since the CPU does not need to process incoming requests, and allows very high throughput, with the FPGA processing requests as fast as the network can stream them.

Project Brainwave uses a powerful “soft” DNN processing unit (or DPU), synthesized onto commercially available FPGAs.  A number of companies—both large companies and a slew of startups—are building hardened DPUs.  Although some of these chips have high peak performance, they must choose their operators and data types at design time, which limits their flexibility.  Project Brainwave takes a different approach, providing a design that scales across a range of data types, with the desired data type being a synthesis-time decision. The design combines both the ASIC digital signal processing blocks on the FPGAs and the synthesizable logic to provide a greater and more optimized number of functional units.  This approach exploits the FPGA’s flexibility in two ways.  First, the developers have defined highly customized, narrow-precision data types that increase performance without real losses in model accuracy.  Second, they can incorporate research innovations into the hardware platform quickly (typically a few weeks), which is essential in this fast-moving space.  As a result, the Microsoft team achieved performance comparable to – or greater than – many of these hard-coded DPU chips but are delivering the promised performance today. At Hot Chips, Project Brainwave was demonstrated using Intel’s new 14 nm Stratix 10 FPGA.

Project Brainwave incorporates a software stack designed to support the wide range of popular deep learning frameworks. They support Microsoft Cognitive Toolkit and Google’s Tensorflow, and plan to support many others. They have defined a graph-based intermediate representation, to which they convert models trained in the popular frameworks, and then compile down to their high-performance infrastructure.

Microsoft |

Don’t Miss Our Bonus Newsletter: FPGA Technologies

As you know, Circuit Cellar’s newsletter covers four key themes each month. But August is a special month with a 5th Tuesday! As result, tomorrow coming to your inbox with be a special bonus newsletter theme: FPGA Technologies. In tomorrow’s newsletter you’ll get news about the products and technologies trends in the FPGA market. FPGAs have sv_gs_diagramevolved to become complete system chips. Today’s FPGAs pack in levels of processing, I/O and memory on one chip that once required several ICs or boards.

Also: We’ve added Drawings for Free Stuff to our weekly newsletters. Make sure you’ve subscribed to the newsletter so you can participate.

Already a Circuit Cellar Newsletter subscriber? Great!
You’ll get your “FPGA Technology” themed newsletter issue tomorrow.

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Don’t be left out! Sign up now:

Remember, our new enhanced weekly CC Newsletter will switch its theme each week, so look for these in upcoming weeks:

Analog & Power. This newsletter content zeros in on the latest developments in analog and power technologies including DC-DC converters, AD-DC converters, power supplies, op-amps, batteries, and more.

Microcontroller Watch. This newsletter keeps you up-to-date on latest microcontroller news. In this section, we examine the microcontrollers along with their associated tools and support products.

IoT Technology Focus. The Internet-of-Things (IoT) phenomenon is rich with opportunity. This newsletter tackles news and trends about the products and technologies needed to build IoT implementations and devices.

Embedded Boards. Embedded boards are critical building blocks around which system developers can build all manor of intelligent systems. The focus here is on both standard and non-standard embedded computer boards.