July Circuit Cellar: Sneak Preview

The July issue of Circuit Cellar magazine is coming soon. And we’ve rustled up a great herd of 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 July 2018 Circuit Cellar:


Wireless Standards and Solutions for IoT  
One of the critical enabling technologies making the Internet-of-Things possible is the set of well-established wireless standards that allow movement of data to and from low-power edge devices. Here, Circuit Cellar’s Editor-in-Chief, Jeff Child, looks at key wireless standards and solutions playing a role in IoT.

Product Focus: IoT Device Modules
The rapidly growing IoT phenomenon is driving demand for highly integrated modules designed to interface with IoT devices. This Product Focus section updates readers on this technology trend and provides a product album of representative IoT interface modules.


EMC Analysis During PCB Layout
If your electronic product design fails EMC compliance testing for its target market, that product can’t be sold. That’s why EMC analysis is such an important step. In his article, Mentor Graphics’ Craig Armenti shows how implementing EMC analysis during the design phase provides an opportunity to avoid failing EMC compliance testing after fabrication.

Extreme Low-Power Design
Wearable consumer devices, IoT sensors and handheld systems are just a few of the applications that strive for extreme low-power consumption. Beyond just battery-driven designs, today’s system developers want no-battery solutions and even energy harvesting. Circuit Cellar’s Editor-in-Chief, Jeff Child, dives into the latest technology trends and product developments in extreme low power.

Op Amp Design Techniques
Op amps can play useful roles in circuit designs linking the real analog world to microcontrollers. Stuart Ball shares techniques for using op amps and related devices like comparators to optimize your designs and improve precision.

Wire Wrapping Revisited
Wire wrapping may seem old fashioned, but this tried and true technology can solve some tricky problems that arise when you try to interconnect different kinds of modules like Arduino, Raspberry Pi and so on. Wolfgang Matthes steps through how to best employ wire wrapping for this purpose and provides application examples.


BLDC Fan Current
Today’s small fans and blowers depend on brushless DC (BLDC) motor technology for their operation. In this article, Ed Nisley explains how these seemingly simple devices are actually quite complex when you measure them in action. He makes some measurements on the motor inside a tangential blower and explores how the data relates to the basic physics of moving air.

Electronic Speed Control (Part 1)
An Electronic Speed Controller (ESC) is an important device in motor control designs, especially in the world of radio-controlled (RC) model vehicles. In Part 1, Jeff Bachiochi lays the groundwork by discussing the evolution of brushed motors to brushless motors. He then explores in detail the role ESC devices play in RC vehicle motors.

MCU-Based Motor Condition Monitoring
Thanks to advances in microcontrollers and sensors, it’s now possible to electronically monitor aspects of a motor’s condition, like current consumption, pressure and vibration. In this article, Texas Instrument’s Amit Ashara steps through how to best use the resources on an MCU to preform condition monitoring on motors. He looks at the signal chain, connectivity issues and A-D conversion.


Verifying Code Readout Protection Claims
How do you verify the security of microcontrollers? MCU manufacturers often make big claims, but sometimes it is in your best interest to verify them yourself. In this article, Colin O’Flynn discusses a few threats against code readout and looks at verifying some of those claimed levels.

Thermoelectric Cooling (Part 1)
When his thermoelectric water color died prematurely, George Novacek was curious whether it was a defective unit or a design problem. With that in mind, he decided to create a test chamber using some electronics combined with components salvaged from the water cooler. His tests provide some interesting insights into thermoelectric cooling.


Quantum Leaps

Input Voltage

–Jeff Child, Editor-in-Chief


Throughout my career, I’ve always been impressed by Intel’s involvement in a wide spectrum of computing and electronics technologies. These range from the mundane and practical on one hand, to forward-looking and disruptive advances on the other. A lot of these weren’t technologies for which Intel ever intended to take direct advantage of over the long term. I think a lot about how Intel facilitated the creation of and early advances in USB. Intel even sold USB chips in the first couple years of USB’s emergence, but stepped aside from that with the knowledge that their main focus was selling processors.

USB made computers and a myriad of consumer electronic devices better and easier to use, and that, Intel knew, advanced the whole industry in which their microprocessors thrived. Today, look around your home, your office and even your car and count the number of USB connectors there are. It’s pretty obvious that USB’s impact has been truly universal.

Aside from mainstream, practical solutions like USB, Intel also continues to participate in the most forward-looking compute technologies. Exemplifying that, in January at the Consumer Electronics Show (CES) show in Las Vegas, Intel announced two major milestones in its efforts to develop future computing technologies. In his keynote address, Intel CEO Brian Krzanich announced the successful design, fabrication and delivery of a 49-qubit superconducting quantum test chip. The keynote also focused on the promise of neuromorphic computing.

In his speech, Krzanich explained that, just two months after delivery of a 17-qubit superconducting test chip, Intel that day unveiled “Tangle Lake,” a 49-qubit superconducting quantum test chip. The chip is named after a chain of lakes in Alaska, a nod to the extreme cold temperatures and the entangled state that quantum bits (or “qubits”) require to function.

According to Intel, achieving a 49-qubit test chip is an important milestone because it will allow researchers to assess and improve error correction techniques and simulate computational problems.

Krzanich predicts that quantum computing will solve problems that today might take our best supercomputers months or years to resolve, such as drug development, financial modeling and climate forecasting. While quantum computing has the potential to solve problems conventional computers can’t handle, the field is still nascent.

Mike Mayberry, VP and managing director of Intel Labs weighed in on the progress of the efforts. “We expect it will be 5 to 7 years before the industry gets to tackling engineering-scale problems, and it will likely require 1 million or more qubits to achieve commercial relevance,” said Mayberry.

Krzanich said the need to scale to greater numbers of working qubits is why Intel, in addition to investing in superconducting qubits, is also researching another type called spin qubits in silicon. Spin qubits could have a scaling advantage because they are much smaller than superconducting qubits. Spin qubits resemble a single electron transistor, which is similar in many ways to conventional transistors and potentially able to be manufactured with comparable processes. In fact, Intel has already invented a spin qubit fabrication flow on its 300-mm process technology.

At CES, Krzanich also showcased Intel’s research into neuromorphic computing—a new computing paradigm inspired by how the brain works that could unlock exponential gains in performance and power efficiency for the future of artificial intelligence. Intel Labs has developed a neuromorphic research chip, code-named “Loihi,” which includes circuits that mimic the brain’s basic operation.

While the concepts seem futuristic and abstract, Intel is thinking of the technology in terms of real-world uses. Intel says Neuromorphic chips could ultimately be used anywhere real-world data needs to be processed in evolving real-time environments. For example, these chips could enable smarter security cameras and smart-city infrastructure designed for real-time communication with autonomous vehicles. In the first half of this year, Intel plans to share the Loihi test chip with leading university and research institutions while applying it to more complex data sets and problems.

For me to compare quantum and neuromorphic computing to USB is as about as apples and oranges as you can get. But, who knows? When the day comes when quantum or neuromorphic chips are in our everyday devices, maybe my comparison won’t seem far-fetched at all.

This appears in the February (331) issue of Circuit Cellar magazine

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

The Quest for Extreme Low Power

Input Voltage

–Jeff Child, Editor-in-Chief


Over the next couple years, power will clearly rank as a major design challenge for the myriad of edge devices deployed in Internet of Things (IoT) implementations. Such IoT devices are wireless units that need to be always on and connected. At the same time, they need low power consumption, while still being capable of doing the processing power needed to enable machine intelligence. The need for extreme low power in these devices goes beyond the need for long battery life. Instead the hope is for perpetually powered solutions providing uninterrupted operation—and, if possible, without any need for battery power. For their part, microcontroller vendors have been doing a lot in recent years within their own labs to craft extreme low power versions of their MCUs. But the appetite for low power at the IoT edge is practically endless.

Offering a fresh take on the topic, I recently spoke with Paul Washkewicz, vice president and co-founder of Eta Compute about the startup’s extreme low power technology for microcontrollers. The company claims to offer the lowest power MCU intellectual property (IP) available today, with voltages as low as 0.3 V. Eta Compute has developed and implemented a unique low power design methodology that delivers up to a 10x improvement in power efficiency. Its IP and custom designs operate over severe variations in conditions such as temperature, process, voltage and power supply variation. Eta Compute’s approach is a self-timed technology supporting dynamic voltage scaling (DVS) that is insensitive to process variations, inaccurate device models and path delay variations.

The technology has been implemented in a variety of chip functions. Among these are M0+ and M3 ARM cores scaling 0.3 V to 1.2 V operation with additional low voltage logic support functions such as real-time clocking (RTC), Advanced Encryption Standard (AES) and digital signal processing. The technology has also been implemented in an A-D converter sensor interface that consumes less than 5 µW. The company has also crafted an efficient power management device that supports dynamic voltage scaling down to 0.25 V with greater than 80% efficiency.

According to the company, Eta Compute’s technology can be implemented in any standard foundry process with no modifications to the process. This allows ease of adoption of any IP and is immune to delays and changes in process operations. Manufacturing is straightforward with the company’s IP able to port to technology nodes at any foundry. Last fall at ARM TechCon, David Baker, Ph.D. and Fellow at Eta Compute, did a presentation that included a demonstration of a small wireless sensor board that can operate perpetually on a small 1 square inch solar cell.

Attacking the problem from a different direction, another startup, Nikola Labs, is applying its special expertise in antenna design and advanced circuitry to build power harvesting into products ranging from wearables to sensors to battery-extending phone cases. Wi-Fi routers, mobile phones and other connected devices are continually emitting RF waves for communication. According to the company, radio wave power is strongest near the source—but devices transmit in all directions, saturating the surrounding area with stray waves. Nikola Labs’ high-performance, compact antennae capture this stray RF energy. Efficient electronics are then used to convert it into DC electricity that can be used to charge batteries or energize ultra-low power devices.

Nikola’s technology can derive usable energy from a wide band of frequencies, ranging from LTE (910 MHz) to Wi-Fi (2.4 GHz) and beyond (up to 6 GHz). Microwatts of power can be harvested in an active ambient RF area and this can rise to milliwatts for harvesters placed directly on transmitting sources. Nikola Labs has demonstrated energy harvesting from a common source of RF communication waves: an iPhone. Nikola engineers designed a case for iPhone 6 that captures waste RF transmissions, producing up to 30 mW of power to extend battery life by as much as 16% without impacting the phone’s ability to send and receive data.

Whether you address the challenge of extreme low power from the inside out or the outside in—or by advancing battery capabilities—there’s no doubt that the demand for such technologies will only grow within the coming years. With all that in mind, I look forward to covering developments on this topic in Circuit Cellar throughout 2018.

This appears in the January (330) issue of Circuit Cellar magazine

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