About Circuit Cellar Staff

Circuit Cellar's editorial team comprises professional engineers, technical editors, and digital media specialists. You can reach the Editorial Department at editorial@circuitcellar.com, @circuitcellar, and facebook.com/circuitcellar

IoT Security Solution for NXP MCUs

NXP Semiconductors has introduced its new A71CH Secure Element (SE), a trust anchor, ready-to-use security solution for next-generation IoT devices, such as edge nodes and gateways. Designed to secure peer-to-peer or cloud connections, the chip comes with the required credentials pre-injected for autonomous cloud onboarding and peer-to-peer authentication. The solution is a Root of Trust (RoT) at the silicon level, with security functionalities such as encrypted key storage, key generation and derivation to protect private information and credentials for mutual authentication.

Unique to the chip, is its ‘Plug & Trust” approach supporting easy integration of security and cloud onboarding. It does this using host libraries and a development kit compatible to different NXP microcontrollers (MCU and MPU) platforms such as Kinetis and i.MX. Also, example code and various application notes are available to streamline the design process.

Thanks to the collaboration with Data I/O, embedded systems developers further benefit from an easy personalization service on the A71CH for any quantities in addition to NXP’s trust provisioning service. As a result, the new security IC gives developers, even those with limited security expertise, freedom to innovate and deploy secure solutions.

The A71CH provides the following set of key features:

  • Protected access to credentials
  • Encrypted/authenticated interface to host processor
  • Certificate-based TLS set-up (NIST P-256)
  • TLS set-up using pre-shared secret (TLS-PSK)
  • Connectionless message authentication (HMAC)
  • ECC key generation & signature verification
  • Symmetric key derivation
  • Encrypted vault for product master secrets (key wrapping, derivation, locking)
  • Encrypted key injection


NXP Semiconductors | www.nxp.com

Target Boards for Renesas RX 32-bit MCUs

Renesas Electronics has announced three new Target Boards for the RX65N, RX130 and RX231 Microcontroller (MCU) Groups, each designed to help engineers jump start their home appliance, building and industrial automation designs. Priced below $30, the Target Boards lower the price threshold for engagement, allowing more system developers to make use of Renesas’ broad-based 32-bit RX MCU family.

The RX Target Boards provide an inexpensive entry point for embedded designers to evaluate, prototype and develop their products. Each board kit features an on-chip debugger tool that enables application design without requiring further tool investments. Through-hole pin headers provide access to all MCU signals pins, making it easy for users to interconnect to standard breadboards for fast prototyping.

The RX Target Board evaluation concept reuses the same PCB for all MCU variations. Since each member of the Renesas RX MCU Family has a common pin assignment, users experience a smooth transition between different RX Groups and RX Series using the same package version. In the case of the RX Target Boards, the widely used 100-pin LQFP package is on board.

The RX Target Boards offer everything designers need to start board and demo development, including a board circuit diagram and bill of materials, demo source code, user manual, and application notes. Additional Target Board variations will be released soon that will provide full coverage of the entire RX Family, from the low-power RX100 Series to the high-performance RX700 Series.

The RX65N MCU Group combines an enhanced RX CPU core architecture and 120 MHz operation to achieve processing performance of 4.34 CoreMark/MHz. The MCUs include an integrated Trusted Secure IP, enhanced, trusted flash functionality, and a human-machine interface (HMI) for industrial and network control systems operating at the edge of the Industrial Internet of Things (IIoT). The RX65N MCUs also include an embedded TFT controller and integrated 2D graphic accelerator with advanced features ideal for TFT displays designed into IIoT edge devices or system control applications. In addition, the RX65N MCUs include embedded communication-processing peripherals such as Ethernet, USB, CAN, SD host/slave interface and quad SPI.

The RX130 MCU Group provides 32 MHz operation with flash memory sizes up to 512 KB, and package sizes up to 100-pins to provide higher performance and compatibility with the RX231/RX230 Group of touch MCUs. The ultra-low power, low-cost RX130 Group adds higher responsiveness and functionality for touch-based applications requiring 3V or 5V system control and low power consumption. Featuring a new capacitive touch IP with improved sensitivity and robustness, and a comprehensive device evaluation environment, the new 32-bit RX130 MCUs are an ideal fit for devices designed with challenging, non-traditional touch materials, or required to operate in wet or dirty environments, such as a kitchen, bath or factory floor.

The RX Target Boards are available now through Renesas Electronics’ worldwide distributors with a recommended resale price below $30.

Renesas Electronics | www.renesas.com

In-Circuit Programming/Debugging Tool Supports PIC MCUs

Microchip Technology has introduced the MPLAB PICkit 4 In-Circuit Debugger. This low-cost PICkit 4 in-circuit programming and debugging development tool is meant to replace the popular PICkit 3 programmer by offering five times faster programming, a wider voltage range (1.2 V to 5 V), improved USB connectivity and more debugging interface options. In addition to supporting Microchip’s PIC microcontrollers (MCUs) and dsPIC Digital Signal Controllers (DSCs), the tool also supports debugging and programming for the CEC1702 family of hardware cryptography-enabled devices.

This low-cost programming and debugging solution is well suited for those designing in the 8-bit space, but it is also perfectly suited for 16- and 32-bit development due, in part, to its 300 MHz, high-performance ATSAME70Q21B microcontroller on board. The benefits of faster programming time are less waiting and better productivity during development. This is especially important when designing with 32-bit microcontrollers with larger memory capacities.

The PICkit 4 development tool enables debugging and programing using the graphical user interface of MPLAB X Integrated Development Environment (IDE). The tool connects to the design engineer’s computer using a Hi-Speed USB 2.0 interface and can be connected to the target via an 8-pin single inline header that supports advanced interfaces such as 4-wire JTAG and serial wire debug with streaming data gateway. It is also backward compatible for demo boards, headers and target systems using 2-wire JTAG and In-Circuit Serial Programming (ICSP) compatibility.

The new interfaces make this low-cost tool compatible with Microchip’s CEC1702 hardware cryptography-enabled devices. This low-power, but powerful, 32-bit MCU offers easy-to-use encryption, authentication and private and public key capabilities. CEC1702 users can now benefit from using Microchip’s development tools and support rather than being required to invest in third-party tools for programming and debugging. The MPLAB PICkit 4 (PG164140) development tool is available today for $47.95.

Microchip Technology | www.microchip.com

Advantech Joins Amazon’s AWS Partner Network

Advantech has joined the Amazon Web Services (AWS) Partner Network (APN) as Standard Technology Partner. As an APN Standard Technology Partner, Advantech provides a comprehensive range of wireless sensors and edge intelligence computers with complete IoT software solutions on AWS. Embedded developers can connect devices to a range of services offered on AWS in order to build scalable, global, and secure IoT applications, bringing computing capabilities to edge devices to several domain-focused vertical markets such as smart city, smart manufacturing and smart energy markets.

Advantech’s WISE-1520 Wireless Sensor Node (shown) is on Amazon FreeRTOS so that customers can easily and securely connect small devices and sensors directly to AWS or to powerful edge devices running AWS Greengrass, thus allowing them to collect data for their IoT applications. As the first wireless sensor node for the M2.COM family, the WISE-1520 comes with an Arm Cortex-M4 processor and low-power Wi-Fi connectivity, providing full compatibility with existing Wi-Fi infrastructure.

Advantech also offers the EIS-D210 Edge Intelligence Server, which is equipped with an Intel Celeron Processor N3350 and is compatible with AWS Greengrass core, thus ensuring that IoT devices can respond quickly to local events, interact with local resources, operate with intermittent connections, and minimize the cost of transmitting IoT data to the cloud. In addition to supporting field protocols(MQTT/OPC/Modbus) for sensor/device data acquisition, the EIS-D210 can be used with the Advantech IoT SDK for wireless sensor (Wi-Fi, LoRa, Zigbee) data integration. Furthermore, the EIS-D210 comes pre-integrated with Advantech’s WISE-PaaS/EdgeSense software solution, allowing users to incorporate sensor data aggregation, edge analytics, and cloud applications for fast and easy real-time operational intelligence. This EIS provides a range of connectivity options with excellent data handling and networking connection capabilities for various IoT applications.

Advantech’s EPC-R4760 IoT gateway, powered by the Qualcomm Arm Cortex-A53 APQ8016 platform, provides a unique combination of power and performance. The system also integrates abundant wireless solutions including Wi-Fi, BT, GPS, and extended 3G/LTE connectivity. For OS support, the EPC-R4760 can run Debian Linux, Yocto Linux, Ubuntu Linux, Android, and Windows 10 IoT Core, and it also supports AWS Greengrass, which gives users tremendous flexibility by allowing them to create AWS Lambda functions that can be validated on AWS and then be easily deployed to devices.

Advantech’s UTX-3117 IoT gateway is compatible with AWS Greengrass and Wind River Pulsar and, in addition to having a small footprint, it offers real-time security and supports various protocols that are needed to run IoT applications seamlessly across both AWS and on local devices or sensor nodes. In addition, by equipping it with a LoRa solution, the UTX-3117 offers a wide range of wireless connection options for controlling and collecting data from devices and sensor nodes. With these solutions, the UTX-3117 IoT gateway is ideal for smart energy applications. For example, it can collect solar panel and solar radiation data in real time via LoRa, and with AWS Greengrass built in, it can analyze the data and adjust the angle of solar panels to follow the sun and thereby maximize the effectiveness of the solar panels. AWS Greengrass can also be employed to analyze weather data so that the panels can be adjusted to prevent damage from elements such as strong wind or hail.

Advantech | www.advantech.com


STMicro Sensors Achieve Validation for Alibaba IoT OS

STMicroelectronics has announced the validation of its LSM6DSL 6-axis inertial sensor and LPS22HB pressure sensor for Alibaba IoT’s ecosystem, which enables users to create complete IoT (Internet-of-Things) nodes and gateway solutions with better time to market.

Announced last year, AliOS Things is a light-weight embedded operating system for Internet of Things, developed by Alibaba. The company recently announced the release of AliOS Things v1.2, which includes a sensor-based component called uData. The ST sensors that have passed the AliOS validation have been integrated in uData and the two companies are cooperating on the development of IoT systems that aim to improve end-user experiences.

The LSM6DSL (shown) is a system-in-package featuring a 3D digital accelerometer and a 3D digital gyroscope that operates at 0.65 mA in high-performance mode and enables always-on low-power features for an optimal motion experience for the consumer. High robustness to mechanical shock makes the LSM6DSL the preferred choice of system designers for the creation and manufacturing of reliable products. The LSM6DSL supports main OS requirements, offering real, virtual and batch sensors with 4 KB for dynamic data batching.

The LPS22HB is an ultra-compact piezoresistive absolute pressure sensor that functions as a digital output barometer. Dust-free and water-resistant by design, the sensor enables high accuracy and low-power operation. It is available in full-mold package with silicon cap and six 20µm holes guaranteeing sensor moisture resistance, relative accuracy of pressure measurement 0.1 mbar, and very low power consumption (12 µA in low-noise mode).

STMicroelectronics | www.st.com

BLE-Wi-Fi Module Solution Enables Compact IoT Gateways

Nordic Semiconductor announced that InnoComm Mobile Technology has employed Nordic’s nRF52832 Bluetooth Low Energy (Bluetooth LE) System-on-Chip (SoC) for its CM05 BLE-Wi-Fi Module. The CM05 is a compact module that combines Nordic’s Bluetooth LE solution with Wi-Fi and is designed to ease the development of IoT gateways. By combining these wireless technologies into one device, the developer eliminates the cost and complexity of working with separate Bluetooth LE and Wi-Fi modules.

The CM05-powered IoT gateway enables Bluetooth LE-equipped wireless products to connect to the Internet (via the Wi-Fi technology’s TCP/IP functionality), a key advantage for smart-home and -industry applications. The compact module enables developers to reduce gateway size, decrease production costsand speed time to market.

The Nordic SoC’s powerful 64 MHz, 32-bit Arm Cortex M4F processor provides ample processing power to both the Nordic’s S132 SoftDevice (a Bluetooth 5-certifed RF software protocol (“stack”)) and the Wi-Fi TCP/IP stack, eliminating the cost, space requirements, and power demands of an additional processor. In addition, the Nordic SoC’s unique software architecture, which cleanly separates the SoftDevice from the developer’s application code, eases the development process, and, when the gateway is deployed in the field, enables rapid, and trouble-free Over-the-Air Device Firmware Updates (OTA-DFU).

Nordic’s nRF52832 Bluetooth LE SoC supports Bluetooth 5, ANT and proprietary 2.4GHz RF protocol software and delivers up to 60 per cent more generic processing power, offering 10 times the Floating Point performance and twice the DSP performance compared to competing solutions. The SoC is supplied with the S132 SoftDevice for advanced Bluetooth LE applications. The S132 SoftDevice features Central, Peripheral, Broadcaster and Observer Bluetooth LE roles, supports up to twenty connections, and enables concurrent role operation.

Nordic Semiconductor | www.nordicsemi.com


Raspberry Pi IoT SBC Leverages Cypress Wi-Fi/Bluetooth SoC

Cypress Semiconductor has announced its Wi-Fi and Bluetooth combo solution is used on the new Raspberry Pi 3 Model B+ IoT single board computer. The Cypress CYW43455 single-chip combo provides high-performance 802.11ac Wi-Fi for faster Internet connections, advanced coexistence algorithms for simultaneous Bluetooth and Bluetooth Low Energy (BLE) operations such as audio and video streaming, and low-power BLE connections to smartphones, sensors and Bluetooth Mesh networks. The combo’s high-speed 802.11ac transmissions enable superior network performance, faster downloads and better range, as well as lower power consumption by quickly exploiting deep sleep modes. The Raspberry Pi 3 Model B+ board builds on the success of existing Raspberry Pi solutions using Cypress’ CYW43438 802.11n Wi-Fi and Bluetooth combo SoC.

Wi-Fi networks powered by 802.11ac simultaneously deliver low-latency and high-speed with secure device communication, making it the ideal wireless technology for connecting products directly to the cloud. The Raspberry Pi 3 Model B+ board with the highly-integrated Cypress CYW43455 combo SoC allows developers to quickly prototype industrial IoT systems and smart home products that leverage the benefits of 802.11ac.

The Raspberry Pi 3 Model B+ board features a 64-bit, quad-core processor running at 1.4 GHz, 1 GB RAM, full size HDMI and 4 standard USB ports, Gigabit Ethernet over USB2, Power over Ethernet capability, CSI camera connector and a DSI display connector. The platform’s resources, together with its 802.11ac wireless LAN and Bluetooth/BLE wireless connectivity, provide a compact solution for the intelligent edge of connected devices.

The Cypress CYW43455 SoC features a dual-band 2.4- and 5-GHz radio with 20-, 40- and 80-MHz channels with up to 433 Mbps performance. This fast 802.11ac throughput allows devices to get on and off of the network more quickly, preventing network congestion and prolonging battery life by letting devices spend more time in deep sleep modes. The SoC includes Linux open source Full Media Access Control (FMAC) driver support with enterprise and industrial features enabled, including security, roaming, voice and locationing.

Cypress’ CYW43455 SoC and other solutions support Bluetooth Mesh networks—low-cost, low-power mesh network of devices that can communicate with each other, and with smartphones, tablets and voice-controlled home assistants, via simple, secure and ubiquitous Bluetooth connectivity. Bluetooth Mesh enables battery-powered devices within the network to communicate with each other to easily provide coverage throughout even the largest homes, allowing a user to conveniently control all of the devices from the palm of their hand. The SoC is also supported in Cypress’ all-inclusive, turnkey Wireless Internet Connectivity for Embedded Devices (WICED) software development kit (SDK), which streamlines the integration of wireless technologies for IoT developers.

Cypress Semiconductor | www.cypress.com

Raspberry Pi Foundation | www.raspberrypi.org

NXP IoT Platform Links ARM/Linux Layerscape SoCs to Cloud

By Eric Brown

NXP’s “EdgeScale” suite of secure edge computing device management tools help deploy and manage Linux devices running on LSx QorIQ Layerscape SoCs, and connects them to cloud services.

NXP has added an EdgeScale suite of secure edge computing tools and services to its Linux-based Layerscape SDK for six of its networking oriented LSx QorIQ Layerscape SoCs. These include the quad-core, 1.6 GHz Cortex-A53 QorIQ LS1043A, which last year received Ubuntu Core support, as well as the octa-core, Cortex-A72 LS2088a (see farther below).

Simplified EdgeScale architecture
(click image to enlarge)
The cloud-based IoT suite is designed to remotely deploy, manage, and update edge computing devices built on Layerscape SoCs. EdgeScale bridges edge nodes, sensors, and other IoT devices to cloud frameworks, automating the provisioning of software and updates to remote embedded equipment. EdgeScale can be used to deploy container applications and firmware updates, as well as build containers and generate firmware.

The technology leverages the NXP Trust Architecture already built into Layerscape SoCs, which offers Hardware Root of Trust features. These include secure boot, secure key storage, manufacturing protection, hardware resource isolation, and runtime tamper detection.

The EdgeScale suite provides three levels of management: a “point-and-click” dashboard, a Command-Line-Interface (CLI), and the RESTful API, which enables “integration with any cloud computing framework,” as well as greater UI customization. The platform supports Ubuntu, Yocto, OpenWrt, or “any custom Linux distribution.”

Detailed EdgeScale architecture (left) and feature list
(click images to enlarge)
EdgeScale supports cloud frameworks including Amazon’s AWS Greengrass, Alibaba’s Aliyun, Google Cloud, and Microsoft’s Azure IoT Edge. The latter was part of a separate announcement released in conjunction with the EdgeScale release that said that all Layerscape SoCs were being enabled with “secure execution for Azure IoT Edge computing running networking, data analytics, and compute-intensive machine learning applications.”

A year ago, NXP announced a Modular IoT Framework, which was described as a set of pre-integrated NXP hardware and software for IoT, letting customers mix and match technologies with greater assurance of interoperability. When asked how this was related to EdgeScale, Sam Fuller, head of system solutions for NXP’s digital networking group, replied: “EdgeScale is designed to manage higher level software that could have a role of processing the data and managing the communication to/from devices built from the Modular IoT Framework.”

LS102A block diagram
(click image to enlarge)
The EdgeScale suite supports the following QorIQ Layerscape processors:

  • LS102A — 80 0MHz single-core, Cortex-A53 with 1 W power consumption found on F&S’ efus A53LS module
  • LS1028A — dual-core ARMv8 with Time-Sensitive Networking (TSN)
  • LS1043A — 1.6 GHz quad-core, Cortex-A53 with 1 0GbE support, found on the QorIQ LS1043A 10G Residential Gateway Reference Design and the X-ES XPedite6401 XMC/PrPMC mezzanine module
  • LS1046A — quad-core, Cortex-A72 with dual 10 GbE support (also available in dual-core LS1026A model)
  • LS1088a — 1.5 GHz octa-core, Cortex-A53 with dual 10 GbE support, which is also supported on the XPedite6401
  • LS2088a — 2.0 GHz octa-core, Cortex-A72 with 128-bit NEON-based SIMD engine for each core, plus a 10GbE XAUI Fat Pipe interface or 4x 10GBASE-KR — found on X-ES XPedite6370 SBC.

Further information

NXP’s EdgeScale will be available by the end of the month. More information may be found on its EdgeScale product page.

NXP Semiconductors | www.nxp.com

This article originally appeared on LinuxGizmos.com on March 16.

April (issue #333) Circuit Cellar Article Materials

Click here for the Circuit Cellar article code archive

p. 6: Build a Marginal Oscillator Proximity Switch: Detection Duty, By Dev Gualtieri

Texas Instruments | www.ti.com

p 10: Obsolescence-Proof Your UI (Part 1): Web Server Strategy, By Steve Hendrix

Jeff Bachiochi, “Serving Up HTML”, Circuit Cellar, June 2016 / July 2016
Microchip, “TCPIP Stack Help.chm”, provided with the downloadable TCP/IP stack
Steve Hendrix, “Personal Solar Power Setup”, Circuit Cellar, July 2014 / August 2014

HTML Elements: https://developer.mozilla.org/en-US/docs/Web/HTML/Element
HPGL tools: http://www.ke5fx.com/gpib/readme.htm
Announcement monitor: www.logview4net.com

Angry IP Scanner | www.angryip.org
Digi-Key | www.digikey.com
Microchip | www.microchip.com

p. 18: Color Recognition and Segmentation in Real Time: FPGA-Based Approach, By Claire Chen and Mark Zhao

[1] W. Qadeer, et al., “Convolution Engine: Balancing Efficiency & Flexibility in Specialized Computing,” Int’l Symposium on Computer Architecture, June 2013
[2] J. Cabral, S. de Araujo, “An Intelligent Vision System for Detecting Defects in Glass Products for Packaging and Domestic Use,” Int’l Journal of Advanced Manufacturing Technology, March 2015
[3] R. S. Sebeenian, M. E. Paramasivam, P. M. Dinesh, “Computer Vison Based Defect Detection and Identification in Handloom Silk Fabrics,” Int’l Journal of Computer Applications, March 2012
[4] D. Sun, “Surface Potato Defects”, Computer Vision Technology for Food Quality Evaluation, April 2016 (Book)
[5] Terasic Technologies Inc., “Introduction of the DE1-SoC Board,” DE1-SoC User Manual, 2003-2014
[6] Altera Corp (now Intel PSG)– University Program, Introduction to the Altera Qsys System Integration Tool, October 2012
[7] Intel, Avalon Interface Specifications, May 2017
[8] Altera Corp. (now Intel PSG) – University Program, Video IP Cores for Altera DE-Series Boards, August 2012
[9] Altera Corp. (now Intel PSG) – University Program, External Bus to Avalon Bridge, May 2013
[10] Intel Corp. – FPGA University Program, Video IP Cores for Intel DE-Series Boards, November 2016
[11] H. Chu, S. Ye, Q. Guo and X. Liu, “Object Tracking Algorithm Based on Camshift Algorithm Combinating with Difference in Frame,” 2007 IEEE International Conference on Automation and Logistics, Jinan, 2007, pp. 51-55
[12] Parallax Inc., “Parallax Continuous Rotation Servo,” October 2011

Intel PSG (formerly Altera) | www.altera.com
Parallax | www.parallax.com

 p. 26 : Temperature Coefficient of Resistance Explored: Precision and Performance, By Molly Bakewell Chamberlin for Vishay Precision Group

VPG Foil Resistors | www.vpgfoilresistors.com
Embassy Global LLC | www.embassyglobal.com

p.32: IoT: From Gateway to Cloud: Starting Up, Scaling Up, By Jeff Child

Atmosphere IoT | www.atmosphereiot.com
Eurotech | www.eurotech.com
Kontron | www.kontron.com
Mentor Graphics | www.mentor.com
Microchip | www.microchip.com
NXP Semiconductors | www.nxp.com
Renesas Electronics | www.renesas.com
STMicroelectronics | www.st.com
Texas Instruments | www.ti.com
Wind River | www.windriver.com

p.38: Displays Fit Diverse Embedded System Needs: Many Sizes and Solutions,
By Jeff Child

4D Systems | www.4dsystems.com.au
Axiomtek | www.axiomtek.com
Cincoze | www.cincoze.com
Jon Peddie Research | www.jonpeddie.com
Newhaven Display | www.newhavendisplay.com
Pervasive Displays | www.pervasivedisplays.com
WinSystems | www.winsystems.com

p.50: Internet of Things Security (Part 2): Side-Channel Attacks, By Bob Japenga

Colin O’Flynn has written some great articles on some side-channel attacks in Circuit Cellar:
August 2016  “Breaking Unbreakable Cryptography with Power Analysis Attacks”
April 2017 “Introduction to Timing and Power Analysis Attacks”
June 2017 “Breaking a Password with Power Analysis Attacks”
August 2017  “Power Analysis of a Software DES Encryption Routine”
November 2017 “Power Analysis Attack on RSA”
January 2018 “Five Fault Injection Attacks.”

Kocher, Jaffee, and Jun, “Differential Power Analysis;”

VIDEO: Colin O’Flynn, “Timing Attack on PIN-Protected Hard Drive”:

P. C. Kocher, “Timing Attacks on Implementations of Diffie-Hellman, RSA, DSS, and Other Systems”

Hutter and Schmidt, “The Temperature Side-Channel and Heating Fault Attacks,” 2014

K. Gandolfi, D. Naccache, C. Paar, K. G, C. Mourtel, and F. Olivier, “Electromagnetic analysis: Concrete results,” 2001.

I recommend this Homeland Security Agency’s web site highly. https://ics-cert.us-cert.gov/

Microchip Technology datasheet http://www.atmel.com/Images/Atmel-11267-32-bit-Cortex-A5-Microcontroller-SAMA5D2_Datasheet.pdf

p.54: Component Tolerance: Accuracy Unmasked, By Robert Lacoste

E-series of preferred numbers: https://en.wikipedia.org/wiki/E-series_of_preferred_numbers

“Precision Matched Resistors Automatically Improve Differential  Amplifier CMRR – Here’s How” Design Note 1023 by Kris Lokere, Tyler Hutchison, Greg Zimmer, Linear Technology

Drift Calculation for Thin Film Resistors: https://www.vishay.com/docs/28809/driftcalculation.pdf

“Combining Multiple Resistors to Improve Tolerance” by Paulo Renato

Murphy’s law web site: http://www.murphys-laws.com

Analog Devices | www.analog.com
Linear Technology | www.linear.com
Tektronix | www.tek.com
Vishay | www.vishay.com

p.60: Design of Complex Systems: Safety Standards, By George Novacek

[1] SAE ARP4754A Certification Considerations for Highly Integrated or Complex Aircraft Systems
[2] SAE document downloading site for ARP4754A: http://standards.sae.org/arp4754a/

SAE International | www.sae.org

p. 64 : Texting and IoT Embedded Devices (Part 2): A Messaging Mission,
By Jeff Bachiochi

[1] Video provides great explanation of NAT (Private vs Public) Network IP Translation:

Espressif Systems | www.espressif.com
FTDI Chip | www.ftdichip.com

Tuesday’s Newsletter: IoT Tech Focus

Coming to your inbox tomorrow: Circuit Cellar’s IoT Technology Focus newsletter. Tomorrow’s newsletter covers what’s happening with Internet-of-Things (IoT) technology–-from devices to gateway networks to cloud architectures. This newsletter tackles news and trends about the products and technologies needed to build IoT implementations and devices.

Bonus: 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 IoT Technology Focus newsletter issue tomorrow.

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

Our weekly Circuit Cellar Newsletter will switch its theme each week, so look for these in upcoming weeks:

Embedded Boards.(3/27 Wednesday) The focus here is on both standard and non-standard embedded computer boards that ease prototyping efforts and let you smoothly scale up to production volumes.

Analog & Power. (4/3) 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 (4/10) 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.

Software Aids STM32 MCU System Development

STMicroelectronics has extended its STM32 software ecosystem with a Sigfox package that simplifies development and gives extra flexibility to connect Internet-of-Things (IoT) devices to long-range, low-power wireless networks. The new X-CUBE-SFOX package is ready to use with ST’s B-L072Z-LRWAN1 Discovery Kit, which is already LoRa enabled through I-CUBE-LRWAN embedded software. Developers can now work with either of these established Low-Power Wide Area Network (LPWAN) technologies on the same hardware, and create products that can use the two protocols individually or alternatively.

The Discovery Kit features the Murata CMWX1ZZABZ-091 module powered by an STM32L072 microcontroller, a sub-GHz radio transceiver SX1276 from Semtech, and is expandable via Arduino headers to add sensors or other IoT-device functions and capabilities. X-CUBE-SFOX contains a complete set of Sigfox libraries and application examples for the STM32L0, and can be ported to other microcontrollers in the STM32 family.

With over 700 STM32 variants, from ultra-low-power to high-performance lines, developers can leverage unrivaled flexibility to optimize the performance and features of IoT devices that take advantage of Sigfox services including basic connectivity, radio recognition, and GPS-free location. The software’s low memory footprint and efficient CPU utilization minimize demand for system resources, helping to lower bill-of-materials (BOM) costs and power consumption.

The X-CUBE-SFOX software can be downloaded free of charge from www.st.com/x-cube-sfox. The B-L072Z-LRWAN1 Discovery Kit is available now, priced $46.50.

STMicroelectronics | www.st.com

Power Management ICs Reduce Charge Times

Texas Instruments (TI) has introduced several new power management chips that enable designers to boost efficiency and shrink power supply and charger solution sizes for personal electronics and handheld industrial equipment. Operating at up to 1 MHz, TI’s new chipset combines the UCC28780 active clamp flyback controller and the UCC24612 synchronous rectifier controller to help cut the size of power supplies in AC/DC adapters and USB Power Delivery chargers in half. For battery-powered electronics that need maximum charging efficiency in a small solution size, TI also offers the bq25910. It is a 6-A three-level buck battery charger enables up to a 60% smaller-solution footprint in smartphones, tablets and electronic point-of-sale devices.

Designed to work with both gallium nitride (GaN) and silicon (Si) FETs, the UCC28780’s advanced and adaptive features enable the active clamp flyback topology to meet modern efficiency standards. With multimode control that changes the operation based on input and output conditions, pairing the UCC28780 with the UCC24612 can achieve and maintain high efficiency at full and light loads.

The chipset delivers efficient operation at up to 1 MHz, enabling a size reduction of 50% and higher power density than solutions today. Multimode control enables efficiency up to 95 percent at full loads and standby power of less than 40 mW, exceeding Code of Conduct (CoC) Tier 2 and U.S. Department of Energy (DoE) Level VI efficiency standards. For designs above 75 W, engineers can also pair the chipset with a new six-pin power-factor correction (PFC) controller, the UCC28056, which is optimized for light-load efficiency and low standby power consumption to achieve compliance with mandatory International Electrotechnical Commission (IEC)-61000-3-2 AC current harmonic limit regulations. Using features such as adaptive zero voltage switching (ZVS) control, engineers can easily design their systems with a combination of resistor settings and controller auto-tuning.

Leveraging an innovative three-level power-conversion technology, the bq25910 enables up to 50 percent faster charging compared to conventional architectures by dramatically reducing thermal loss. With integrated MOFSETs and lossless current sensing, the bq25910 reduces printed circuit board (PCB) space and allows designers to use small 0.33-µH inductors, saving even more space. The bq25910 enables 95 percent charging efficiency, which could take a standard smartphone battery from empty to 70 percent charged in less than 30 minutes. A differential battery-voltage sense line enables fast charging by bypassing parasitic resistance in the PCB for more accurate voltage measurements, even if the battery is placed away from the charger in the system.

Texas Instruments | www.ti.com


A Tribute to Technology Pioneer Bob Lally

Bob Lally, founder of PCB Piezotronics, and a co-founder of the original Kistler Instrument Company, passed away recently at the age of 93. In addition to Bob’s legendary technical contributions, he will be remembered for his brave military service during World War II and post-retirement work in STEM.

Throughout his career, Bob’s R&D work was awarded multiple U.S. patents, including for the modally-tuned piezoelectric impact hammer, pendulum hammer calibrator, and gravimetric calibrator. He was most renowned, however, for his successful commercialization of a two-wire accelerometer with built-in electronics, known as integrated circuit piezoelectric, or ICP, which made the sensors lower cost, easier to use and more compatible with industrial environments.

For more on Bob Lally’s story read “Celebrating the Life of a True Industry Pioneer” on Sensors Online.

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.

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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.



Texting and IoT Embedded Devices (Part 1)

Fun with the ESP8266 SoC

Can texting be leveraged for use in IoT Wi-Fi devices? Jeff has been using Wi-Fi widgets for a lot of IoT projects lately. This month Jeff lays the groundwork for describing a project that will involve texting. He starts off with a look at Espressif System’s ESP8266EX SoC.

By Jeff Bachiochi

Believe it or not, texting while driving as of this writing is still legal in a few states. About 10% of all motor vehicles deaths in the US can be traced back to distracted drivers. Granted that includes any distraction—however cell phone distraction has quickly become a serious issue. While hazards exist for any technology, common sense should tell you this is a dangerous act.

When the technology is used correctly, texting can deliver essential information quickly—without requiring both (or many) parties to be active at the same time. This allows you to make better use of your time. I still use email for much of my correspondence, however it’s great to be able to send your spouse a text to add milk to the grocery list—after they’ve already left for the store! And even though I chuckle when I see two people sitting next to each other texting, it is a sad commentary on emerging lifestyles.

I’ve been using Wi-Fi widgets for a lot of IoT projects lately. The cost to enter the fray is low, and with free tools it’s easy to get started. This month’s article is a about a project that will involve text, even though that may not be apparent at first. Let’s start off slowly, laying the groundwork for those who have been thinking about building this kind of project. We’ll then quickly build from this foundation into crafting a useful gadget.

A Look at the ESP8266EX

The innovative team of chip-design specialists, software/firmware developers and marketers at Espressif System developed and manufactures the ESP8266EX system-on-chip (SoC). This 32-bit processor runs at 80 MHz and embeds 2.4 GHz Wi-Fi functionality—802.11 b/g/n, supporting WPA/WPA2—as well as the normal gamut of general-purpose I/O and peripherals. It has a 64 KB boot ROM, 64 KB instruction RAM and 96 KB data RAM. Their WROOM module integrates the ESP8266 with a serial EEPROM and an RF front end with a PCB antenna for a complete IoT interface.

Anyone who has ever used a dial-up modem is most likely familiar with the term AT command set. The Hayes command set is a specific command language originally developed in 1981 by Dennis Hayes for the Hayes 300 baud Smartmodem. Each command in the set begins with the letters AT+ followed by a command word used for high-level control of internal functions. For the modem these enabled tasks like dialing the phone or sending data. As an application for the WROOM, an AT command set seemed like a perfect match. This allows an embedded designer to use the device to achieve a goal without ever having to “get their hands dirty.”

This photo shows the ESP-01 and ESP-07 modules along with the FTDI 232 USB-to-serial converter used for programming either module.

I first learned of the ESP8266 years ago and purchased the ESP-01 on eBay. It was around $5 at the time (Photo 1). I used it along with the MEGA 2560—my favorite Arduino module because of its high number of I/Os and multiple hardware UARTs. With the ESP-01 connected to a serial port on an Arduino, an application could directly talk with the ESP-01 and get the Arduino connected to your LAN. From this point, the world is under your control thanks to the AT Wi-Fi and TCP commands.

The ESP8266 literature states the Wi-Fi stack only requires about 20% of the processing power. Meanwhile, 80% is still available for user application programming and development.
So why not eliminate the Arduino’s Atmel processor altogether and put your Arduino code right in the 8266? Espressif Systems has an SDK and while it provides a development and programming environment, the Arduino IDE is comfortable for many. And it offers the installation of third-party platform packages using the Boards Manager. That means you can add support for the ESP8266EX and use much of the code you’ve already written.

Using the ESP-01

Since the ESP-01 has only 8 pins, adding the necessary hardware is pretty simple. This low power device runs on 2.5 V to 3.6 V, so you must make appropriate level corrections if you wish to use it with 5 V devices like Arduino boards. …

Read the full article in the March 332 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.