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

USB Data Acq System Features Simple Expansion

DATAQ Instruments has announced the release of its model DI-2108-P USB data acquisition (DAQ) system with 16-bit ADC resolution, programmable gain and ChannelStretch technology. The model DI-2108-P provides eight analog input channels each with 2.5-, 5- and 10-volt unipolar and bi-polar programmable measurement ranges. DATAQ Instruments di2108-product-photo-press-releaseThe DI-2108-P also provides 7 digital ports, each configurable as an input or a switch. Two ports can be programmed as counter and frequency measurement inputs. The instrument’s maximum sampling throughput rate is 160 kHz.

The ChannelStretch feature of the DI-2108-P makes channel expansion as easy as adding another device. Plug a second device into a computer and double the channel count of both analog and digital channels. Using USB hubs, plug up to sixteen devices into a single PC for a maximum count of 128 analog and 112 digital channels. And all of them are acquired synchronously at a maximum sample throughput rate of at least 480 kHz. DI-2108-P software support includes ready-to run WinDaq data acquisition software, .Net class, ActiveX controls and a fully documented communication protocol to deploy the instrument on any platform. The unit is priced at $349.

DATAQ Instruments | www.dataq.com

8-bit Microcontroller Features Compact 8-Pin Package

STMicroelectronics has introduced its new 8-bit STM8S001 microcontroller (MCU) in an economical SO-8 package. The STM8S001 has I2C, UART, and SPI interfaces, giving unusually versatile connectivity options. With a generous 8KB Flash memory, 1 KB RAM, 128-byte EEPROM, and 3-channel 10-bit ADC also on-chip, it delivers key features of ST’s STM8S003 MCU in a space-saving, low-pin-count device. Additional features include five en.STM8S_MCU_8_pin_package_N3970S_bigGPIOs, one 8-bit and two 16-bit timers, and an internal RC oscillator that allows flexible clock control from 128 kHz to 16 MHz. There is also a Single-Wire Interface Module (SWIM) for programming and debugging.

Fully specified from -40°C to 125°C and featuring the modern and efficient STM8 core operating at 16 MHz, the STM8S001 is well suited for industrial devices like smart sensors and lighting controls, as well as consumer products such as toys, small appliances, personal electronics, PC peripherals, battery chargers, and many others. The STM8S001 in 8-pin SO-8 is in production now, priced from $0.20 for orders of 1,000 pieces. A Discovery kit will be available in Q4 2017.

STMicroelectronics | www.st.com

Nissan Chooses Renesas Chips for Automatic-Parking Gear

Renesas Electronics has announced that its R-Car system-on-chip (SoC) for car infotainment and advanced driving assistant systems (ADAS) as well as its RH850 automotive control microcontroller have been adopted by Nissan for the ProPILOT Park, a full-fledged automated-parking system, of its new LEAF, Nissan’s new 100 percent electric vehicle.

The R-Car SoC adopted in the ProPILOT Park of the new Nissan LEAF recognizes spaces adequate for parking, verifies that there are no obstacles in the way, and handles 20170906-soc-mcu-automated-parkingthe role of issuing control commands for acceleration, braking, steering and shifting. The R-Car SoC includes Renesas’ exclusive parallel image processor (IMP) dedicated for image processing. The IMP takes the high-resolution images from the latest automotive CMOS digital cameras and performs high-speed, low-power signal processing. The RH850 MCU accepts the chassis control commands from the R-Car SoC and transmits these commands to the various electronic control units (ECUs) used. This enables the Nissan LEAF’s ProPILOT Park to achieve safe and reliable parking operation.

Based on the newly-launched Renesas autonomy, a new advanced driving assistance systems (ADAS) and automated driving platform, Renesas enables a safe, secure, and convenient driving experience by providing innovative solutions for next-generation car.

Renesas Electronics | www.renesas.com

Don’t Miss Our Newsletter: IoT Technology Focus

In tomorrow’s IoT Technology Focus newsletter you’ll get news and trends about the products and technologies needed to build IoT implementations and devices. image002

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

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

Embedded Boards. This content looks at embedded board-level computers. The focus here is on modules—Arduino, Raspberry Pi, COM Express, and other small-form-factor —that ease prototyping efforts and let you smoothly scale up production volumes.

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.

Wi-Fi MCU Platform Update Targets Smart Home

Cypress Semiconductor has announced an updated version of its turnkey development platform for the IoT that simplifies the integration of wireless connectivity into smart home applications. The Wireless Internet Connectivity for Embedded Devices (WICED) Studio platform now adds iCloud remote access support for Wi-Fi-based accessories that support Apple HomeKit. Developers can leverage iCloud support in the WICED software Cypress WICED IoT Development Kit_0development kit (SDK) and Cypress’ CYW43907 Wi-Fi MCU to create hub-independent platforms that connect directly to Siri voice control and the Apple Home app remotely. Developers can access the WICED Studio platform, ecosystem and community at www.cypress.com/wicedcommunity.

Using Cypress’ WICED development platform and ultra-low power CYW20719 Bluetooth/BLE MCU, developers can integrate HomeKit support into products such as smart lighting devices, leverage Siri voice control and connect to the Apple Home app seamlessly. WICED Studio provides a single development environment for multiple wireless technologies, including Cypress’ world-class Wi-Fi, Bluetooth and combo solutions, with an easy-to-use application programming interface in the world’s most integrated and interoperable wireless SDK. The kit includes broadly deployed and rigorously tested Wi-Fi and Bluetooth protocol stacks, and it offers simplified application programming interfaces that free developers from needing to learn about complex wireless technologies. The SDK also supports Cypress’ high-performance 802.11ac Wi-Fi solutions that use high-speed transmissions to enable IoT devices with faster downloads and better range, as well as lower power consumption by quickly exploiting deep sleep modes.

The Cypress CYW43907 SoC integrates dual-band IEEE 802.11b/g/n Wi-Fi with a 320-MHz ARM Cortex-R4 RISC processor and 2 MB of SRAM to run applications and manage IoT protocols. The SoC’s power management unit simplifies power topologies and optimizing energy consumption. The WICED SDK provides code examples, tools and development support for the CYW43907.

 WICED Studio IoT Development Platform

The WICED platform supports a broad range of other popular cloud services and eliminates the need for developers to implement the various protocols to connect to them, reducing development time and costs. The WICED Studio SDK enables cloud connectivity in minutes with its robust libraries that uniquely integrate popular cloud services such as iCloud, Amazon Web Services, IBM Bluemix, Alibaba Cloud, and Microsoft Azure, along with services from private cloud partners and China’s Weibo social media platform.

In line with the IoT trend toward dual-mode connectivity, the kit supports Cypress’ Wi-Fi and Bluetooth combination solutions and its low-power Bluetooth and Bluetooth Low Energy (BLE) combination solutions. The SDK features a single installer package for multiple wireless technologies with an Eclipse-based Integrated Development Environment (IDE) that runs on multiple operating systems, including Windows, MacOS and Linux.

Cypress’ WICED Studio connectivity suite is microcontroller (MCU)-agnostic and provides ready support for a variety of third-party MCUs to address the needs of complex IoT applications. The platform also enables cost efficient solutions for simple IoT applications by integrating MCU functionality into the connectivity device. Wi-Fi and Bluetooth protocol stacks can run transparently on a host MCU or in embedded mode, allowing for flexible platform architectures with common firmware.

Cypress Semiconductor | www.cypress.com

Buck Converter Extends Battery Life of USB Type-C Gear

Maxim Integrated Products has announced the MAX77756, a 24 V, 500 mA, low quiescent current (IQ) buck converter. The product targets developers of multi-cell, USB Type-C products in need high current, dual inputs and I2C support. USB Type-C products must generate an always-on 3.3 V rail to detect USB insertions. Products utilizing the Power Delivery (PD) voltage range (5 V to 20 V) can generate an always-on (1.8 V /3.3 V /5.0 V) digital supply MAX77756_EVKit_imagerail for the port controller using the MAX77756 step-down converter. In addition, the MAX77756 has a 2 0 μA quiescent current that extends battery life by reducing idle power consumption. To simplify the system design, the MAX77756 has a dual input ideal diode ORing circuit that allows the chip to power from the external USB source if the battery is empty.

Multi-cell battery-operated devices—such as ultrabooks, laptops, tablets, drones and home automation appliances—can easily evolve to Type-C with PD using the flexible MAX77756 power supply. The MAX77756 has a unique combination of wide input voltage range, low quiescent current, higher current load, dual input, and I2C for flexibility and programmability. There is also a default power mode if customers do not want to use the I2C bus. The MAX77756 is a robust IC with short-circuit and thermal protection, 8ms internal soft-start to minimize inrush current, proven current-mode control architecture, and up to 26V input voltage standoff.

Key Advantages

  • Low quiescent current: 1.5 μA Buck and 20 μA MUX for always-on operation
  • High efficiency: Up to 92% with integrated power MUX
  • Small solution size: 2.33mm x 1.42mm 15-bump WLP; no external Schottky array needed
  • Wide input voltage: Operates on full VBUS range (5 V – 20 V) and VBATT (2S, 3S, 4S Li+)

MAX77756 is available from stock and priced at $0.65 (10,000+)..An evaluation board MAX77756EVKIT# (see photo) is available from stock and priced at $70

Maxim Integrated Products | www.maximintegrated.com

October Circuit Cellar: A Sneak Preview

The October issue of Circuit Cellar magazine is on the launch pad, ready to deliver a selection of excellent embedded electronics articles covering trends, technology and design.

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Here’s a sneak preview of October Circuit Cellar:

TECHNOLOGY FOR DRONES / ROBOTIC HAND

Commercial Drone Design Solutions Take Flight: Chips, Boards and Platforms
The control, camera and comms electronics inside today’s drones have to pack in an ambitious amount of functionality. Circuit Cellar Chief Editor Jeff Child explores the latest Oct 327 Coverand greatest chip and module solutions serving today’s commercial and consumer drone designs.

Building a Robot Hand: With Servos and Electromyography
Learn how three Cornell University students developed a robotic hand. The system captures impulses generated by muscle contractions and then filters and feeds those signals to a microcontroller which controls finger movement.

 

CAN’T STOP THE SIGNAL

Signal Chain Tech Pushes Bandwidth Barriers: ADCs, FPGAs and DACs
FPGAs and D-A converters are key  technologies making up a signal chain. Here, Circuit Cellar Chief Editor Jeff Child steps through the state-of-the-art options available for crafting efficient, highly-integrated signal-centric systems.

Antenna Performance Measurement Made Easy: Covering the Basics
If you’re doing any kind of wireless communications design, chances are you’re including an antenna. Columnist Robert Lacoste shows how the task of measuring an antenna’s performance is less costly and exotic than you’d think.

MONITORING GEAR WITH MICROCONTROLLER BRAINS

Gas Monitoring and Sensing (Part 1): Fun with Fragrant Analysis
Columnist Jeff Bachiochi covers the background issues surrounding gas monitoring and sensing. Then he describes how he uses sensors, A/D conversion and Arduino technologies to do oxygen measurement.

Logger Device Tracks Amp Hours (Part 1): Measuring Home Electricity
Setting out to monitor and log electricity usage in his house, Bill Wachsmann built an amp-hour logger using a microcontroller and a clamp on ammeter.

KEEPING THE LEGACY ALIVE

Emulating Legacy Interfaces: Do it with Microcontrollers
There’s a number of important legacy interface technologies—like ISA and PCI—that are no longer supported by the mainstream computing industry. In his article Wolfgang Matthes examines ways to use microcontrollers  to emulate the bus signals of legacy interconnect schemes.

Building a Retro TV Remote : PIC MCU-Based Design
Dev Gualtieri embarks on building a retro-style TV remote, based on a Microchip PIC microcontroller. He outlines the phototransistor, battery and software designs he made along the way.

AND MORE FROM OUR EXPERT COLUMNISTS:

Get in the Loop on Positive Feedback: New Value in an Old Concept
Positive feedback loops are an important element of modern circuitry such as crystal oscillators, PLLs and other devices. Here, George Novacek goes deep into the math and circuit analysis of positive feedback and how it’s used in electronics.

Build an Embedded Systems Consulting Company (Part 6): Trade-Offs of Fixed-Price Contracts
Continuing his “Building an Embedded Systems Consulting Company” article series, this month Bob Japenga explores the nature of contracts and how fixed price contracts can be an effective, albeit dangerous tool in marketing.

Power Modules Offer Day/Night Functionality

Saelig has introduced the patented Sol Chip Pak (SCP-R2801) Power Modules which offer day/night non-stop functionality by combining state-of-the-art solar cells, a rechargeable battery and advanced power management circuitry. These power modules include all the components that are required to harvest energy from ambient light, charge a built-in Saelig scp-power-modulerechargeable battery, and deliver a stable voltage to a load. Sol Chip’s patented technology integrates solar energy conversion with very large-scale integration (VLSI) techniques to produce unique ambient light harvesting devices that can even extract energy from office lighting to provide 24/7power. These versatile boards, based on Sol Chip’s unique Saturn cells, provide power even in office light conditions.

The output voltage of these “everlasting solar batteries” is regulated to 3.6 V, but other voltages are available by request to suit alternate applications. Versions are available with 1, 2, 3, or 6 Saturn solar cells depending on the power needs. The 6-cell version provides an average output current of up to 750 µA from the integrated solar cells, with up to 1.5 A peak current. The capacity of the 3.6 V on-board rechargeable batteries in the series is 190 mAh to 1,100 mAh.

Saelig | www.saelig.com

SBC is Drop-In Replacement for Raspberry Pi 3 Model B

A Kickstarter project by the Libre Computer Project, code name Le Potato, is designed as a drop in hardware replacement for the Raspberry Pi 3 Model B and offers faster performance, more memory, lower power, higher I/O throughput, 4K capabilities, open market components, improved media acceleration, removal of the vendor locked-in interfaces and Android 7.1 support. This platform uses the latest technologies and is built upon proven long term available chips. It is supported by upstream Linux and has a downstream development package based on Linux 4.9 LTS that offers ready-to-go 4K media decoding, 3D acceleration and more. dbedba7f6223adc66b712249125e66cb_original

It can be used to tinker with electronics, teach programming, build media centers, create digital signage solutions, play retro games, establish bi-directional video, and unlock imaginations. It is available in 1 GB and 2 GB configurations.

For connectivity I/O the board provides:

  • HDMI 2.0
  • 4 USB 2.0 Type A
  • RJ45 100Mb Fast Ethernet
  • CVBS
  • Infrared Receiver
  • S/PDIF Header
  • UART Header
  • I2S + ADC Header
  • 40 Pin Header for PWM, I2C, I2S, SPI, GPIO
  • eMMC Daughter Board Connector
  • MicroSD Card Slot with UHS Support

The board features these improvements over Raspberry Pi 3 Model B:

  • 50% Faster CPU and GPU
  • Double RAM Available
  • Lower Power Consumption
  • Better Android 7.1 and Kodi Support
  • Much Better Hardware Accelerated Codec Support
  • 4K UHD with HDR over HDMI 2.0
  • MicroSD Card UHS Support
  • eMMC Daughter Board Support
  • IR Receiver
  • ADC + I2S Headers
  • Non-Shared Bandwidth for LAN and USB

Libre Computer Project | https://libre.computer/

Analog Devices Collaborates on IoT Farm-to-Fork Project

Analog Devices has announced a collaboration with The Cornucopia Project and ripe.io to explore the local food supply chain and use this work as a vehicle for educating students at ConVal Regional High School in Peterborough, NH, and local farmers on 21st century agriculture skills. The initiative instructs student farmers how to use Internet of Things and blockchain technologies to track the conditions and movement of produce from “Farm to Fork” to make decisions that improve quality, yields, and profitability. Together with the Cornucopia Project, the endeavor is funded by Analog Devices and ripe.io, with both companies also providing technical training.

Analog Devices Smart Agriculture Manager Erick Olsen (center) and Senior Engineer Rob O'Reilly are pictured alongside ConVal Regional High School Farm to Fork Fellows viewing tomatoes grown with the company's crop monitoring solution. (Photo: Business Wire)

Analog Devices Smart Agriculture Manager Erick Olsen (center) and Senior Engineer Rob O’Reilly are pictured alongside ConVal Regional High School Farm to Fork Fellows viewing tomatoes grown with the company’s crop monitoring solution. (Photo: Business Wire)

For the project, Analog Devices is providing a prototype version of its crop monitoring solution, which will be capable of measuring environmental factors that help farmers make sound decisions about crops related to irrigation, fertilization, pest management, and harvesting. The sensor-to-cloud, Internet of Things solution enables farmers to make better decisions based on accumulated learning from the near-real-time monitoring. These 24/7 measurements are combined with a near infrared (NIR) miniaturized spectrometer that conducts non-destructive analysis of food quality not previously possible in a farm environment.

The Cornucopia Project, a non-profit located in Peterborough, N.H., provides garden and agricultural programs to students from elementary through high school. Student farmers in its Farm to Fork program learn how to use advanced sensor instrumentation in their greenhouse, which provide valuable data to assess the attributes of tomatoes, and how these factors affect taste and quality. The program also educates students on how crops can be tracked throughout the agricultural supply chain to support food quality, sustainability, traceability and nutrition.

ripe.io is contributing its blockchain technology to model the entire fresh produce supply chain, combining the crop growing data, transportation, and storage conditions. Blockchain – a distributed ledger, consensus data technology that is used to maintain a continuously growing list of records – will track crop lifecycle from seed to distributor to retailer to consumer, bringing transparency and accountability to the agricultural supply chain.

Analog Devices | www.analog.com

Don’t Miss Our Newsletter: Microcontroller Watch

Circuit Cellar’s Microcontroller Watch newsletter is coming to your inbox tomorrow. This newsletter keeps you up-to-date on latest microcontroller news. We examine the microcontrollers along with their associated tools and support products.20150220-rh850-d1x

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 “Microcontroller Watch” 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:

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.

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.

Current Multipliers Improve Processor Performance

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

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

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

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

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

Vicor | www.vicorpower.com

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.

Hot-Chips-Stratix-10-board-1-

 

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 | www.microsoft.com

Numeric Precision vs. DDS Calculations

Using the full frequency resolution of a direct digital synthesizer chip outstrips the capabilities of floating point numbers. Ed takes a look at what’s needed for high-resolution frequency calibration and measurements.

By Ed Nisley

As you saw in my July article, the filter bandwidths and frequency resolution required to characterize low-frequency quartz resonators far exceeded the capabilities of my bench instruments. I decided to take a look at building a special-purpose resonator tester around a cheap direct digital synthesizer sine-wave source, because DDS generators have

PHOTO 1 A knockoff Arduino Nano controls a generic AD9850 direct digital synthesizer circuit, both plugged into standard 0.1 inch headers, with hand-wiring connections below the proto board. The SMA connector provides a mechanically rugged output from the board; the DDS frequencies don’t require its RF properties.

PHOTO 1
A knockoff Arduino Nano controls a generic AD9850 direct digital synthesizer circuit, both plugged into standard 0.1 inch headers, with hand-wiring connections below the proto board. The SMA connector provides a mechanically rugged output from the board; the DDS frequencies don’t require its RF properties.

advantages over traditional analog oscillators and frequency counters in computer-controlled measurement systems.

Of course, nothing is ever so simple as it seems. In this article, I’ll explain how numeric precision affects Direct Digital Synthesis (DDS) output frequency calculations, work through the effects of floating-point and fixed-point arithmetic, and show how a carefully tweaked DDS oscillator frequency varies with temperature.

DDS Calculations

You can think of a direct digital synthesizer as a lookup table holding the digitized values of an analog waveform, a counter addressing the table entries in ascending order, and a DAC converting the numbers to analog voltages. The Analog Devices AD8950 DDS chip in Photo 1 has the equivalent of a table with 232 10-bit entries defining a sine wave, a counter clocked at 125 MHz, and a differential output current-mode DAC. The PCB, complete with the DDS and a 125 MHz quartz oscillator, costs under $20 on eBay or Amazon. …

Read the full article in the September 326 issue of Circuit Cellar

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Or purchase the September 2017 issue at the  CC-Webshop

Mouser Provides Microsemi PolarFire FPGA Evaluation Kit

Mouser Electronics is now offering the PolarFire Evaluation Kit from Microsemi, which allows designers to evaluate the highly regarded PolarFire FPGA product family. The flash-based PolarFire FPGAs deliver 100K to 500K logic elements at up to 50 percent lower power consumption than equivalent SRAM-based FPGAs, as well as best-in-class security and reliability.

The Microsemi PolarFire Evaluation Kit, available to order from Mouser Electronics, provides a robust hardware design platform based on a 300K logic element PolarFire FPGA with DDR4, DDR3 and SPI-flash memory. The onboard FPGA integrates reliable PRINT_Microsemi PolarFire Eval Kitnon-volatile FPGA fabric, 12.7 Gbps transceivers, 1.6 Gbps inputs and outputs (I/Os), best-in-class-performance, hardened security IP, and crypto processors. The silicon features power optimization with the lowest static power for mid-range FPGAs, while the Flash Freeze mode yields best-in-class standby power.

The evaluation kit includes SMA connectors for testing the transceiver channel, high pin count FPGA mezzanine card, x4 PCIe edge connector, dual Gigabit Ethernet connectors, and programming using an on-board embedded FlashPro5 programmer. The kit provides high-performance evaluation for a variety of applications, such as industrial automation, cellular infrastructure, security, imaging and video, and USB.

The kit also ships with a one-year Libero Gold Software License, which includes the Libero SoC PolarFire Design Suite of comprehensive, easy-to-learn, easy-to-adopt development tools. The suite integrates industry-standard Synopsys Synplify Pro synthesis and Mentor Graphics ModelSim simulation with best-in-class constraints management and debug capabilities.

Mouser Electronics | www.mouser.com