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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

Reference Design Addresses Demand for Voice Control

Silicon Labs recently released a new, cost-effective solution for voice-enabled ZigBee remote controls. The ZigBee Remote Control (ZRC) reference design reduces the need for expensive external hardware by implementing a software-based audio codec into a single-chip wireless SoC. It includes all of the hardware and software necessary for developing full-featured, voice-enabled remote controls.SiLabs Zigbee

The ZRC reference design is based on Silicon Labs EM34x wireless SoCs and ZRC 2.0 Golden Unit-certified software stack, which provides an industry-standard way to implement interoperable, low-power RF remote controls. The reference design includes complete RF layout and design files, an acceleration sensor for backlight control, a buzzer for “find me” capabilities, support for IR control, a digital microphone, and the ability to transmit voice commands over RF.

Silicon Labs offers two development kits the voice-enabled reference design. The  $249 EM34X-VREVK Voice Remote Evaluation Kit features preprogrammed devices and a simple GUI to demonstrate remote control capabilities, including RF, voice commands, and legacy IR support. The $399 EM34X-VRDK Voice Remote Development Kit provides you with an “out-of-the-box” design experience. It simplifies development of the remote control and target devices, and it comes with an EM34x voice-enabled remote control, USB stick, EM34x development board, EM34x wireless modules, and ISA3 debug adapter.

Samples and volume quantities of Silicon Labs’s EM34x SoCs are available with prices starting at $1.68 in 10,000-unit quantities.

Source: Silicon Labs

New LDO Regulators Deliver clean output voltage to MCUs

Intersil Corp. recently launched the SL80510 and ISL80505, which are two new single-output, low-dropout (LDO) voltage regulators that provide impressive dropout and transient performance for noise-sensitive loads. They deliver 1 A and 0.5 A of continuous output current and ultra-low dropout of 130 mV and 45 mV at full load, respectively. The ISL80510’s maximum dropout is approximately 50% lower than the nearest competitor, which enables lower power dissipation in industrial, wireless, and wired equipment.

The LDOs also provide better transient performance with peak-to-peak excursions up to nine times lower than otherLDOs. This transient performance level and DC accuracy of 1.8% safeguards against voltage undershoots and overshoots to deliver clean point-of-load voltage to CPUs, DSPs, and MCUs, which require tight voltage accuracy and low noise. The ISL80510/05’s compensation loop provides excellent noise filtering by maintaining a flat power supply rejection ratio (PSRR) response over a wide range of frequencies.ISL80510_Intersil

The ISL80510 operates from input voltages of 2.2 to 6 V. The ISL80505 supports 1.8 to 6 V. Since LDOs’ output voltage can be adjusted from 0.8 to 5.5 V, you can cover a broad range of applications, such as low-power RF amplifiers, communications equipment, and consumer network routers. An adjustable soft-start feature enables you to control the input inrush current and program the start-up time to accommodate any power-up sequencing requirement.

Specifications and features of ISL80510 and ISL80505:

  • ISL80510 provides dropout of 130 mV at Vout of 2.5 V with a 1-A load current
  • ISL80505 provides ultra-low dropout of 45 mV at Vout of 2.5 V with a 500-mA load current
  • Stable operation with a small 4.7-μF output ceramic capacitor
  • Delivers ±1.8% Vout accuracy guaranteed over line, load, and junction temperature range of –40°C to 125°C
  • Programmable output soft-start supports sequencing and helps power supply designer control inrush current
  • Current limit protection and thermal shutdown function safeguards against excessive load current or operating temperature
  • Both LDOs are pin-to-pin compatible and supplied in thermally enhanced 8-lead, 3 mm × 3 mm DFN packages

The ISL80510 and ISL80505 cost $0.39 1,000-unit quantities. The ISL80510EVAL1Z evaluation board costs $20.

Source: Intersil Corp.

Small, Low-Power Battery Management Solution for the IoT

Texas Instruments’s new bq25120 battery management solution features low quiescent current (Iq) at 700-nA with the buck converter and operates at 1.8 V. Supporting batteries from 3.6-V to 4.65-V, and fast charge currents from 5-mA to 300-mA, the bq25120 enables wearables and Internet of Things (IoT) applications to remain on without draining the battery. TI Battery1

The bq25120 includes a linear charger, configurable LDO, buck converter, load switch, push button control, and battery voltage monitor. You can use it with other devices to integrate more end application features.

With the $99 bq25120 evaluation module (EVM), you can speed up time to market by easily evaluating device features and performance. The 2.5 mm × 2.5 mm bq25120 charger costs $1.60 in 1,000-piece quantities.

Source: Texas Instruments

Parts.io Vendor-Independent Search Engine Goes Live

Parts.io recently launched and announced that it is live, fully open, and free for anyone to use in their search for electronic components.  According to Parts.io, you can search over 135 million electronic components by category, availability, popularity, and price across a global network of distributors and manufacturers. The platform offers a visual representation of complex data, enabling engineers to make the best component selection for their projects and allows users to order directly from their favorite supplier through the platform.partsIO

“Component selection is a critical step in the design cycle, often impacting production schedules six months or more down the line. Parts.io offers a transparent way to compare and select the best components based on reliable data and big data analysis,” says Chris Gammell, Product Lead for Parts.io, which is part of the SupplyFrame engineering network. Visit Parts.io for more information.

Source: Parts.io

Workspace for Electromechanical Innovation

Many Circuit Cellar readers dabble in both mechanical and electrical design. Jared Harvey—a senior electrical engineer at Howell Laboratories—recently shared with us a photo and description of his home workspace in West Newfield, ME, where he tackles interesting electromechanical projects.JH_workspace

Here is what he says about his space:

I was once told that a clean work space is a sign of a dirty mind. I hope that holds true in the inverse as my work space is always messy. For hobby stuff, I can never seem to prioritize the cleaning operations, I pretty much always choose to put those energies into building something.

Located in the basement, on the left is an oak bench with a vise, which is used for mostly mechanical stuff, in the middle is a metal bench for mostly electrical stuff. on the right is another metal bench for anything else. Also in view is an old drill press and one of those circular magnification glasses with a light, mounted on a move-able arm. I also have a large-ish garage with car lift, which allow for larger projects like the little red suby.

I have a small collection of electrical tools including HAMEG spectrum analyzer, DSO Quad, China logic analyzer, Metcal soldering station, and a couple misc bench top power supplies and misc function generators. It’s pretty basic tools, and whenever I need real tools I have always had access to good NIST traceable tools at work. I have made a re-flow toaster oven out of an B&D Infrawave, which is PID controlled using a thermo-couple controlled and generates mostly IR as well as some conduction heaters in the bottom.

Someday I’d like to help develop an open source multi meter, also I’d like to re-purpose my old AC units making them into a geothermal heat ex-changer. Lately I’ve been spending a bunch of time helping develop rusEFI, and in the past have helped with project like OpenServo. Projects these days have limited time as the 5 year old and 7 year old are higher priority and take up most of my spare time. So it’s generally 10 minutes a day late night or early morning.

Visit Jared’s webpage to read about his projects, including the following: FEA Magnetic encoder Analysis, Radio Propagation Analysis, and Solid Modeling and Gif Animation.

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October Electrical Engineering Challenge Live (Sponsor: NetBurner)

Ready to put your electrical engineering skills to the test? The October Electrical Engineering Challenge (sponsored by NetBurner) is live.

This month, find the error in the schematic posted below (and on the Challenge webpage) for a chance to win a NetBurner MOD54415 LC Development Kit ($129 value) or a Circuit Cellar Digital Subscription (1 year).


Click the image to enlarge. Find the error in this schematic and submit your answer by October 20, 2015.

Find the error in this schematic and submit your answer by October 20, 2015. Submit via the Challenge webpage. Click image to access submission form.


Out of each month’s group of entrants who correctly find the error in the code or schematic, one person will be randomly selected to win a NetBurner IoT Cloud Kit and another person will receive a free 1-year digital subscription to Circuit Cellar.

  • NetBurner MOD54415 LC Development Kit: You can add Ethernet connectivity to an existing product or use it as your product’s core processor! The NetBurner Ethernet Core Module is a device containing everything needed for design engineers to add network control and to monitor a company’s communications assets. The module solves the problem of network-enabling devices with 10/100 Ethernet, including those requiring digital, analog, and serial control.NetburnerMod54415module
  • Circuit Cellar Digital Subscription (1 year): Each month, Circuit Cellar magazine reaches a diverse international readership of professional electrical engineers, EE/ECE academics, students, and electronics enthusiasts who work with embedded technologies on a regular basis.Circuit Cellar magazine covers a variety of essential topics, including embedded development, wireless communications, robotics, embedded programming, sensors & measurement, analog tech, and programmable logic.


Read the Rules, Terms & Conditions


NetBurner solves the problem of network enabling devices, including those requiring digital, analog and serial control. NetBurner provides complete hardware and software solutions that help you network enable your devices.

NetBurner, Inc.
5405 Morehouse Dr.
San Diego, CA 92121 USA

Build a Three-in-One Measurement System

No home electronics lab is complete without a signal generator, logic analyzer, and digital oscilloscope. But why purchase the measurement devices separately, when you can build one system that houses all three? The process is easier than you’d expect.

Hand-soldering a package this size is tough work. The signal-generator filter has bulky coils. In contrast, the MSP430F149’s PQFP64 is tiny.

Photo 1: Hand-soldering a package this size is tough work. The signal-generator filter has bulky coils. In contrast, the Texas Instruments MSP430F149’s PQFP64 is tiny.

Salvador Perdomo writes:

I’ve built an inexpensive and versatile measurement system that contains a signal generator, logical analyzer, and digital oscilloscope. If you build your own, you’ll be able to address many of the problems typically encountered on test benches.

The system is not PC-bus connected. Instead, it’s external to the computer, making use of the RS-232 serial port shown in Figure 1. Also, it doesn’t have a power supply input, so the same serial cable feeds it. Because the computer’s serial connection provides limited power, low power consumption is a fundamental requirement.

It is of interest to have your test benches as clear as possible to search for the faulty part of your design. So, a small measurement system is highly recommended. It’s better if it isn’t connected to the mains.

Figure 1: It is of interest to have your test benches as clear as possible to search for the faulty part of your design. So,a small measurement system is highly recommended. It’s better if it isn’t connected to the mains.

The low-power goal is achieved with a small number of components—the fewer the better. So, I quickly became interested in the Texas Instruments MSP430F149, which is a highly integrated device with low power consumption. Note that everything is integrated except the oscilloscope analog chain (coupling and programmable amplifier), part of the trigger circuit, and the input buffer for the logic analyzer. The microcontroller works with an 8-MHz crystal oscillator.

This application uses the register bank, the entire RAM (2 KB), and nearly all of the peripherals. The peripherals used include the 16-bit TimerA and B, ADC, analog comparator, multiply accumulate, and one USART with modulation capability. Only the second USART is spared.

The system has several main features. You can control and display on the PC by running software implemented on LabWindows/CVI. In addition, it has a signal generator based on the direct digital synthesis method and a frequency of up to 6 kHz with 0.3-Hz resolution. The output voltage reaches a peak of 1.3-V (±2 dB) fixed amplitude. The signal generator works simultaneously with the oscilloscope and logic analyzer (but not these two).

I included a digital oscilloscope with two channels that have 1-MHz bandwidth, 8 bits of resolution, and 401 words of memory per channel. There are 10 amplitude scales from 5 mV to 5 V per division and 18 timescales from 5 μs to 2.5 s per division. Note that there are four working modes: Auto, Normal, Single, and Roll.The logic analyzer has eight channels, 1920 words of memory per channel, and sampling from 1 to 100 kS/s. It is trigger-delay selectable between 0, 50, and 100% of memory length.

Looking at Photo 1, you see that the system’s hardware consists of two separate boards that are attached to each other. Photo 2a shows the tops of the boards, and Photo 2b shows the bottoms.

a—You can replace the relays in the coupling section and the driver circuit with solid-state relays if you can find ones with low leakage current. b—The op-amp’s SMD packages are best viewed from the bottom. The larger board is populated on both sides. Note the importance of the parasitic coupling of the PWM D/A outputs to the input of the amplifiers.

Photo 2: a—You can replace the relays in the coupling section and the driver circuit with solid-state relays if you can find ones with low leakage current. b—The op-amp’s SMD packages are best viewed from the bottom. The larger board is populated on both sides. Note the importance of the parasitic coupling of the PWM D/A outputs to the input of the amplifiers.

The larger board contains the oscilloscope analog chain: BNC connectors, relays (and circuit controller) for DC-GND-AC in the coupling section, and the digital programmable attenuator/amplifier. The top board contains the DC/DC converter power supply, charge-pump inverter, serial communication driver, low-pass filter, trigger (real and equivalent time sampling) circuit, channel-trigger selector, and the microcontroller.

Download the entire article.

Electrical Engineering Challenge: September Winners (Sponsored by NetBurner)

The answer to the September Electrical Engineering Challenge is now live. Congratulations to the winners: John Barraclough (United Kingdom) and Pieter Willemsen (Belgium).

The error is in line 28. There needs to be a second open parenthesis.

The next Challenge launches on October 1, 2015. Good luck!

Two Sensors Get the Bigger Picture: High-Performance Smart Cameras for OEM Applications

Featuring a very compact footprint as well as excellent usability, Vision Components VCSBCnano Z-RH-2 series embedded cameras enable high-speed image processing in real time. The ultra-small products are available for cost-sensitive OEM applications where installation space is limited. The smart cameras are equipped with a Xilinx ZYNQ dual-core Cortex A9 ARM processor clocked at 2 × 866 MHz, which comes with an integrated FPGA running the VC Linux operating system. The miniature board dimensions of 40 × 65 mm for the main board and 24 × 18 mm for the sensor boards combined with custom installation and connection options facilitate a flexible integration into industrial or other applications (e.g., high-speed and line camera applications).Vision Components - pinguin

Two external sensor boards connected to the CPU board via 30 mm or 80 mm ribbon cables (other lengths on request) enable stereo vision applications. Vision Components also provides models with an on-board sensor or single external sensor to give users maximum flexibility for machine or robot integration.

All VCSBCnano Z-RH-2 cameras feature 12 programmable inputs and outputs, an optically isolated trigger output, a flash trigger, Gbit Ethernet interface, RS-232 interface, and I²C interface. They are available with five different CMOS sensors with a global shutter that provide resolutions up to 4.2 Megapixels. An optional IP67 case, either with or without integrated optics and lighting, ensures protection in harsh environments. For users seeking to fully exploit the performance potential of the hardware, Vision Components also offers an FPGA programming service which can accelerate processing speeds many times over. Like all VC cameras, VCSBCnano Z series cameras come complete with the free-of-charge VCLib software library, which provides over 300 basic industrial image processing functions such as pattern matching.

Source: Vision Components

Fast 600-V Gate Driver Reduces System-Solution Size for MOSFETs and IGBTs

Texas Instruments recently introduced the UCC27714 half-bridge gate driver for discrete power MOSFETs and IGBTs that operate up to 600 V. With 4-A source and 4-A sink current capability, the UCC27714 reduces component footprint by 50%. In addition, it provides 90-ns propagation delay, 40% lower than existing silicon solutions, tight control of the propagation delay with a maximum of 125 ns across –40°C to 125°C and tight channel-to-channel delay matching of 20 ns across –40°C to 125°C.  The device eliminates the need for bulky gate drive transformers, saving significant board space in high-frequency switch-mode power electronics.TI-gatedriver

Key features and benefits include:

  • Smaller footprint creates highest power-density solutions
  • Advanced noise toleration
  • MOSFETs have the ability to drive over a wide power range
  • Operates across wide temperatures

The UCC27714 is now available. The high-speed 600-V, high-side low-side gate driver costs $1.75 in 1,000-unit quantities.

Source: Texas Instruments

RF Chip Family Enables Secure, Long-Range Smart Car Communication

NXP Semiconductors has announced the new Mantra RF family of high-performance transceivers and receivers for secure car access and vehicle management. The chip family offers a long-range (several hundred meters), two-way RF link for bidirectional communication between a key fob and car. NXP_CarKeyChip

Keys with Mantra enable you to remotely check your vehicle’s fuel, battery levels, and maintenance data. In addition, you can check if the doors and windows are locked, as well remotely operate your vehicle’s locks, ignition, and temperature. Furthermore, the Mantra family provides strong security and authentication features to prevent unauthorized access.

The Mantra RF family’s features include:

  • Multichannel transceiver and receiver solutions
  • Single IC for bands (315, 345, 426, 434, 447, 868, 915, and 950 MHz)
  • Simultaneous reception of up to three channels in parallel
  • Two RF inputs allowing sequential antenna diversity
  • Low receiver power consumption
  • Flexible customization at ultra-low power with the programmable microcontroller core
  • High-performance, low-noise front end

Source: NXP Semiconductors http://www.nxp.com/

The Future of Commodity Hardware Security and Your Data

The emergence of the smartphone industry has enabled the commodity hardware market to expand at an astonishing rate. Providers are creating cheap, compact, and widely compatible hardware, which bring about underestimated and unexplored security vulnerabilities. Often, this hardware is coupled with back end and front end software designed to handle data-sensitive applications such as mobile point-of-sale, home security, and health and fitness, among others. Given the personal data passed through these hardware devices and the infancy of much of the market, potential security holes are a unique and growing concern. Hardware providers face many challenges when dealing with these security vulnerabilities, foremost among them being distribution and consequent deprecation issues, and the battle of cost versus security.

The encryption chip for the Square Reader, a commodity hardware device, is located in the bottom right hand corner instead of on the magnetic head. This drastically reduces the cost of the device.

The encryption chip for the Square Reader, a commodity hardware device, is located in the bottom right hand corner instead of on the magnetic head. This drastically reduces the cost of the device.

An important part of designing a hardware device is being prepared for a straightforward hardware deprecation. However, this can be a thorn in a provider’s side, especially when dealing with widespread production. These companies create on the order of millions of copies of each revision of their hardware. If the hardware has a critical security vulnerability post-distribution, the provider must develop a way to not only deprecate the revision, but also fix the problem and distribute the fix to their customers. A hardware security vulnerability can be very detrimental to companies unless a clever solution through companion software is possible to patch the issue and avoid a hardware recall. In lieu of this, products may require a full recall, which can be messy and ineffective unless the provider has a way to prevent future, malicious use of the insecure previous revision.

Many hardware providers have begun opting out of conventional product payments and have instead turned to subscription or use-based payments. Hence, the provider may charge low prices for the actual hardware, but still maintain high yields, typically through back end or front end companion software. For example, Arlo creates a home security camera with a feature that allows users to save videos through their cloud service and view the videos on their smartphone. The price of the camera (their hardware) is mid-range when measured against their competitors, but they charge a monthly fee for extra cloud storage. This enables Arlo to have a continual source of income beyond their hardware product. The hardware can be seen as a hook to a more stable source of income, so long as consumers continue to use their products. For this reason, it is critical that providers minimize costs of their hardware, even down to a single dollar—especially given their large-scale production. Unfortunately, the cost of the hardware is typically directly related to the security of the system. For example, a recent vulnerability found by me and my colleagues in the latest model Square Reader is the ability to convert the Reader to a credit card skimmer via a hardware encryption bypass. This vulnerability was possible due to the placement of the encryption chip on a ribbon cable offset from the magnetic head. If the encryption chip and magnetic head had been mounted to the Reader as an assembly, the attack would not have been possible. However, there is a drastic difference in the cost, on the order of several dollars per part, and therefore security was sacrificed for the bottom line. This is the kind of challenging decision every hardware company has to make in order to meet their business metrics, and often it can be difficult to find a middle ground where security is not sacrificed for expense.

New commodity hardware will continue to integrate into our personal lives and personal data as it becomes cheaper, more compact, and universally compatible. For these reasons, commodity hardware continues to present undetermined and intriguing security vulnerabilities. Concurrently, hardware providers confront these demanding security challenges unique to their industry. They face design issues for proper hardware deprecation due to massive distribution, and they play a constant tug-of-war between cost constraints and security, which typically ends with a less secure device. These potential security holes will remain a concern so long as the smartphone industry and commodity hardware market advance.

Alexandrea Mellen is the founder and chief developer at Terrapin Computing, LLC, which makes mobile applications. She presented as a briefing speaker at Black Hat USA 2015 (“Mobile Point of Scam: Attacking the Square Reader”). She also works in engineering sales at The Mellen Company, which manufactures and designs high-temperature lab furnaces. She has previously worked at New Valence Robotics, a 3-D printing company, as well as The Dorm Room Fund, a student-run venture firm. She holds a BS in Computer Engineering from Boston University. During her undergraduate years, she completed research on liquid metal batteries at MIT with Group Sadoway. See alexandreamellen.com for more information.

USB Type-C with Texas Instruments TUSB320 CC Logic and Port Controllers from Mouser

Mouser Electronics is now stocking the Texas Instruments TUSB320 family of USB Type-C configuration channel logic and port controllers from Texas Instruments (TI). The TUSB320 family of devices provide USB Type-C configuration channel (CC) logic and port control, making it possible for a system to detect the orientation of the plug, and determine the appropriate USB specification and mode settings for the end equipment.Mouser TUSB320

The TI TUSB320 devices, available from Mouser Electronics, can be configured as a downstream-facing port (DFP), upstream-facing port (UFP), or a dual-role port (DRP). The family of products supports USB 2.0 and USB 3.1, giving designers the flexibility to use these devices in multiple USB-enabled designs. The TUSB320 family also contains several features (such as mode configuration and low standby current), which make this device applicable for source or sinks in USB 2.0 applications. The device operates over a wide supply range (2.7Vbus – 5.5Vbus) and offers low power consumption; its low shutdown power of 8 mW benefits a variety of battery-powered applications.
The TUSB320 family of devices offers I2C or GPIO control, an industrial temperature range of -40 to +85 degrees Celsius, and support for up to 3A advertisement and detection. The devices can be used for host, device, and dual-role port applications in mobile phones, tablets, and USB peripherals.

The TUSB320EVM, also available from Mouser Electronics, provides an evaluation platform for the TUSB320 device. This plug-and-play module is configurable via onboard DIP switches for DFP, UFP, or DRP implementations, operating in I2C or GPIO mode.

Source: Mouser

Dialog to Buy at Atmel for $4.6 Billion

Dialog Semiconductor and Atmel Corp. recently announced Dialog will acquire Atmel in a cash and stock transaction for approximately $4.6 billion. According to reports, the deal will likely close in the first quarter of 2016.

The transaction—which has been unanimously approved by the boards of directors of both companies and is subject to regulatory approvals in various jurisdictions, as well as the approval of Dialog and Atmel shareholders—will likely close in Q1 2016. Jalal Bagherli will continue as Chief Executive Officer and Executive Board Director of Dialog.

Evaluation Boards for SuperSpeed USB-to-FIFO Bridge ICs

FTDI recently launched a new family of evaluation/development modules to encourage the implementation of its next-generation USB interfacing technology. Its FT600/1Q USB 3.0 SuperSpeed ICs are in volume production and backed up by the UMFT60XX offering. The family comprises four models that provide different FIFO bus interfaces and data bit widths. With these modules, the operational parameters of FT600/1Q devices can be fully assessed and interfacing with external hardware undertaken, such as FPGA platforms.

At 78.7 mm × 60 mm, the UMFT600A and UMFT601A each have a high-speed mezzanine card (HSMC) interface with 16-bit-wide and 32-bit-wide FIFO buses, respectively. The UMFT600X and UMFT601X measure 70 mm × 60 mm and incorporate field-programmable mezzanine card (FMC) connectors with 16-bit-wide and 32-bit-wide FIFO buses, respectively.

The HSMC interface is compatible with most Altera FPGA reference design boards, while the FMC connector delivers the same functionality in relation to Xilinx boards. Fully compatible with USB 3.0 SuperSpeed (5 Gbps), USB 2.0 High Speed (480 Mbips), and USB 2.0 Full Speed (12 Mbps) data transfer, the UMFT60xx modules support two parallel slave FIFO bus protocols with an achievable data burst rate of around 400 MBps. The multi-channel FIFO mode can handle up to four logic channels. It is complemented by the 245 synchronous FIFO mode, which is optimized for more straightforward operation.

Source: FTDI