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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

High Efficiency, Highly Integrated 8A and 3A Synchronous Buck Regulators

Intersil Corp. recently announced five new highly integrated synchronous buck regulators that step-down 5-V rails to point-of-load (POL) inputs as low as 0.6 V for FPGAs, DSPs, and microprocessors. The ISL8018 delivers up to 8 A of continuous output current from a 2.7-to-5.5-V input supply. In addition, it provides up to 97% efficiency and higher integration than similar devices.

The ISL8003x devices deliver up to 3 A of continuous output current from a 2.7-to-5.5-V input supply and offer up to 95% peak efficiency for delivering general POL conversions. Useful in telecom, cloud computing, industrial, and medical equipment, the ISL8018 provides an innovative SYNCIN and SYNCOUT feature that connects and synchronizes multiple regulators at the same switching frequency in a master/slave configuration using a phase shifting time delay. With the ISL8018’s VSET feature, the voltage output margining can be set at 10% to compensate for output voltage IR drop. The ISET feature provides programmable output current limits to support 8-, 5-, and 3-A applications. This allows customers to leverage one design with smaller inductors for reduced costs and board area. In addition, the ISL8018’s programmable switching frequency from 500 kHz up to 4 MHz enables the use of smaller passive components for faster transient response and further board space savings.

Key features and specifications:

  • High peak efficiency up to 97%
  • Converter occupies less than 97 mm2 of board space
  • ±10% output voltage margining
  • Output voltage is adjustable from 0.6 V to Vin, with a fixed output voltage option
  • External synchronization up to 4MHz, with master-to-slave phase shifting capability
  • Adjustable switching frequency from 500 kHz to 4 MHz, with default at 1 MHz
  • Start-up with pre-bias output, internal soft-start—1 ms or adjustable, internal/external compensation
  • Soft-stop output discharge during disabled
  • Peak current limiting, hiccup mode short circuit protection, and over-temperature protection
  • Adjustable current limit

The ISL8018 8A synchronous buck regulator is available in a 3 mm × 4 mm, 20-lead QFN package and it costs $1.60 in 1,000-piece quantities. The ISL8018DEMO1Z demonstration board costs $20. The full-featured ISL8018EVAL3Z evaluation board is $115.

Source: Intersil Corp.

STM32 Family Enabled for the ARM mbed IoT Device Platform

STMicroelectronics has announced that the STM32 family of ARM Cortex-M based microcontrollers is now enabled for the ARM mbed IoT Device Platform with the latest public version of the ARM mbed OS. The mbed platform adds a standard OS, cloud services, and development tools for creating new IoT applications.

By adding mbed to its handy design ecosystem, STMicro is encouraging more productivity and collaboration in IoT development. Using the mbed OS with STM32 development hardware enables you to innovate while reducing your product’s time to market. You can easily incorporate STM32 microcontrollers with STMicro’s sensor and power-management products to deploy “smart,” secure IoT designs.

Source: STMicroelectronics

Maker Works (Ann Arbor, MI, USA)

Maker Works is an Ann Arbor, MI-based group with a 14,000-square-foot space for makers interested in electronics, metal, wood, and crafts.Maker_Works_logo

Location 3765 Plaza Drive, Ann Arbor, MI 48108
Members 60+
Website www.maker-works.com

Read about what Co-Founder Dale Grover has to say about Maker Works.

Tell us about your space!

Currently 14,400 sq ft, including a full metal shop, wood shop, electronics (PCB engraver), plastics & fabric, and workstations. “Garages” for parking member carts for storage. Over 3,000 sq ft of office & fabrication space rented to start-ups and small businesses. We are a triple bottom line company: people, planet, profit. We even run a 5-day bootcamp on how to operate a makerspace, which draws from all over the country.

What tools do you have in your space? 

Soldering stations, oscilloscope, 3-D printer, woodshop, CNC, and a data center.

Are there any tools your group really wants or needs?

The next items we are looking to add are powder coating oven and a gas-fired forge.

What’s the craziest, most exciting, and/or most innovating project your group or group members have completed? 

The Great Maker Race, a no-rules race we run at Maker Faires and other events. Attendees use custom-built hot-wire foam cutters to shape cars, then attach wheels and race them down a hilly track. We’ve had kids builds thousands of these cars. Arduino-based timer uses piezo film sensors for finish gate.

Do you have any events or initiatives you’d like to tell us about? Where can we learn more about it? 

Each month we have “Fix-It Friday”. The general public is invited to bring in things as a last-chance to get them fixed. We’ve repaired many lamps, chairs, and a fair amount of consumer electronics. Monthly geek show and tell meeting called GO-Tech meets here (going since 2007): https://groups.yahoo.com/neo/groups/notbago/info. Lots of great electronics, CNC, basic physics, historical technology, etc.

Can you tell us about some of your group’s recent tech projects? 

About 4 FIRST robotics teams use Maker Works as their build location, so we always have interesting robotics going on. Other members design their own controllers for RC helicopters. The shop is working on a third generation of an RFID system for monitoring tool usage (ESP8266). Many projects shown on our Facebook page.

Read more about Maker Works on its website

Show us your hackerspace! Tell us about your group! Submit here. Where does your group design, hack, create, program, debug, and innovate? Do you work in a 20′ × 20′ space in an old warehouse? Do you share a small space in a university lab? Do you meet at a local coffee shop or bar? What sort of electronics projects do you work on? Submit today.

Arcturus uCMK64-IoT module: TLS security, Ethernet, Wi-Fi and more (Sponsored)

The Arcturus uCMK64-IoT is a 60x60mm module for developing secure IoT devices that require a combination of connectivity and control. The hardware uses a 120MHz, Freescale Kinetis K64 microcontroller with Ethernet, Wi-Fi, TLS security, peripheral connectivity and optional audio. The platform is controlled using a simple command protocol over a UART or TCP/IP socket, providing options for both host-MCU or cloud integration. The protocol supports I/O, bi-directional UART-to-net communication, device services and settings. A “call home” feature automatically originates the secure TLS socket connection to a remote server, helping to egress firewalls.

uCMK64-MOD-Top_PennyThe platform is fully compatible with the eco-system of Arcturus IoT tools, including Mbarx-System Manager, a powerful tool for securely managing entire network sites. Developers can easily connect, change firmware, configure, control or probe attached sensors and peripherals. An IoT apps store, provides direct access to firmware.

The uCMK64 is IoT made easy, no complex BSP or software system integration. The development kit contains everything you need to get started.

uCMK64-Kit_ContentsKey features:

  • 120MHz ARM® Cortex® M4 microcontroller
  • Ethernet with network stack
  • 11bgn Wi-Fi
  • Optional audio
  • Socket or UART control
  • Eco-system of IoT Tools
  • -40 to +85C parts rating


  • TLS based secure connectivity
  • I/O controls
  • UART-to-net peripheral connectivity
  • Optional VoIP, audio and PA firmware

How to buy:

  • uCMK64-IoT Development Kit
  • uCMK64-MOD – Module
  • uCMK64-SSB – Board

Learn more at ArcturusNetworks.com


Submitting to Circuit Cellar Just Got Easier

submit imageCircuit Cellar’s new online article and proposal submission form makes contributing easier than ever. Check it out.

Circuit Cellar publishes articles (Circuit Cellar magazine), books, and website content by talented authors on electrical engineering-related topics. When you publish with Circuit Cellar, you are reaching an educated professional audience of engineers, programmers, and academics around the globe. Professional engineers, academics, students, and serious electronics enthusiasts are encouraged to submit articles and proposals.

Our editors carefully review all proposals and finished submissions before making final decisions about publication. The review process can take a few weeks. Your work must be your own and original. Your article should meet all the requirement specified in the Authors Guide.

2016 Editorial Calendar

  • 306 January – Embedded Applications
  • 307 February – Wireless Communications
  • 308 March – Robotics
  • 309 April – Embedded Programming
  • 310 May – Measurement & Sensors
  • 311 June – Communications
  • 312 July – Internet & Connectivity
  • 313 August – Embedded Development
  • 314 September – Data Acquisition
  • 315 October – Signal Processing
  • 316 November – Analog Techniques
  • 317 December – Programmable Logic

You can either use our online submission form or email our editors at editor@circuitcellar.com.

Next-Gen Bluetooth Low Energy Solutions

Microchip Technology recently launched next-generation Bluetooth Low Energy (LE) solutions intended for Internet of Things (IoT) and Bluetooth Beacon applications: the IS1870 Bluetooth LE RF module, the IS1871 Bluetooth LE RF module, and the BM70 module.Microchip BM70

The Bluetooth LE devices include an integrated, certified Bluetooth 4.2 firmware stack. Data is transmitted over the Bluetooth link using Transparent UART mode, which you can integrate with any processor or PIC microcontroller with a UART interface. The module also supports standalone “hostless” operation for beacon applications.

The optimized power profile of these new devices minimizes current consumption for extended battery life, in compact form factors as small as 4 × 4 mm for the RF ICs and 15 × 12 mm for the module. The module options include RF regulatory certifications, or noncertified (unshielded/antenna-less) for smaller and more remote antenna designs that will undergo end-product emission certifications.

The BM70 Bluetooth Low Energy PICtail/PICtail Plus daughter board enables code development via USB interface to a PC. Or you can connect to Microchip’s existing microcontroller development boards, such as the Explorer 16, PIC18 Explorer and PIC32 I/O Expansion Board. The BM-70-PICTAIL costs $89.99.

The IS1870 Bluetooth LE RF IC (6 × 6 mm, 48-pin QFN package) costs $1.79 in 1,000-unit quantities. The IS1871 (4 × 4 mm, 32-pin QFN package) costs $1.76 in 1,000-unit quantities. The 30-pin BM70 Bluetooth LE modules are available with or without built-in PCB antennas, starting at $4.99 each in 1,000-unit quantities.

Source: Microchip Technology

Starter Kit for State Machine-Based Development for Embedded Systems

IAR Systems recently announced a starter kit for the state machine toolset IAR visualSTATE. Aimed at developers interested in exploring state machine-based embedded development, it includes evaluation versions of IAR visualSTATE as well as the embedded development toolchain IAR Embedded Workbench. The kit’s evaluation board comprises an STMicroelectronics STM32F429 and an I-jet Lite debug probe. VS IAR

You can use IAR visualSTATE to develop design from a high level. In addition, the tools offer advanced formal verification, analysis, and validation. It contains an easy-to-use evaluation board that can be powered via the included debug probe I-jet Lite, which provides JTAG and SWD debug interfaces.

IAR visualSTATE is completely integrated with the powerful C/C++ compiler and debugger toolchain IAR Embedded Workbench. When using the tools together, full state machine debugging on hardware is available.

IAR KickStart Kit for visualSTATE costs $209.

Source: IAR Systems

Time-of-Flight IC for Distance Measurement & Object Detection

Intersil Corp.’s low-power ISL29501 time-of-flight (ToF) signal processing IC is an object detection and distance measurement solution when combined with an external emitter (e.g., LED or laser) and photodiode. Intended for Internet of Things (IoT) applications and consumer mobile devices, the ISL29501 offers precision long-range accuracy up to 2 m in both light and dark ambient light conditions. You can select an emitter and photodiode and then configure a custom low-power ToF sensing system. intersil ISL29501

The ISL29501’s on-chip emitter DAC with programmable current up to 255 mA enables you to select the desired current level for driving the external infrared (IR) LED or laser. This feature enables optimization of distance measurement, object detection, and power budget. In addition, the ISL29501 can perform system calibration to accommodate performance variations of the external components across temperature and ambient light conditions.

The ISL29501’s main specs and features:

  • On-chip DSP calculates ToF for accurate proximity detection and distance measurement up to 2 m
  • Modulation frequency of 4.5 MH
  • On-chip emitter DAC with programmable current up to 255 mA a
  • On-chip active ambient light rejection
  • Programmable distance zones
  • Automatic gain control
  • 2.7 to 3.3 V Supply voltage range
  • I2C interface supports 1.8- and 3.3-V bus

The ISL29501 is available in a low profile 4 mm x 5 mm, 24-lead TQFN package for $4.87 USD in 1,000-piece quantities. The ISL29501-ST-EV1Z reference design board costs $250.


New SLC NAND Flash Memory Family for High-Security Apps

Cypress Semiconductor Corp. recently announced a high-endurance, 1-to-4-Gb Single-Level Cell (SLC) SecureNAND family that reduces system costs and improves system security. It does this by providing a single nonvolatile memory with integrated block protection features for a variety of high-security applications, such as point-of-sale systems and wearables.Cypress SecureNAND

The SecureNAND family includes 1-Gb S34SL01G2, 2-Gb S34SL02G2, and 4-Gb S34SL04G2 devices. You can configure each device with nonvolatile block protection to store protected boot code, system firmware, and applications. They provide 100,000 program/erase cycles to ensure more than five years of system life. Their operating voltage range is 2.7  to 3.6 V and they support the industrial temperature range of –40° to 85°C.

The currently sampling 1-Gb S34SL01G2, 2-Gb S34SL02G2, and 4-Gb S34SL04G2 SecureNAND devices are available in a 63-BGA package.

Source: Cypress Semiconductor

Innovations in Mobile Robotics: An Interview with Nick Kohut

Nick Kohut and a lab mate turned their academic interest in mobile robotics into an exciting business—Dash Robotics, which sells a small, insect-like running robot that you can control with a smartphone. We recently asked Nick about advances in running robot technology, the benefits of aerodynamic turning , and his thoughts on the future of robotics.

Nick Kohut (Co-Founder, Dash Robotics)

Nick Kohut (Co-Founder, Dash Robotics)

CIRCUIT CELLAR: When did you become interested in robotics? Can you tell us about your first robotics project?

NICK: I actually first became interested in robotics in 2010, which was my third year of graduate school. I had become an engineer originally because I was really interested in cars, specifically vehicle dynamics. I had just wrapped up my Master’s working on a research project at Cal with Audi, and I needed a new project for my PhD.

I looked around at different labs, and the work being done in Ron Fearing’s robotics lab seemed really interesting—basically vehicles with legs. Believe it or not, I had never done any robotics or even soldered a single joint until that point. I had a steep learning curve in the lab, and my first robotics project was MEDIC, a 4 cm walking robot. It was pretty tough but I learned a lot, and fell in love with the subject.

CIRCUIT CELLAR: Why did you decide to focus your studies on control systems? Whose work inspired you to focus on control systems?

NICK: At the University of Illinois Prof. Andrew Alleyne was one of my advisors, and I took his intro controls course junior year. I really liked it—controls and dynamics are definitely my favorite subject, anything that moves keeps my interest. It also had a lot of math which I was pretty decent at for an engineer so I did really well in the class. I decided I should study it in grad school. What they don’t tell you is that grad school controls is totally different, but I ended up liking that too.

The TAYLRoACH (tail-actuated yaw locomotion roach)

The TAYLRoACH (tail-actuated yaw locomotion roach)

CIRCUIT CELLAR: Tell us about the work you did in the Biomimetics and Dexterous Manipulation Laboratory under Professor Mark Cutkosky.

NICK: I was only in Mark’s lab for about seven months. It was a great place to work, but I had founded Dash Robotics in between taking the postdoc position and actually starting the postdoc. Because of that I only worked on one project and in seven months there’s only so much you can do. I was trying to scale up an Electroactive Polymer actuator (EAP) for use in Honda’s Asimo robot. It’s an interesting challenge that involves a lot of rapid prototyping, materials research, and solid mechanics. Also quality control, which is hard to in a lab setting.

CIRCUIT CELLAR: How did you come to use aerodynamic forces to turn running robots? What led you to this field of research?

NICK: This actually started with biologists like Robert Full and Tom Libby studying lizards. Bob and Tom had discovered that when lizards jump they use their tail as a form of attitude control. They had also shown that in a wind tunnel they will use their tail to turn. I was tasked with getting a robot to turn using a tail, which I did with some pretty good success. TaylRoACH (the robot I built in 2012) ended up being the fastest turning legged robot in the world. It could turn 90° in 1/4 of a second.

After I had shown that, I started to wonder what else the tail could do. I tried a lot of things – mostly back of the envelope ideas—like stability on inclines or using as a “7th leg” in confined places. A lot of those didn’t work out, and someone suggested I use it as a helicopter blade, half-joking. It got me to thinking, what if you used it as a sail? I ran the numbers in like an hour and realized, man, this might actually work.

CIRCUIT CELLAR: What are the benefits of aerodynamic turning?

NICK: There are a few benefits. One interesting thing is that it will only work at small scales, but that’s probably where you want it. When robots start to get smaller and smaller, you become really limited with what you can do. You can’t add a lot of sensors, actuators, or computing power (though this is changing every day!). So you probably have a very simple robot, maybe only a few actuators. The SailRoACH has six legs, and only three actuators, but can make wide turns, rapid turns, and pretty much everything in between. So it can keep things simple.

It also can be used in a research setting to study the dynamics of the robot. If you want to add a constant yaw disturbance to the robot and measure how that affects its running ability, this is a way to do that. This may sound like an esoteric need but it’s how research gets done, and it helps us understand running robots better.

CIRCUIT CELLAR: Tell us about the Millirobot Enabled Diagnostic of Integrated Circuits (MEDIC) project. Why did you start the project and what were the results?

NICK: MEDIC was an interesting project because it was my first robotics project and we were trying to solve a very difficult problem, which was “Can you build a robot to navigate inside a computer motherboard?” We were contracted to work on this with Lockheed Martin, and they supplied the software end of things.

Basically we built this incredibly small robot (~5 cm and 5 g) that had legs and a hull that would allow it to scoot around a motherboard, turn, and climb over basic, short obstacles (like a microchip). I worked on the mechanics and design of the robot, with a lot of help from other lab members on the electronics, and Lockheed provided the software that allowed MEDIC (called “Adorable Turtle Bot” by us) to navigate. It actually had a little camera on it, so it would take a picture, send that information to a laptop, then the laptop would send a few instructions (“go forward two steps, then turn left for two step”), the robot would execute the instructions, take another picture, and repeat the process.

It was pretty cool because you had this tiny robot doing SLAM and navigating autonomously inside a computer motherboard. Unfortunately it was slower than oatmeal running downhill and didn’t work most of the time, but that’s research. By the end we had some results we were very happy with and wrote two solid publications on it.

You can control Dash robots with a cell phone

You can control Dash robots with a cell phone

CIRCUIT CELLAR: What led you and your co-founders to launch Dash Robotics in 2013? And can you tell us about your current team?

NICK: My co-founder Andrew and I were lab mates in grad school and climbing buddies. We both knew that we wanted to run our own business, because we couldn’t stand working in a cubicle; it’s why we were in grad school in the first place.

This idea of starting a business bounced around for a couple years but we never did anything with it. In the meantime, we had been to various events at schools and museums and saw that people loved the robot, they just went wild for it. Everyone asked to buy it but we always told them, “no, this is just a research tool.” In late 2012 we saw the first beginnings of all these smart toys and thought “well, what we have here is way cooler than that.” So we formed Dash Robotics, Inc. We hadn’t even graduated yet but we got a lot of support from the University and friends and family and were able to make it until February 2015 without taking any venture investment. Now I’m very happy we have that.

The robots are made flat. Simple fold and assemble them.

The robots are made flat. Simple fold and assemble them.

CIRCUIT CELLAR: Dash’s first robot is a phone-controlled, insect-like running robot. It is shipped “origami”-style for people to assemble themselves. Tell us a bit about the process of planning and designing the robot.

NICK: This is pretty tough to answer in one question. The “origami” style is a process called SCM that was originally developed at UC Berkeley. The design is all done in 2-D and then cut out and folded up to 3-D, so it takes a bit of experience to become good at designing mechanisms using this process. You can’t just build it in 3-D CAD and see what it will look like before making it.

There are some people who are trying to change that, like Dan Aukes from Harvard. Right now we still do it all on intuition and experience. The original robot was developed in 2009, and it saw incremental changes over the next 4 years or so. In 2013 when we founded the company we had a whole new set of requirements for the robot (a research tool and consumer product are vastly different) so we started making a lot of changes. There have probably been at least 50 revisions since 2013—maybe 100. Each time it gets a little better, and we do a lot of testing to make sure we’re on the right track.

CIRCUIT CELLAR: Is DIY, hobby robotics your main focus at Dash Robotics? Do plan you branch out, perhaps into robot systems for industry, military, or medical applications?

NICK: That’s our main focus right now, along with making a product that kids will love as well. I think there are a lot of potential directions like agriculture, infrastructure inspection, search and rescue, etc. That’s much further down the road though.

CIRCUIT CELLAR: What’s next for Dash Robotics? Where would you like to see the company in 12 months?

NICK: With its products flying off store shelves and a great team in place making it all happen!

CIRCUIT CELLAR: What are your thoughts on the future of robotics?

NICK: This is a great, and of course difficult, question. It also depends on how you define robotics. I think on one end you’re going to see a lot of jobs displaced by self-driving cars and trucks, robotic dishwashers, housecleaners, etc. On the other end AI is going to be able to do a lot of knowledge work now done by lawyers, doctors, and engineers. Both of those advances are going to be a major challenge for society.

If you’re talking about mobile robotics specifically, where a lot of my interest lies, there is a major challenge in actuators and power density. Boston Dynamics builds some amazing machines but the internal combustion engine is loud and dirty, and current lithium batteries are only going to get you so far. Tesla is working very hard on the battery problem, and hopefully its new Gigafactory will bring prices down. If Tesla makes a big advance in battery technology I think you may see a whole new category of mobile robots breaking out.

This interview appears in Circuit Cellar 304 (November 2015).


Rad-Tolerant megaAVR MCU for Space Applications

Atmel Corp. is now shipping the ATmegaS128 microcontroller targeting next-generation space applications. Atmel’s first Rad-Tolerant device, ATmegaS128 delivers full wafer lot traceability, a 64-lead  CQFP, space screening, space qualification according to QML and ESCC flow, and total ionizing dose up to 30 Krad (Si) for space applications.

The ATmegaS128 is available in a ceramic hermetic packaging and is pin-to-pin and drop-in compatible with existing ATmega128 MCUs. This provides flexibility between commercial and qualified devices and thus enables faster time-to-market and lower development costs.

Features and specs:

  • High-performance, low-power Atmel AVR 8-bit MCU
  • High endurance, non-volatile memory
  • Robust peripherals including 8- and 16-bit timers/counters, 6 PWM channels, 8-channel, 10-bit ADC, TWI/USARTs/SPI serial interface, programmable watchdog timer, on-chip analog compactor
  • Power-on reset and programmable brown-out detection
  • Internal calibrated RC oscillator
  • External and internal interrupt sources
  • Six sleep modes
  • Power-down, standby and extended standby

A complete STK600 starter kit and development system for the ATmegaS128 AVR MCU is available. You can design with an industrial version of the ATmega128—with the exact pin-out of the ATmegaS128—to save costs. The new AVRs are supported by the proven Atmel Studio IDP for developing and debugging Atmel SMART ARM processor-based MCUs and Atmel AVR MCU applications, along with the Atmel Software Framework.

Source: Atmel

New Software to Obtain Measurement Results without MIPI or Arbitrary Waveform Generator Expertise

Keysight Technologies recently announced introduced a software plug-in for the M8070A system software for M8000 Series BER test solutions. The M8085A MIPI C-PHY receiver test solution is designed for conformance and margin tests.Keysight-M8085

The MIPI C-PHY 1.0 standard supports camera and display applications. The standard comprises multilevel non-NRZ non-differential signaling. The Keysight M8190A arbitrary waveform generator (AWG) is the right instrument to generate such signals. The M8085A easy-to-use editor option enables you to set up the parameters and pattern content of test signals for turn-on and debug interactively from the GUI in familiar, application terms. During parameter adjustments, the software controls the AWG hardware to maintain uninterrupted signal generation.

In addition, the M8085A software provides the industry’s first complete and standard-conformant routines for calibration of signal parameters and physical layer (PHY) receiver tests. Thus, you can achieve results without expertise in the MIPI standard or with arbitrary waveform generators.

The software plug-in provides several options for selecting the error-detecting device. You can connect to the built-in detector in the device under test via the IBERReader interface, which transfers the test result to the M8085A software and displays the result in the GUI. Plus, it enables fully automated unattended tests.

The M8085A C-PHY software with various options is now available.

Source: Keysight 

New Power Supply Chip Attacks “Vampire Power”

STMicroelectronics recently announced a new power supply chip intended to minimize “vampire power.” Meeting the international specification for zero standby power, the new chip offers an intelligent way of of managing the wake-up function in appliances, industrial, and lighting equipment.

STmicro’s new VIPer0P IC helps reduce wasted power and CO2 emissions by enabling effective zero-power standby in appliances. With its patented smart-management capability, the VIPer0P enables an appliance to be woken up from standby via a touchscreen or remote control. In addition, the IC consumes less than 5 mW in idle mode (at 230-VAC supply).

An off-line power-converter IC, VIPer0P—which can be configured as a flyback, buck, or buck-boost switched-mode power supply (SMPS)—is the latest member of STMicro’s VIPerPlus series. Additional features include integrated high-voltage startup circuitry, error amplifier with 1.2-V reference and separate ground for direct feedback connection, and a sense-FET for energy-efficient current sensing. These simplify design and minimize external components thereby saving bill-of-materials costs and board space. In addition, VIPer0P’s self-supply design simplifies transformer selection by eliminating any need for an auxiliary winding.

Source: STMicroelectronics

New RS-232 Transceiver Family with Adjustable Low-Voltage Interface

Exar Corp. recently launched a new family of RS-232 (EIA/TIA-232) transceivers designed to operate from 3- to 5.5-V supplies. The XR32220, XR32430, and XR32431 transceivers include an adjustable low-voltage logic interface that simplifies their use in low- and multi-voltage systems.Exar EX051_XR32220

The XR32220 and XR32431 feature a low-voltage logic pin (VL) for adjusting the transceiver’s logic output levels and input thresholds for compatibility with lower supply voltage logic. The VL range is 1.65 to 5.5 V. The adjustable low-voltage interface eliminates the need for a level shifter/translator between the transceiver and UART or microcontroller.

Features and specs:

  • Wide 3- to 5-V supply operation
  • 1.65- to 5.5-V logic interface VL pin (XR32220, XR32431)
  • Auto on-line circuitry automatically wakes up from a 1-µA shutdown
  • Regulated charge pump yields stable RS-232 outputs regardless of VCC variations
  • XR32220: 250 kbps minimum transmission rate
  • XR32430, XR32431: 250 kbps/460 kbps/1 Mbps minimum transmission rate

The XR32220, XR32430, and XR32431 are available in RoHS-compliant, green/halogen free, space-saving 4 mm × 4 mm QFN (XR32220) and 5 mm × 5 mm QFN (XR32430/31) packages. They cost from $0.74 to $0.94 in 1,000-piece quantities. Demoboards and samples are available at http://www.exar.com/transceivers.


Source: Exar Corp.